CN114181205B - Pyrazolopyridine compound or salt thereof, and preparation method and application thereof - Google Patents

Abstract

The invention relates to pyrazolopyridine compounds or salts thereof and a preparation method and application thereof, in particular to a compound of a formula (I) or stereoisomers, tautomers, stable isotope derivatives, pharmaceutically acceptable salts or solvates thereof, wherein R ₁、R₂、R₃、R₄、R₅, a ring A, B, m and n are defined as in the specification, a preparation method thereof and a pharmaceutical composition containing the compounds, and application of the compounds in preparing medicines for treating or preventing RET-related diseases.

Description

Pyrazolopyridine compound or its salt and its preparation method and use

Technical Field

The present invention belongs to the field of chemical medicine technology, and specifically relates to a pyrazolopyridine compound with RET inhibitory activity, a preparation method thereof, and a pharmaceutical composition containing the compound, and also relates to the use of the pyrazolopyridine compound in the preparation of a drug for preventing or treating a disease related to RET.

Background Art

RET (REarranged during Transfection) protein is a receptor tyrosine kinase (RTK) and a transmembrane glycoprotein expressed by the proto-oncogene RET located on chromosome 10. It plays an important role in the development of the kidney and enteric nervous system in the embryonic stage. It is also critical in various tissues, such as neurons, neuroendocrine, hematopoietic tissues and male germ cells. Unlike other receptor tyrosine kinases, RET does not directly bind to ligand molecules: such as artemin, glial cell-derived neurotrophic factor (GDNF), and nerve growth factor (NGF), which all belong to the GNDF family of ligands (GFLs). These ligands usually bind to the GDNF family receptor α (GFRα), and the formed GFLs-GFRα complex mediates the self-dimerization of RET protein, causing trans-autophosphorylation of tyrosine on the intracellular domain, recruiting related adaptor proteins, and activating cascade reactions of signal transduction such as cell proliferation, thereby leading to excessive cell proliferation and the occurrence of cancer. Related signaling pathways include MAPK, PI3K, JAK-STAT, PKA, PKC, etc.

There are two main mechanisms of RET oncogenic activation: one is the new fusion protein produced by chromosomal rearrangement, usually a fusion of the RET kinase domain and a protein containing a self-dimerization domain; the other is that RET mutations directly or indirectly activate RET kinase activity. These changes at the somatic or germ cell level are involved in the pathogenesis of a variety of cancers. 10%-20% of patients with papillary thyroid cancer (PTC) have RET chromosomal rearrangements; 60% of patients with medullary thyroid carcinoma (MTC) have RET point mutations; and among all non-small cell lung cancer (NSCLC) patients, approximately 1-2% have RET fusion proteins, of which KIF5B is the most common.

Currently, multiple kinase inhibitors with RET inhibitory activity are mainly used to treat cancer patients with RET fusion. However, under this condition, due to off-target effects and drug toxicity, the drug dose is not enough to achieve a sufficient level of inhibition of RET expression. In addition, during the treatment of cancer, cancer cells will develop drug resistance through mutation. Once drug resistance occurs, the patient's treatment options will become very limited. Therefore, drugs that selectively inhibit abnormal RET expression, RET fusion and mutation are urgently needed.

Drugs currently on the market or under clinical development that are selectively designed for the RET target have shown good efficacy and safety in clinical trials of non-small cell lung cancer and thyroid cancer.

At present, there is still a great need to discover and develop new RET inhibitor compounds for the prevention and/or treatment of RET-related diseases. In addition to having satisfactory RET inhibitory activity, such compounds are also expected to have good or even improved drugability based on structural optimization, so as to provide more medication options for patients with related diseases while providing better therapeutic effects.

Brief description of the invention

The present invention relates to compounds that can be used to prevent or treat diseases associated with RET. In particular, it has been identified that the compounds of the present invention show satisfactory RET inhibitory activity and good performance in in vivo and/or in vitro pharmacokinetic experiments, indicating improved drugability and improved bioavailability. Therefore, the compounds of the present invention can not only achieve the purpose of preventing or treating diseases associated with RET, but also the prepared drugs are expected to have improved absorption, improved efficacy at the same dose, or provide the same efficacy at a lower dose and/or reduce possible side effects. Thus, the present invention also provides the use of the compounds of the present invention in the preparation of drugs for preventing or treating diseases associated with RET, pharmaceutical compositions comprising the compounds, and methods for preventing and/or treating diseases associated with RET by administering the compounds.

Therefore, in one aspect of the present invention, there is provided a compound of formula (I), a stereoisomer, a tautomer, a stable isotopic variant, a pharmaceutically acceptable salt or a solvate thereof:

in:

R ₁ is selected from hydrogen, halogen, cyano, nitro and C ₁ -C ₆ alkyl optionally substituted by halogen or cyano;

_R2 is selected from hydrogen, _C6 - _C10 aryl, 5-9 membered heteroaryl, _C3 - _C8 cycloalkyl, _C3 - _C8 cycloalkenyl, 3-8 membered heterocycloalkyl, 3-8 membered heterocycloalkenyl, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio, wherein the aryl, heteroaryl, cycloalkyl, cycloalkenyl, heterocycloalkyl, heterocycloalkenyl, alkyl, alkoxy and alkylthio are optionally substituted by 1, 2 or 3 groups independently selected from the following: halogen, cyano, nitro, hydroxy, _{C1 - C6} alkyl, C1- _C6 alkoxy and _C1 - _C6 alkylthio;

R ₃ is selected from hydrogen, halogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio;

_R4 is selected from hydrogen, _C6 - _C10 aryl, 5-9 membered heteroaryl, _C3 - _C8 cycloalkyl, _C3 - _C8 cycloalkenyl, 3-8 membered heterocycloalkyl, 3-8 membered heterocycloalkenyl, 3-8 membered heterocycloalkyloxy, 3-8 membered heterocycloalkenyloxy, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio, wherein the aryl, heteroaryl, cycloalkyl, cycloalkenyl, heterocycloalkyl, heterocycloalkenyl, alkyl, alkoxy and alkylthio are optionally substituted with 1, 2 or 3 groups independently selected from the following: halogen, cyano, nitro, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio;

R ₅ is selected from halogen, cyano, nitro, hydroxy, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio;

Ring A is selected from C ₆ -C ₁₀ arylene, 5-9 membered heteroarylene, C ₃ -C ₈ cycloalkylene, C ₃ -C ₈ cycloalkenylene, 3-8 membered heterocycloalkylene and 3-8 membered heterocycloalkenylene rings;

Ring B is selected from C ₆ -C ₁₀ aryl, 5-9 membered heteroaryl, C ₃ -C ₈ cycloalkyl, C ₃ -C ₈ cycloalkenyl, 3-8 membered heterocycloalkyl and 3-8 membered heterocycloalkenyl rings;

m is 0, 1, 2 or 3; and

n is 0, 1, 2 or 3.

In another aspect of the present invention, provided is a compound of formula (I), a stereoisomer, a tautomer, a stable isotopic variant, a pharmaceutically acceptable salt or a solvate thereof having RET inhibitory activity and being used as a medicament, especially as a RET inhibitor.

In another aspect of the present invention, there is provided a compound of formula (I), a stereoisomer, a tautomer, a stable isotopic variant, a pharmaceutically acceptable salt or a solvate thereof for use in treating or preventing, especially for treating a disease associated with RET.

In another aspect of the present invention, a pharmaceutical composition comprising a compound of the present invention and a pharmaceutically acceptable excipient is provided. In a specific aspect, the pharmaceutical composition of the present invention is provided for preventing or treating a disease associated with RET. In a specific aspect, the pharmaceutical composition may further comprise another therapeutically active ingredient suitable for use in combination with the compound of the present invention.

In another aspect of the present invention, there is provided a pharmaceutical combination (or pharmaceutical combination product) comprising a compound of the present invention and an additional active agent.

In another aspect of the present invention, a method for preventing or treating a disease associated with RET in an individual, such as a mammal, particularly a human, is provided, which method comprises administering an effective amount of the compound of the present invention described herein or a pharmaceutical composition comprising the same.

In another aspect of the present invention, there is provided use of the above-mentioned compound or pharmaceutical composition of the present invention for preventing or treating a disease associated with RET.

In another aspect of the present invention, provided is a use of the above-mentioned compound or pharmaceutical composition of the present invention in the preparation of a medicament for preventing or treating a disease associated with RET.

Preferably, the RET-related disease described in the present invention is selected from tumors or irritable bowel syndrome (IBS), and the tumor includes but is not limited to non-small cell lung cancer, small cell lung cancer, papillary thyroid cancer, medullary thyroid cancer, differentiated thyroid cancer, recurrent thyroid cancer, refractory differentiated thyroid cancer, multiple endocrine tumors 2A or 2B, pheochromocytoma, parathyroid hyperplasia, breast cancer, colorectal cancer, papillary renal cell carcinoma, gastrointestinal mucosal ganglioneuroma, pancreatic duct adenocarcinoma, multiple endocrine neoplasia, testicular cancer, chronic monocytic leukemia, salivary gland cancer, ovarian cancer, cervical cancer, etc.

In additional aspects, methods for synthesizing compounds of the invention are provided, with representative synthetic schemes and pathways being described below.

Other objects and advantages of the present invention will become apparent to those skilled in the art from a reading of the following detailed description.

For the above-mentioned compounds of the present invention for use as medicines, the methods of prevention or treatment of the present invention, the pharmaceutical compositions, the pharmaceutical combinations or the uses, the various preferred embodiments of the compounds of formula (I) defined herein are preferred, and the specific compounds listed herein are more preferred.

definition

Unless otherwise defined below, the meanings of all technical terms and scientific terms used herein are intended to be the same as those generally understood by those skilled in the art. Reference to the technology used herein is intended to refer to the technology generally understood in the art, including those changes in technology or replacement of equivalent technology that are obvious to those skilled in the art. Although it is believed that the following terms are well understood by those skilled in the art, the following definitions are still set forth to better explain the present invention.

The term "halo" or "halogen" as used herein means fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). Preferred halogens are fluorine or chlorine. The term "halogen-substituted" group as used herein is intended to include monohalogenated or polyhalogenated groups in which one or more (e.g., 2, 3, 4, 5 or 6) identical or different halogens replace one or more (e.g., 2, 3, 4, 5 or 6) hydrogens in the group.

As used herein, the term "cyano" refers to the group -CN.

As used herein, the term "nitro" refers to the group _-NO2 .

As used herein, the term "hydroxy" refers to -OH.

As used herein, the term "alkyl" refers to a straight or branched saturated hydrocarbon group consisting of carbon atoms and hydrogen atoms. Specifically, the alkyl group has 1-10, such as 1 to 6, 1 to 5, 1 to 4, 1 to 3 or 1 to 2 carbon atoms. For example, as used herein, the term "C ₁ -C ₆ alkyl" refers to a straight or branched saturated hydrocarbon group having 1 to 6 carbon atoms, examples of which are methyl, ethyl, propyl (including n-propyl and isopropyl), butyl (including n-butyl, isobutyl, sec-butyl or tert-butyl), pentyl (including n-pentyl, isopentyl, neopentyl), n-hexyl, 2-methylpentyl, etc. Specific alkyl groups have 1 to 3 carbon atoms.

The term "alkoxy" as used herein means the group -O-alkyl, wherein alkyl has the meaning described herein. Specifically, the term includes the group -OC _1-6 alkyl, more specifically -OC _1-3 alkyl. Representative examples of alkoxy include, but are not limited to, methoxy, ethoxy, propoxy (including n-propoxy, isopropoxy), butoxy (including n-butoxy, isobutoxy, tert-butoxy), pentoxy (including n-pentoxy, isopentyl, neopentyl), hexoxy (including n-hexyl, isohexyl) and the like. Specific alkoxy has 1 to 3 carbon atoms.

As used herein, the term "alkylthio" refers to -S-alkyl, wherein the alkyl is as defined above for "alkyl". Specifically, the term includes the group -SC _1-6 alkyl, more specifically -SC _1-3 alkyl. Representative examples of alkylthio include, but are not limited to, methylthio, ethylthio, propylthio (including n-propylthio, isopropylthio), butylthio (including n-butylthio, isobutylthio, tert-butylthio), pentylthio (including n-pentylthio, isopentylthio, neopentylthio), hexylthio (including n-hexylthio, isohexylthio) and the like. Specific alkylthio has 1 to 3 carbon atoms. As used herein, the term "halogen-substituted C ₁ -C ₆ alkyl" refers to the C ₁ -C ₆ alkyl described above, wherein one or more (e.g., 1, 2, 3, 4 or 5) hydrogen atoms are replaced by halogen. It will be appreciated by those skilled in the art that when the halogen substituent is more than one, the halogen may be the same or different, and may be located on the same or different C atoms. Examples of "halogen-substituted C ₁ -C ₆ alkyl" are -CH ₂ F, -CHF ₂ , -CF ₃ , -CCl ₃ , -C ₂ F ₅ , -C ₂ Cl ₅ , -CH ₂ CF ₃ , -CH ₂ Cl , -CH ₂ CH ₂ CF ₃ or -CF(CF ₃ ) ₂ and the like.

As used herein, the term "halogen-substituted C ₁ -C ₆ alkoxy" refers to the C ₁ -C ₆ alkoxy group as described above, wherein one or more (e.g., 1, 2, 3, 4, or 5) hydrogen atoms are replaced by halogen. It will be understood by those skilled in the art that when there are more than one halogen substituent, the halogens may be the same or different and may be located on the same or different C atoms. Examples of "halogen-substituted C ₁ -C ₆ alkoxy" include, for example, -OCH ₂ F, -OCHF ₂ , -OCF ₃ , -OCCl ₃ , -OC ₂ F ₅ , -OC ₂ Cl ₅ , -OCH ₂ CF ₃ , -OCH ₂ Cl, or -OCH ₂ CH ₂ CF ₃ , and the like.

As used herein, the term "cycloalkyl" refers to a monocyclic, fused polycyclic, bridged polycyclic or spirocyclic non-aromatic saturated monovalent hydrocarbon ring structure having a specified number of ring atoms. The cycloalkyl group may have 3 to 12 carbon atoms (i.e., _C3 - _C12 cycloalkyl), for example, 3 to 10, 3 to 8, 3 to 7, 3 to 6, 5 to 6 carbon atoms. Examples of suitable cycloalkyl groups include, but are not limited to, monocyclic structures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl; or polycyclic (e.g., bicyclic) structures, including spirocyclic, fused or bridged systems such as bicyclo[1.1.1]pentyl, bicyclo[2.2.1]heptyl, spiro[3.4]octanyl, bicyclo[3.1.1]hexyl, bicyclo[3.1.1]heptyl or bicyclo[3.2.1]octanyl, etc.).

As used herein, the term "cycloalkylene" refers to a cycloalkyl group as defined above, but it is a divalent group, the two valence bonds are not on the same ring atom. The cycloalkylene group may have 3 to 12 carbon atoms (i.e., _C3 - _C12 cycloalkylene), for example 3 to 10, 3 to 8, 3 to 7, 3 to 6, 5 to 6 carbon atoms. Examples of suitable cycloalkylene groups include, but are not limited to, monocyclic structures such as cyclopropylene, cyclobutylene, cyclopentylene (e.g., cyclopent-1,2-diyl, cyclopent-1,3-diyl), cyclohexylene (e.g., cyclohex-1,2-diyl, cyclohex-1,3-diyl, cyclohex-1,4-diyl), cycloheptylene, or cyclooctylene; or polycyclic (e.g., bicyclic) structures, including spiro, fused, or bridged systems, such as bicyclo[1.1.1]pentylene, bicyclo[2.2.1]heptylene, spiro[3.4]octylene, bicyclo[3.1.1]hexylene, bicyclo[3.1.1]heptylene, or bicyclo[3.2.1]octylene, etc.).

The term "cycloalkenyl" as used herein means a monocyclic, fused polycyclic, bridged polycyclic or spirocyclic non-aromatic unsaturated hydrocarbon ring structure having a specified number of ring atoms, comprising at least one (e.g., 1, 2, or 3) carbon-carbon double bonds. The cycloalkenyl group may have 3 to 12 carbon atoms (i.e., _C3 - _C12 cycloalkenyl), such as 3 to 10, 3 to 8, 3 to 7, 3 to 6, 5 to 6 carbon atoms. Examples of suitable cycloalkenyl groups include, but are not limited to, monocyclic structures such as cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, cyclohexadienyl, cycloheptenyl, cycloheptadienyl, cycloheptatrienyl or cyclooctenyl.

As used herein, the term "cycloalkenylene" refers to a cycloalkenyl group as defined above, but it is a divalent group, and the two valence bonds are not on the same ring atom. The cycloalkenylene group may have 3 to 12 carbon atoms (i.e., _C3 - _C12 cycloalkenylene), for example, 3 to 10, 3 to 8, 3 to 7, 3 to 6, 5 to 6 carbon atoms. Examples of suitable cycloalkenylene groups include, but are not limited to, monocyclic structures, such as cyclopropenylene, cyclobutenylene, cyclopentenylene, cyclopentadienylene, cyclohexenylene, cyclohexadienylene, cycloheptenylene, cycloheptadienylene, cycloheptatrienylene or cyclooctenylene.

The term "heterocycloalkyl" as used herein means a monocyclic, fused polycyclic, spirocyclic or bridged polycyclic non-aromatic saturated ring structure including one or more (e.g., 1, 2, 3 or 4) heteroatoms independently selected from O, N and S and the specified number of ring atoms, or its N-oxide, or its S-oxide or S-dioxide. The heterocycloalkyl group may have 3 to 12 ring members (which may be referred to as a 3-12 membered heterocycloalkyl group), for example, 3 to 10 ring members, 3 to 8 ring members, 3 to 7 ring members, 4 to 7 ring members, 5 to 6 ring members. The heterocycloalkyl group typically contains up to 4 (e.g., 1, 2, 3 or 4) heteroatoms. Examples of suitable heterocycloalkyl groups include, but are not limited to, azetidinyl, oxetanyl, thietanyl, pyrrolidinyl (e.g., 1-pyrrolidinyl, 2-pyrrolidinyl, and 3-pyrrolidinyl), tetrahydrofuranyl (e.g., 1-tetrahydrofuranyl, 2-tetrahydrofuranyl, and 3-tetrahydrofuranyl), tetrahydrothiophenyl (e.g., 1-tetrahydrothiophenyl, 2-tetrahydrothiophenyl, and 3-tetrahydrothiophenyl), piperidinyl (e.g., 1-piperidinyl), , 2-piperidinyl, 3-piperidinyl and 4-piperidinyl), tetrahydropyranyl (e.g. 4-tetrahydropyranyl), tetrahydrothiopyranyl (e.g. 4-tetrahydrothiopyranyl), morpholinyl (e.g. morpholino), thiomorpholinyl, dioxanyl, piperazinyl or azepanyl, diazepanyl such as 1,4-diazacycloheptyl, 3,6-diaza-bicyclo[3.1.1]heptyl or 3-aza-bicyclo[3.2.1]octyl.

As used herein, the term "heterocycloalkylene" means a heterocycloalkyl group as defined above, but it is a divalent group, and the two valence bonds are not on the same ring atom. Heterocycloalkylene may have 3 to 12 ring members (which may be referred to as 3-12 membered heterocycloalkylene), for example 3 to 10 ring members, 3 to 8 ring members, 3 to 7 ring members, 4 to 7 ring members, 5 to 6 ring members. Heterocycloalkylene typically contains up to 4 (e.g., 1, 2, 3 or 4) heteroatoms. Examples of suitable heterocycloalkylene groups include, but are not limited to, azetidinylene, oxatidinylene, thiacyclotidinylene, pyrrolidinylene (e.g., pyrrolidine-1,2-diyl, pyrrolidine-1,3-diyl, pyrrolidine-2,3-diyl), tetrahydrofuranylene (e.g., tetrahydrofuran-2,4-diyl, tetrahydrofuran-2,3-diyl, and tetrahydrofuran-2,5-diyl), piperidinylene (e.g., piperidine-1,2-diyl), , piperidine-1,3-diyl, piperidine-1,4-diyl, piperidine-2,4-diyl), tetrahydrothiophenylene, tetrahydropyranyl, tetrahydrothiopyranyl, morpholinylene, thiomorpholinylene, dioxanylene, piperazinylene or azacycloheptylene, diazacycloheptylene such as 1,4-diazacycloheptylene, 3,6-diaza-bicyclo[3.1.1]heptylene or 3-aza-bicyclo[3.2.1]octylene, preferably

The term "heterocycloalkenyl" as used herein means a "heterocycloalkyl" as defined herein that contains at least one (e.g., 1, 2, or 3) double bond. Examples of suitable heterocycloalkenyl groups include, but are not limited to:

wherein each W is selected from _CH2 , NH, O and S; each Y is selected from NH, O, C(=O), _SO2 and S; and each Z is selected from N and CH, provided that each ring contains at least one atom selected from N, O or S; for example, pyrrolinyl (e.g., 1-pyrrolinyl, 2-pyrrolidinyl, 3-pyrrolinyl, 4-pyrrolinyl or 5-pyrrolinyl), dihydrofuranyl (e.g., 1-dihydrofuranyl, 2-dihydrofuranyl, 3-dihydrofuranyl, 4-dihydrofuranyl or 5-dihydrofuranyl), dihydrothienyl (e.g., 1-dihydrothienyl, 2-dihydrothienyl, 3-dihydrothienyl or 4-dihydrothienyl), tetrahydropyridinyl (e.g., 1-, 2-, 3-, 4-, 5- or 6-tetrahydropyridinyl), tetrahydropyranyl (e.g., 4-tetrahydropyranyl) or tetrahydrothiopyranyl (e.g., 4-tetrahydrothiopyranyl).

The term "heterocycloalkenylene" as used herein means a heterocycloalkenyl group as defined above, but it is a divalent group, the two valence bonds are not on the same ring atom. Suitable examples of heterocycloalkenylene include, but are not limited to:

wherein each W is selected from CH ₂ , NH, O and S; each Y is selected from NH, O, C(═O), SO ₂ and S; and each Z is selected from N and CH, provided that each ring contains at least one atom selected from N, O or S; for example, pyrrolinylene, dihydrofuranylene, dihydrothienylene, tetrahydropyridylene, tetrahydropyranylene or tetrahydrothiopyranylene, preferably More preferred

The term "aryl" as used herein means a monovalent aromatic hydrocarbon radical derived by removing one hydrogen atom from a single carbon atom in an aromatic ring system. Specifically, aryl refers to a monocyclic or fused polycyclic aromatic ring structure having the specified number of ring atoms. Specifically, the term includes groups containing 6 to 14, e.g., 6 to 10, preferably 6 ring members. Specific aryl groups include phenyl and naphthyl, the most specific aryl being phenyl.

The term "arylene" as used herein means an aryl group as defined above, but which is a divalent group, the two valences not being on the same ring atom. Specific arylene groups include phenylene, such as benzene-1,2-diyl, benzene-1,3-diyl or benzene-1,4-diyl.

As used herein, the term "heteroaryl" means a monocyclic or fused polycyclic aromatic ring structure comprising one or more (e.g., 1, 2, 3, or 4) heteroatoms independently selected from O, N, and S and the specified number of ring atoms, or an N-oxide thereof, or an S-oxide or S-dioxide thereof. Specifically, the aromatic ring structure may have 5 to 9 ring members. The heteroaryl group may be, for example, a 5-6-membered monocyclic ring, or a fused bicyclic structure formed by fused two 5-membered rings or fused 5-membered and 4-membered rings. The heteroaryl ring will typically contain up to 4 heteroatoms, more typically up to 3 heteroatoms, more typically up to 2, for example a single heteroatom independently selected from O, N, and S, wherein N and S may be in an oxidation state such as N-oxide, S=O, or S(O) _2. In one embodiment, the heteroaryl ring contains at least one ring nitrogen atom, at least one ring sulfur atom, or at least one ring oxygen atom. For example, the heteroaryl group can be a 5-6 membered heteroaryl group containing 1 or 2 heteroatoms independently selected from N, O or S. Examples of suitable 5-membered monocyclic heteroaryl groups include, but are not limited to, pyrrolyl, furanyl, thienyl, imidazolyl, furazanyl, oxazolyl, oxadiazolyl, oxatriazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, triazolyl and tetrazolyl; examples of suitable 6-membered monocyclic heteroaryl groups include, but are not limited to, pyridinyl, pyrazinyl, pyridazinyl, pyrimidinyl and triazinyl.

The term "heteroarylene" as used herein means a heteroaryl group as defined above, but it is a divalent group, the two valence bonds not being on the same ring atom. The heteroarylene group may be a 5-6 membered heteroarylene group containing 1 or 2 heteroatoms independently selected from N, O or S. Examples of suitable 5-membered monocyclic heteroarylene groups include, but are not limited to, pyrrolylene, furanylene, thienylene, imidazolylene, furazanylene, oxazolylene, oxadiazolylene, oxatriazolylene, isoxazolylene, thiazolylene, isothiazolylene, pyrazolylene, triazolylene and tetrazolylene; examples of suitable 6-membered monocyclic heteroaryl groups include, but are not limited to, pyridinylene, pyrazinylene, pyridazinylene, pyrimidinylene and triazinylene; preferably

Substituents are described as "optionally substituted" meaning that the group can be unsubstituted or substituted with one or more (e.g., 0, 1, 2, 3, 4, or 5 or more, or any range derivable therein) of the substituents listed for the group, wherein the substituents can be the same or different. In one embodiment, the optionally substituted group is substituted with 1 substituent. In another embodiment, the optionally substituted group is substituted with 2 substituents. In another embodiment, the optionally substituted group is substituted with 3 substituents. In another embodiment, the optionally substituted group is substituted with 4 substituents.

Those skilled in the art of organic synthesis will appreciate that a stable chemically feasible heterocyclic ring, whether aromatic or non-aromatic, wherein the maximum number of heteroatoms or the type of heteroatoms contained is determined by the ring size, the degree of unsaturation, and the valence of the heteroatoms. In general, a heterocyclic ring may have 1 to 4 heteroatoms, provided that the heterocyclic ring or heteroaromatic ring is chemically feasible and stable.

The term "compound of the present invention" as used herein is intended to cover compounds of the general formula (I) as defined herein or any preferred or specific embodiment thereof (including compounds of formula (Ia) and formula (Ib)), their stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts or solvates, and prodrugs. Similarly, the term "intermediate" herein, whether or not it is claimed itself, is intended to cover its free form and the above-mentioned derivative forms if the context permits.

The term "pharmaceutically acceptable" as used herein refers to molecular entities and compositions that are or are approvable by relevant agencies in various countries, or are listed in the generally recognized pharmacopoeia for use in animals, and more particularly in humans, or that do not produce adverse, allergic or other untoward reactions when administered in appropriate amounts to animals, such as humans.

The term "pharmaceutically acceptable salt" as used herein means a salt of the compound of the present invention that is pharmaceutically acceptable and has the desired pharmacological activity of the parent compound. Specifically, such salts are non-toxic and may be inorganic acid addition salts or organic acid addition salts and base addition salts. Specifically, such salts include: (1) acid addition salts formed with inorganic acids, such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, etc.; or acid addition salts formed with organic acids, such as acetic acid, propionic acid, hexanoic acid, glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid, malic acid, maleic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, 2-naphthalenesulfonic acid, 4-toluenesulfonic acid. or (2) salts formed when an acidic proton present in the parent compound is replaced by a metal ion such as an alkali metal ion, an alkaline earth metal ion or an aluminum ion, or coordinated with an organic base such as ethanolamine, diethanolamine, triethanolamine, N-methylglucamine, etc. Those skilled in the art will be aware of the general principles and techniques for preparing pharmaceutically acceptable salts, such as those described in Berge et al., Pharm ScL, 66, 1-19. (1977).

The term "prodrug" as used herein means a compound having a cleavable group and becoming a pharmaceutically active compound of the present invention in vivo by solvolysis or under physiological conditions, including derivatives of the compounds of the present invention. Prodrugs include acid derivatives well known in the art, such as esters prepared by reacting the parent acid with a suitable alcohol, or amides prepared by reacting the parent acid compound with a substituted or unsubstituted amine, or anhydrides or mixed anhydrides. Simple aliphatic or aromatic esters, amides and anhydrides derived from the acid groups pendant to the compounds of the present invention are particularly suitable prodrugs. Specific such prodrugs are C _1-8 alkyl, C _2-8 alkenyl, optionally substituted C _6-10 aryl and (C _6-10 aryl)-(C _1-4 alkyl) esters of the compounds of the present invention.

The present invention also includes all pharmaceutically acceptable isotopic compounds, which are identical to the compounds of the present invention except that one or more atoms are replaced by atoms having the same atomic number but an atomic mass or mass number different from the atomic mass or mass number predominant in nature. Examples of isotopes suitable for inclusion in the compounds of the present invention include, but are not limited to, isotopes of hydrogen (e.g., 2H, 3H); isotopes of carbon (e.g., 11C, 13C, and 14C); isotopes of chlorine (e.g., 36Cl); isotopes of fluorine (e.g., 18F); isotopes of iodine (e.g., 123I and 125I); isotopes of nitrogen (e.g., 13N and 15N); isotopes of oxygen (e.g., 15O, 17O, and 18O); isotopes of phosphorus (e.g., 32P); and isotopes of sulfur (e.g., 35S).

As used herein, the term "stereoisomer" means an isomer formed due to at least one asymmetric center. In compounds with one or more (e.g., 1, 2, 3, or 4) asymmetric centers, it can produce a racemic mixture, a single enantiomer, a diastereomeric mixture, and a single diastereomer. Specific individual molecules can also exist as geometric isomers (cis/trans). Similarly, the compounds of the present invention can exist as mixtures (commonly referred to as tautomers) of two or more different structural forms in rapid equilibrium. Representative examples of tautomers include keto-enol tautomers, phenol-ketone tautomers, nitroso-oxime tautomers, imine-enamine tautomers, etc. For example, nitroso-oxime can exist in the following tautomeric form equilibrium in solution:

It should be understood that the scope of the present application covers all such isomers or mixtures thereof in any proportion (e.g., 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%).

Unless otherwise indicated, the compounds of the present invention are intended to exist in the form of stereoisomers, including cis and trans isomers, optical isomers (e.g., R and S enantiomers), diastereomers, geometric isomers, rotational isomers, conformational isomers, atropisomers, and mixtures thereof. The compounds of the present invention may exhibit more than one type of isomerism and consist of mixtures thereof, such as racemic mixtures and diastereomeric pairs.

The term "solvate" as used herein refers to a solvent addition form containing a stoichiometric or non-stoichiometric amount of a solvent, including, for example, a solvate with water, such as a hydrate, or a solvate with an organic solvent, such as methanol, ethanol or acetonitrile, i.e., as a methanolate, ethanolate or acetonitrile, respectively; or in the form of any polymorph. It should be understood that such solvates of the compounds of the invention also include solvates of pharmaceutically acceptable salts of the compounds of the invention.

As used herein, the term "prevention" means administering one or more compounds of the invention to an individual, such as a mammal, such as a human, suspected of suffering from or susceptible to a RET-related disease as defined herein, especially an inflammatory or autoimmune disease, such that the risk of suffering from the defined disease is reduced. The term "prevention" encompasses the use of the compounds of the invention before the diagnosis or determination of any clinical and/or pathological symptoms.

The term "treatment" as used herein refers to administering one or more compounds of the present invention as described herein to a subject, such as a mammal, such as a human, who suffers from the disease or has symptoms of the disease, to cure, alleviate, reduce or affect the disease or the symptoms of the disease. In a specific embodiment of the present invention, the disease is a RET-related disease as defined herein, especially an inflammatory or autoimmune disease.

The term "RET-related disease" as used herein means that RET promotes the occurrence and development of the disease, or inhibiting RET will reduce the incidence of the disease, reduce or eliminate the disease symptoms. For the present invention, "RET-related disease" is selected from tumors or irritable bowel syndrome (IBS), and tumors include but are not limited to non-small cell lung cancer, small cell lung cancer, papillary thyroid cancer, medullary thyroid cancer, differentiated thyroid cancer, recurrent thyroid cancer, refractory differentiated thyroid cancer, multiple endocrine tumors 2A or 2B, pheochromocytoma, parathyroid hyperplasia, breast cancer, colorectal cancer, papillary renal cell carcinoma, gastrointestinal mucosal ganglioneuroma, pancreatic duct adenocarcinoma, multiple endocrine neoplasia, testicular cancer, chronic monocytic leukemia, salivary gland cancer, ovarian cancer, cervical cancer, etc.

As used herein, the term "cancer" or "tumor" refers to neoplastic cell growth and proliferation, whether malignant or benign, and all precancerous and cancerous cells and tissues. For the compounds, methods, pharmaceutical compositions, drug combinations and uses of the present invention, the cancer or tumor includes, but is not limited to, colon cancer, pancreatic cancer, breast cancer, ovarian cancer, prostate cancer, squamous cell carcinoma, basal cell carcinoma, adenocarcinoma, sweat gland carcinoma, sebaceous gland carcinoma, lung cancer, leukemia, bladder cancer, gastric cancer, cervical cancer, testicular cancer, skin cancer, rectal cancer, thyroid cancer, kidney cancer, uterine cancer, pemphigus cancer, liver cancer, acoustic neuroma, oligodendroglioma, meningioma, neuroblastoma, eye cancer.

The term "therapeutically effective amount" as used herein means an amount that, when administered to an individual for the treatment of a disease, is sufficient to reduce or completely alleviate the symptoms or other adverse effects of the disease; reverse, completely stop or slow the progression of the disease; or reduce the risk of worsening of the disease. The "effective amount" varies depending on the compound, the disease and its severity, and the age, weight, etc. of the individual to be treated.

As used herein, the term "individual" includes humans or non-human animals. Exemplary human individuals include human individuals (referred to as patients) suffering from diseases (e.g., diseases described herein) or normal individuals. In the present invention, "non-human animals" include all vertebrates, such as non-mammals (e.g., birds, amphibians, reptiles) and mammals, such as non-human primates, livestock and/or domesticated animals (e.g., sheep, dogs, cats, cows, pigs, etc.).

The "pharmaceutical composition" described in the present invention refers to a composition comprising one or more compounds of formula (I) or their stereoisomers, tautomers, stable isotope derivatives, pharmaceutically acceptable salts or solvates and a carrier generally accepted in the art for delivering biologically active compounds to an organism (e.g., human).

The term "drug combination" as used herein means that the compounds of the present invention can be combined with other active agents to achieve the purpose of the present invention. The other active agents may be one or more additional compounds of the present invention, or may be a second or additional (e.g., a third) compound that is compatible with the compounds of the present invention, i.e., does not adversely affect each other, or has complementary activities. Such active agents are suitably combined in an effective amount to achieve the intended purpose. The other active agents may be co-administered with the compounds of the present invention in a single pharmaceutical composition, or may be administered separately from the compounds of the present invention in different discrete units, and when administered separately, may be performed simultaneously or sequentially. The sequential administration may be close or distant in time.

The term "pharmaceutically acceptable excipient or carrier" as used herein refers to one or more compatible solid or liquid fillers or gel substances, which are pharmacologically inactive, compatible with the other ingredients in the composition, and should be acceptable for administration to warm-blooded animals such as humans, and are used as carriers or media for the compounds of the present invention in the administration form. Examples include, but are not limited to, cellulose and its derivatives (such as sodium carboxymethyl cellulose, cellulose acetate, etc.), gelatin, talc, solid lubricants (such as magnesium stearate), calcium sulfate, vegetable oils, polyols (such as propylene glycol, glycerol, mannitol, sorbitol, etc.), emulsifiers (such as Tweens), wetting agents (such as sodium lauryl sulfate), colorants, flavorings, stabilizers, antioxidants, preservatives, etc.

It should be understood that the dosages referred to herein when describing the compounds of the present invention, pharmaceutical compositions, pharmaceutical combinations containing the same, and related uses and methods are based on the weight of the free form, and not on any salts, hydrates or solvates thereof, etc., unless otherwise defined in the specification.

Compounds of the present invention

The terms "invented compounds" and "compounds of the present invention" and the like used throughout this application, unless otherwise indicated, encompass compounds of formula (I) as defined in the various embodiments herein and in specific or preferred embodiments thereof, their stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts or solvates, and prodrugs. The stereoisomers, tautomers, stable isotopic variants, pharmaceutically acceptable salts or solvates, and prodrugs are as described in the definition section above. Preferably, the compound of the present invention is a free form of a compound of formula (I) or a pharmaceutically acceptable salt or solvate thereof; most preferably, it is a free form of a compound of formula (I) or a pharmaceutically acceptable salt thereof.

Certain compounds of the present invention may exist in multiple crystalline or amorphous forms, which also fall within the scope of the present invention. When in solid crystalline form, compounds of formula (I) may be in the form of co-crystals with another chemical entity, and the present specification includes all such co-crystals.

In the presence of chiral centers, the compounds of the present invention may exist as individual enantiomers or mixtures of enantiomers. According to one embodiment, there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof, which is a single enantiomer with an enantiomeric excess (%ee) >95, >98% or >99%. Preferably, a single enantiomer is present with an enantiomeric excess (%ee) of >99%.

Specifically, in one aspect, the present invention provides a compound of formula (I), a stereoisomer, a tautomer, a stable isotopic variant, a pharmaceutically acceptable salt or a solvate thereof:

in:

R ₁ is selected from hydrogen, halogen, cyano, nitro and C ₁ -C ₆ alkyl optionally substituted by halogen or cyano;

_R2 is selected from hydrogen, _C6 - _C10 aryl, 5-9 membered heteroaryl, _C3 - _C8 cycloalkyl, _C3 - _C8 cycloalkenyl, 3-8 membered heterocycloalkyl, 3-8 membered heterocycloalkenyl, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio, wherein the aryl, heteroaryl, cycloalkyl, cycloalkenyl, heterocycloalkyl, heterocycloalkenyl, alkyl, alkoxy and alkylthio are optionally substituted by 1, 2 or 3 groups independently selected from the following: halogen, cyano, nitro, hydroxy, _{C1 - C6} alkyl, C1- _C6 alkoxy and _C1 - _C6 alkylthio;

R ₃ is selected from hydrogen, halogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio;

_R4 is selected from hydrogen, _C6 - _C10 aryl, 5-9 membered heteroaryl, _C3 - _C8 cycloalkyl, _C3 - _C8 cycloalkenyl, 3-8 membered heterocycloalkyl, 3-8 membered heterocycloalkenyl, 3-8 membered heterocycloalkyloxy, 3-8 membered heterocycloalkenyloxy, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio, wherein the aryl, heteroaryl, cycloalkyl, cycloalkenyl, heterocycloalkyl, heterocycloalkenyl, alkyl, alkoxy and alkylthio are optionally substituted with 1, 2 or 3 groups independently selected from halogen, cyano, nitro, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio;

R ₅ is selected from halogen, cyano, nitro, hydroxy, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio;

Ring A is selected from C ₆ -C ₁₀ arylene, 5-9 membered heteroarylene, C ₃ -C ₈ cycloalkylene, C ₃ -C ₈ cycloalkenylene, 3-8 membered heterocycloalkylene and 3-8 membered heterocycloalkenylene rings;

Ring B is selected from C ₆ -C ₁₀ aryl, 5-9 membered heteroaryl, C ₃ -C ₈ cycloalkyl, C ₃ -C ₈ cycloalkenyl, 3-8 membered heterocycloalkyl and 3-8 membered heterocycloalkenyl rings;

m is 0, 1, 2 or 3; and

n is 0, 1, 2 or 3.

In one embodiment of the compounds of formula (I), R ₁ is halogen, cyano or nitro.

In one embodiment of the compounds of formula (I), R ₁ is cyano.

In one embodiment of the compounds of formula (I), _R2 is selected from 5-6 membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S (specific examples include pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyridazinyl or pyrimidinyl), _C1 - _C6 alkyl, _C1 - _C6 alkoxy and C1- _C6 alkylthio, which are optionally substituted by 1, 2 or 3 groups independently selected from: halogen, hydroxyl and _{C1 - C6} alkyl;

In one embodiment of the compound of formula (I), R ₂ is selected from 5-membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S (specific examples include pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl or pyrazolyl), C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio, which is optionally substituted by 1 group independently selected from the following: hydroxyl and C ₁ -C ₆ alkyl;

In one embodiment of the compound of formula (I), R ₂ is selected from 5-membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S, optionally substituted by C ₁ -C ₆ alkyl (specific examples include pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl or pyrazolyl) and C ₁ -C ₆ alkoxy optionally substituted by hydroxy;

In one embodiment of the compound of formula (I), R ₂ is methyl substituted pyrazolyl or hydroxy substituted C ₁ -C ₆ alkoxy;

In one embodiment of the compounds of formula (I), R ₂ is

In one embodiment of the compounds of formula (I), R ₃ is selected from hydrogen and C ₁ -C ₆ alkyl.

In one embodiment of the compounds of formula (I), R ₃ is selected from hydrogen and C ₁ -C ₃ alkyl.

In one embodiment of the compounds of formula (I), R ₃ is hydrogen or methyl.

In one embodiment of the compounds of formula (I), R ₃ is hydrogen.

In one embodiment of the compounds of formula (I), the carbon to which _R3 is attached is in the S or R configuration.

In one embodiment of the compound of formula (I), _R4 is selected from phenyl, 5-6 membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S, 5-6 membered heterocycloalkyl, 5-6 membered heterocycloalkenyl, 5-6 membered heterocycloalkyloxy, 5-6 membered heterocycloalkenyloxy, _C1 - _C6 alkyl, _C1 - _C6 alkoxy and _C1 - _C6 alkylthio, which are optionally substituted by 1, 2 or 3 groups independently selected from halogen, hydroxy and _C1 - _C6 alkyl;

Preferably, the 5-6 membered heteroaryl is selected from pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, pyridinyl, pyrazinyl, pyridazinyl and pyrimidinyl;

The 5-6 heterocycloalkyl group is selected from pyrrolidinyl, tetrahydrofuranyl, tetrahydrothiophenyl, piperidinyl, tetrahydropyranyl, tetrahydrothiopyranyl), morpholinyl, thiomorpholinyl, dioxanyl or piperazinyl;

The 5-6 membered heterocycloalkenyl group is selected from pyrrolinyl, dihydrofuranyl, dihydrothiophenyl, tetrahydropyridinyl, tetrahydropyranyl and tetrahydrothiopyranyl.

In one embodiment of the compounds of formula (I), _R is selected from 5-membered heteroaryl (specific examples include pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl or pyrazolyl) containing 1, 2 or 3 heteroatoms independently selected from N, O or S, 5-6-membered heterocycloalkyl, 5-6-membered heterocycloalkyloxy, C ₁ -C ₆ alkyl and C ₁ -C ₆ alkoxy, which are optionally substituted by 1, 2 or 3 groups independently selected from halogen and C ₁ -C ₆ alkyl.

In one embodiment of the compounds of formula (I), R ₄ is selected from pyrazolyl, pyrrolidinyl, tetrahydropyranyloxy, morpholinyl, tetrahydrofuranyloxy, C ₁ -C ₆ alkyl and C ₁ -C ₆ alkoxy, which are optionally substituted with halogen.

In one embodiment of the compounds of formula (I), R ₄ is Pyrrolidin-1-yl, methoxy, ethoxy, isopropoxy, trifluoromethoxy or CF ₃ .

In one embodiment of the compounds of formula (I), R ₅ is selected from halogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio;

In one embodiment of the compounds of formula (I), R ₅ is selected from C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy and C ₁ -C ₆ alkylthio.

In one embodiment of the compounds of formula (I), R ₅ is selected from C ₁ -C ₃ alkyl;

In one embodiment of the compound of formula (I), R ₅ is selected from methyl, ethyl and propyl, preferably methyl;

In one embodiment of the compounds of formula (I), m is 0 or 1.

In one embodiment of the compounds of formula (I), n is 0 or 1.

In one embodiment of the compounds of formula (I), m is 1.

In one embodiment of the compounds of formula (I), n is 0.

In one embodiment of the compound of formula (I), Ring A is selected from phenylene, 5-9 membered heteroarylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, C ₃ -C ₈ cycloalkylene, C ₃ -C ₈ cycloalkenylene, 3-8 membered heterocycloalkylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, and 3-8 membered heterocycloalkenylene ring containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compound of formula (I), Ring A is selected from phenylene, 5-6 membered heteroarylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, C ₃ -C ₈ cycloalkylene, C ₃ -C ₈ cycloalkenylene, 3-8 membered heterocycloalkylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, and 3-8 membered heterocycloalkenylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compound of formula (I), Ring A is selected from phenylene, 5-membered heteroarylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, C ₃ -C ₆ cycloalkylene, C ₃ -C ₆ cycloalkenylene, 3-6-membered heterocycloalkylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S, and 3-6-membered heterocycloalkenylene containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compound of formula (I), ring A is selected from phenylene, pyrrolylene, furanylene, thienylene, imidazolylene, furazanylene, oxazolylene, oxadiazolylene, oxatriazolylene, isoxazolylene, thiazolylene, isothiazolylene, pyrazolylene, thiadiazolylene, triazolylene, tetrazolylene, pyridinylene, pyrazinylene, pyridazinylene, pyrimidinylene, triazinylene, azetidinylene, pyrrolidinylene, pyrrolinylene, cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene, piperazinylene, piperidinylene, tetrahydropyridinylene, 3,6-diaza-bicyclo[3.1.1]heptylene, 3-aza-bicyclo[3.2.1]octylene and 1,4-diazacycloheptylene.

In one embodiment of the compound of formula (I), Ring A is selected from pyrazolylene, thiadiazolylene, pyrrolidinylene, pyrrolinylene, cyclohexylene, piperazinylene, piperidinylene, tetrahydropyridinylene, 3,6-diaza-bicyclo[3.1.1]heptylene, 3-aza-bicyclo[3.2.1]octylene and 1,4-diazacycloheptylene.

In one embodiment of the compound of formula (I), Ring A is selected from

In one embodiment of the compound of formula (I), Ring B is selected from phenyl, 5-9 membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S, C ₃ -C ₈ cycloalkyl, C ₃ -C ₈ cycloalkenyl, 3-8 membered heterocycloalkyl containing 1, 2 or 3 heteroatoms independently selected from N, O or S, and 3-8 membered heterocycloalkenyl ring containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compounds of formula (I), Ring B is selected from phenyl and 5-6 membered heteroaryl containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compounds of formula (I), Ring B is selected from phenyl, a 6-membered heteroaryl group containing 1, 2 or 3 heteroatoms independently selected from N, O or S;

In one embodiment of the compounds of formula (I), Ring B is selected from phenyl, pyrrolyl, furanyl, thienyl, imidazolyl, furazanyl, oxazolyl, oxadiazolyl, oxatriazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyridinyl, pyrazinyl, pyridazinyl, pyrimidinyl and triazinyl rings.

In one embodiment of the compounds of Formula (I), Ring B is a pyridinyl ring.

In one embodiment of the compounds of formula (I), the group Selected from

It should be noted that the compounds of formula (I) of the present invention encompass the above independent embodiments or specific embodiments, and also encompass embodiments consisting of any combination or sub-combination of the above embodiments or specific embodiments, and also encompass embodiments consisting of any combination of any preferred or exemplified embodiments.

It should be understood that the combination and/or substitution of groups in the general formula compounds should be based on the premise of complying with the valence rules.

Preferably, the compound of formula (I) of the present invention has the structure of formula (Ia),

wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , m, n and A each have the meanings defined above for the compounds of formula (I) in general or in specific embodiments.

More preferably, the compound of formula (I) of the present invention has the structure of formula (Ib),

wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , n and A each have the meanings defined above for the compounds of formula (I) in general or in specific embodiments.

More preferably, the compound of formula (I) of the present invention has the structure of formula (Ic),

wherein R ₂ , R ₃ , R ₄ , R ₅ , n and A each have the meanings defined above for the compounds of formula (I) in general or in specific embodiments.

Most preferably, the compound of formula (I) of the present invention is selected from the following specific compound examples:

Advantageous Effects of the Invention

The present invention provides a class of pyrazolopyridine compounds having the structural characteristics of general formula (I). Studies have shown that the compounds can effectively inhibit RET kinase, RET fusion and mutation activity, and can be used as therapeutic drugs for diseases related to abnormal RET expression.

The compounds of the present invention have the following beneficial effects:

High RET kinase inhibitory activity; IC50 in the RET kinase inhibition assay is in the range of 0.1 nM to 1 μM, preferably in the range of 0.1 nM to 0.1 μM; and/or

High RET fusion and mutation activity; and/or

Having good pharmacokinetic properties, such as having a longer t _1/2 , so that, for example, the dosing interval can be increased, a longer half-life, and better patient compliance; and/or

Having improved AUC0-t data, better drugability, and higher bioavailability, as demonstrated in the following active example 6; and/or

Good safety, such as membrane permeability, P450 (reduced risk of drug interactions), solubility and other excellent properties.

Based on the beneficial effects of the above compounds of the present invention, the present invention also provides the following technical solutions in various aspects.

Compounds of the invention for use in therapy or as a medicament

In one aspect, the present invention provides compounds of the present invention for use as medicaments, in particular as RET inhibitors.

In another aspect, the present invention provides compounds of the present invention for use in therapy, in particular for use in the treatment and/or prevention of diseases associated with RET.

In a specific embodiment, the present invention provides compounds of the present invention for treating and/or preventing diseases in which RET promotes the occurrence and development of the disease or in which inhibition of RET will reduce the incidence of the disease, reduce or eliminate the symptoms of the disease, such as tumors or irritable bowel syndrome (IBS), tumors including but not limited to non-small cell lung cancer, small cell lung cancer, papillary thyroid cancer, medullary thyroid cancer, differentiated thyroid cancer, recurrent thyroid cancer, refractory differentiated thyroid cancer, multiple endocrine tumors 2A or 2B, pheochromocytoma, parathyroid hyperplasia, breast cancer, colorectal cancer, papillary renal cell carcinoma, gastrointestinal mucosal ganglioneuroma, pancreatic duct adenocarcinoma, multiple endocrine neoplasia, testicular cancer, chronic monocytic leukemia, salivary gland cancer, ovarian cancer, cervical cancer, etc.

Pharmaceutical compositions and their administration

On the other hand, in order to use the compounds of this specification for treatment or prevention purposes, the compounds of the present invention can be formulated into pharmaceutical compositions according to standard pharmaceutical practices. At the same time, based on the good pharmacokinetic properties, improved AUC0-last, and good drugability of the compounds of the present invention, drugs with better pharmacokinetic properties and higher bioavailability can be prepared from the compounds of the present invention.

Therefore, the present invention provides a pharmaceutical composition comprising the above-mentioned compound of the present invention and a pharmaceutically acceptable excipient.

In a specific embodiment, the pharmaceutical composition of the present invention is provided for preventing or treating a disease associated with RET in, for example, a mammal such as a human individual.

In a specific embodiment, the pharmaceutical composition of the present invention may further comprise additional therapeutically active ingredients suitable for use in combination with the compounds of the present invention.

The pharmaceutical composition of the present invention can be formulated by techniques known to those skilled in the art, such as those disclosed in Remington's Pharmaceutical Sciences 20th edition. For example, the pharmaceutical composition of the present invention described above can be prepared by mixing the compound of the present invention with one or more pharmaceutically acceptable excipients. The preparation may further include the step of mixing one or more other active ingredients with the compound of the present invention and one or more pharmaceutically acceptable excipients.

The excipients selected for inclusion in a particular composition will depend on a variety of factors, such as the mode of administration and the form of the composition provided. Suitable pharmaceutically acceptable excipients are well known to those skilled in the art and are described in, for example, Ansel, Howard C., et al., Ansel's Pharmaceutical Dosage Forms and Drug Delivery Systems. Philadelphia: Lippincott, Williams & Wilkins, 2004, including, for example, adjuvants, diluents (e.g., glucose, lactose or mannitol), carriers, pH adjusters, buffers, sweeteners, fillers, stabilizers, surfactants, wetting agents, lubricants, emulsifiers, suspending agents, preservatives, antioxidants, opacifiers, glidants, processing aids, colorants, flavoring agents, flavoring agents, other known additives.

The pharmaceutical composition of the present invention can be applied in a standard manner. For example, suitable modes of application include oral, intravenous, rectal, parenteral, topical, transdermal, ophthalmic, nasal, cheek or pulmonary (inhalation) administration, wherein parenteral infusion includes intramuscular, intravenous, intraarterial, intraperitoneal or subcutaneous administration. For these purposes, the compounds of the present invention can be formulated into, for example, tablets, capsules, syrups, powders, granules, aqueous or oily solutions or suspensions, (lipid) emulsions, dispersible powders, suppositories, ointments, creams, drops, aerosols, dry powder preparations and sterile injectable aqueous or oily solutions or suspensions by methods known in the art.

The size of the preventive or therapeutic dose of the compounds of the present invention will vary according to a series of factors, including the individual treated, the severity of the disease or condition, the rate of administration, the disposal of the compound and the judgment of the prescribing physician. In general, the effective dose is about 0.0001 to about 5000 mg per kg body weight per day, for example, about 0.01 to about 1000 mg/kg/day (single or divided administration). For a 70kg person, this will add up to about 0.007 mg/day to about 7000 mg/day, for example, about 0.7 mg/day to about 1500 mg/day. According to the mode of administration, the content or dosage of the compound of the present invention in the pharmaceutical composition can be about 0.01 mg to about 1000 mg, suitably 0.1-500 mg, preferably 0.5-300 mg, more preferably 1-150 mg, particularly preferably 1-50 mg, such as 1.5 mg, 2 mg, 4 mg, 10 mg, 25 mg, etc.; accordingly, the pharmaceutical composition of the present invention will contain 0.05 to 99% w/w (weight percentage), such as 0.05 to 80% w/w, such as 0.10 to 70% w/w, such as 0.10 to 50% w/w of the compound of the present invention, all weight percentages are based on the total composition. It should be understood that it may be necessary to use dosages exceeding these limits in certain circumstances.

In a specific embodiment, the present invention provides a pharmaceutical composition comprising a compound of the present invention and one or more pharmaceutically acceptable excipients, the composition being formulated for oral administration. The composition can be provided in a unit dosage form, for example in the form of a tablet, capsule or oral liquid preparation. Such a unit dosage form can contain 0.1 mg to 1 g, for example 5 mg to 250 mg of a compound of the present invention as an active ingredient.

In one embodiment, the present invention provides a pharmaceutical composition comprising a compound of the present invention and one or more pharmaceutically acceptable excipients, the composition being formulated for topical administration. Topical administration may be in the form of, for example, a cream, lotion, ointment or transdermal patch.

In a specific embodiment, the present invention provides a pharmaceutical composition comprising a compound of the present invention and one or more pharmaceutically acceptable excipients, the composition being formulated for inhalation administration. Inhalation administration can be by oral inhalation, or by intranasal administration. When administered by oral inhalation, the compound of the present invention can be effectively used in the present invention with a daily dose, for example, up to 500 μg, such as 0.1-50 μg, 0.1-40 μg, 0.1-30 μg, 0.1-20 μg or 0.1-10 μg of the compound of the present invention. The pharmaceutical composition of the present invention for oral inhalation can be formulated into a dry powder, a suspension (in a liquid or gas) or a solution (in a liquid), and can be administered in any suitable form and using any suitable inhaler device known in the art, including, for example, a metered dose inhaler (MDI), a dry powder inhaler (DPI), a nebulizer and a soft mist inhaler. A multi-chamber device can be used to deliver the compound of the present specification and one or more other active ingredients (when present).

Treatments and uses

Based on the beneficial effects of the compounds of the present invention, the compounds of the present invention can be used in methods for treating various diseases in animals, especially mammals such as humans.

Therefore, in another aspect, the present invention provides a method for regulating, especially inhibiting RET activity, which comprises contacting a cell with a compound of the present invention as described above to regulate, especially inhibit RET activity in the cell.

On the other hand, the present invention provides a method for preventing or treating a disease associated with RET (e.g., a disease treatable or preventable by RET inhibition), which comprises administering to an individual in need thereof an effective amount of a compound of the present invention as described above or a pharmaceutical composition of the present invention comprising the same.

In another aspect, the present invention provides use of the compound of the present invention as described above or a pharmaceutical composition comprising the same, for inhibiting RET activity, or for treating and/or preventing a disease associated with RET, such as a disease treatable or preventable by RET inhibition.

On the other hand, the present invention also provides the use of the above-mentioned compound of the present invention or a pharmaceutical composition comprising the same in the preparation of a drug, especially in a drug having RET receptor inhibitor activity.

On the other hand, the present invention provides the use of a compound of the present invention as described above or a pharmaceutical composition comprising the same in the preparation of a medicament for treating or preventing a disease associated with RET, such as a disease treatable or preventable by RET inhibition, wherein the compound or pharmaceutical composition is optionally combined with one or more chemotherapies or immunotherapies.

Synthesis of the compounds of the present invention

The present invention also provides a method for preparing a compound of formula (I), and the following illustrates a general synthetic scheme for synthesizing the compounds of the present invention. For each reaction step, appropriate reaction conditions are known to those skilled in the art or can be routinely determined. If not otherwise specified, the raw materials and reagents used in the preparation of these compounds are generally commercially available, or can be prepared by the following method, a method similar to the method given below, or a method known in the art. If necessary, the raw materials and intermediates in the synthetic reaction flow can be separated and purified using conventional techniques, including but not limited to filtration, distillation, crystallization, chromatography, etc. The materials can be characterized using conventional methods including physical constants and spectral data.

Synthesis Scheme 1:

The compounds of the present invention can be synthesized by a method comprising the following steps:

Reacting a compound of formula I-1 with a compound of formula I-3 to obtain a compound of formula (I);

The reaction can be carried out in the presence of a condensing agent, which is a condensing agent well known in the art for coupling carboxylic acids and amines, including but not limited to 1-propylphosphoric anhydride (T3P), EDC, DCC, HATU, EDCI, etc.; the reaction is preferably carried out in a suitable organic solvent, which can be selected from dichloromethane, tetrahydrofuran, ethers (such as diethyl ether, ethylene glycol monomethyl ether, etc.), N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, 1,4-dioxane, dimethyl sulfoxide and any combination thereof; the reaction is preferably carried out in the presence of a suitable base, which includes but is not limited to sodium carbonate, potassium carbonate, cesium carbonate, N,N-diisopropylethylamine, triethylamine, HOBt or pyridine, preferably, the base is N,N-diisopropylethylamine; the reaction is preferably carried out at a suitable temperature, such as 0-200°C, 10-100°C, 20-50°C or room temperature (20-25°C).

Synthesis Scheme 2:

when

The compounds of the present invention can be synthesized by a method comprising the following steps:

The compound of formula I-2 and the compound of formula I-3 are reacted with triphosgene or CDI to obtain a compound of formula (I-i);

The reaction is preferably carried out in a suitable organic solvent, which may be selected from dichloromethane, tetrahydrofuran, ethers (e.g., diethyl ether, ethylene glycol monomethyl ether, etc.), N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, 1,4-dioxane, dimethyl sulfoxide and any combination thereof, and optionally contains water; the reaction is preferably carried out in the presence of a suitable base, which includes but is not limited to sodium carbonate, sodium bicarbonate, potassium carbonate, cesium carbonate, N,N-diisopropylethylamine, triethylamine, HOBt or pyridine, preferably, the base is N,N-diisopropylethylamine; the reaction is preferably carried out at a suitable temperature, such as 0-200°C, 10-100°C, 20-50°C or room temperature (20-25°C).

The above synthesis schemes only list the preparation methods of some compounds in the present invention. The compounds of the present invention or their stereoisomers, tautomers, stable isotope derivatives, pharmaceutically acceptable salts or solvates can be prepared by a variety of methods, including the methods given above, the methods given in the examples or similar methods, by ordinary technicians in the field on the basis of the above synthesis schemes, combined with conventional techniques in the field.

DETAILED DESCRIPTION

The technical solution of the present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to these embodiments. Any changes or equivalent substitutions that do not deviate from the concept of the present invention are included in the protection scope of the present invention.

The experimental methods in the following examples where specific conditions are not specified are generally based on conventional conditions for such reactions or conditions recommended by the manufacturer. Unless otherwise specified, percentages and parts are weight percentages and weight parts, respectively. Unless otherwise specified, the ratios of liquids are volume ratios.

Unless otherwise specified, the experimental materials and reagents used in the following examples can be obtained from commercial channels, prepared according to methods in the prior art, or prepared according to methods similar to those disclosed in this application.

The abbreviations used in this application have the meanings commonly understood in the art, unless otherwise clearly defined in the specification. The meanings of the abbreviations used in the specification are listed below:

Pd(dppf)Cl ₂ :[1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride

Pd(dppf)Cl ₂ .DCM:[1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride dichloromethane complex

HATU:2-(7-Azobenzotriazole)-N,N,N’,N’,-tetramethyluronium hexafluorophosphate

DIEA: N,N-Diisopropylethylamine

DCM: dichloromethane

EA: Ethyl acetate

PE:Petroleum ether

DMF: N,N-dimethylformamide

TEA:Triethylamine

LC-MS: Liquid chromatography-mass spectrometry

ESI: Electrospray ionization

m/z: mass-to-charge ratio

EDCI:1-Ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride

HOBt:1-Hydroxybenzotriazole

CDI: N',N-Carbonyldiimidazole

Ret.time: retention time

HPLC: High Performance Liquid Chromatography

Synthesis Example

In the preparation method of the target compound provided by the present invention, the column chromatography uses silica gel (300-400 mesh) produced by Rushan Sun Desiccant Co., Ltd.; the thin layer chromatography uses GF254 (0.25 mm); the nuclear magnetic resonance chromatography (NMR) uses a Varian-400 nuclear magnetic resonance instrument for determination; and the liquid chromatography-mass spectrometry (LC/MS) uses an Agilent TechnologiESI 6120 liquid chromatography-mass spectrometer.

In addition, all operations involving raw materials that are easily oxidized or hydrolyzed are performed under nitrogen protection. Unless otherwise specified, the raw materials used in the present invention are commercially available raw materials and can be used directly without further purification. The temperatures used in the present invention are all degrees Celsius.

When the structure of a compound of the present invention is inconsistent with the compound name, the structural formula shall prevail unless the compound name can be determined to be correct from the context.

Example 1: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1-methyl-1H-pyrazole-5-carboxamide (Compound 1)

Step 1: Synthesis of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate

4-Hydroxy-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (500 mg, 2.09 mmol) and TEA (0.581 mL, 4.18 mmol) were added to DCM (10.0 mL). Under nitrogen protection and in an ice bath, trifluoromethanesulfonic anhydride (0.520 mL, 3.14 mmol) was added dropwise to the reaction solution. After the addition was completed, the reaction mixture was stirred and reacted for 1.5 hours in an ice bath. The organic solvent was removed by concentration under reduced pressure to obtain the target compound (600 mg, crude product, black oil). LC-MS (ESI) m/z 370.0 [MH] ^- .

Step 2: Synthesis of methyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-methyl-1H-pyrazole-5-carboxylate

3-Cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (300 mg, 0.808 mmol), (5-(methoxycarbonyl)-1-methyl-1H-pyrazol-3-yl)boronic acid (163 mg, 0.889 mmol), potassium carbonate (223 mg, 1.62 mmol) and Pd(dppf)Cl ₂ (59.1 mg, 0.081 mmol) were added to a mixed solvent of 1,4-dioxane (8 mL) and water (1 mL). Under nitrogen protection, the reaction mixture was stirred at 100°C for 3 hours. The reaction mixture was cooled to room temperature and filtered. Water (15 mL) was added to the filtrate, and extracted with EA (10 mL x 2). The organic phases were combined, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (95.0 mg, two-step yield 25.2%, brown-yellow solid) was obtained by separation and purification on a preparative plate (DCM:methanol=20:1). LC-MS (ESI) m/z 362.1 [M+H] ⁺ .

Step 3: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-methyl-1H-pyrazole-5-carboxylic acid

3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-methyl-1H-pyrazole-5-carboxylic acid methyl ester (120 mg, 0.332 mmol) was dissolved in a mixed solvent of tetrahydrofuran (2 mL) and methanol (2 mL). At room temperature, an aqueous sodium hydroxide solution (1 mol/L, 1 mL) was added dropwise. The reaction mixture was stirred at room temperature for overnight reaction. The reaction solution was adjusted to pH ~ 4 with dilute hydrochloric acid (1 mol/L). The crude product was concentrated under reduced pressure. A mixed solution of DCM and methanol (20 mL, v:v = 10:1) was added to the crude product and stirred at room temperature for 10 minutes. Filtered, the filtrate was concentrated under reduced pressure to obtain the target compound (110 mg, yield 95.4%, brown solid). LC-MS (ESI) m/z [M + H] ⁺ 348.1.

Step 4: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1-methyl-1H-pyrazole-5-carboxamide

3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-methyl-1H-pyrazole-5-carboxylic acid (70.0 mg, 0.202 mmol), 6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (46.5 mg, 0.242 mmol), DIEA (0.100 mL, 0.604 mmol) and HATU (115 mg, 0.302 mmol) were added to DMF (3 mL). The reaction mixture was stirred at room temperature for overnight reaction. The reaction solution was poured into water (15 mL) and extracted with EA (10 mL x 2). The organic phases were combined, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. Washed with methanol and filtered to obtain the target compound (10.0 mg, yield 9.52%, brown solid). LC-MS(ESI)m/z 522.1[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.29–9.20(m,2H),8.69–8.64(m,2H),8.45(s,1H),8.38(s,1H),8.10(s,1H),8.00–7.93(m,2H),7.93–7.85(m,2H),7.41( s, 1H), 4.53 (d, J = 5.7Hz, 2H), 4.16 (s, 3H), 3.87 (s, 3H).

Example 2: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-5-carboxamide (Compound 2)

Step 1: Synthesis of methyl 3-hydroxy-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylate

(4-Methoxybenzyl)hydrazine hydrochloride (2.46 g, 14.1 mmol) and TEA (4.40 mL, 31.7 mmol) were added to a mixed solvent of water (10.0 mL) and methanol (20.0 mL). The reaction mixture was stirred at 0°C for 15 minutes, and dimethyl succinate (2.00 g, 14.1 mmol) was added. The reaction mixture was stirred at 80°C for 4 hours. The reaction solution was concentrated under reduced pressure to obtain a crude product. The crude product was added to water (30.0 mL), filtered, and the filter cake was washed with water (10.0 mL). The filter cake was dried under vacuum to obtain the target product (2.70 g, yield 73.2%, yellow solid). LC-MS (ESI) m/z 263.0 [M+H] ⁺ .

Step 2: Synthesis of methyl 1-(4-methoxybenzyl)-3-(((trifluoromethyl)sulfonyl)oxy)-1H-pyrazole-5-carboxylate

At 0°C, trifluoromethanesulfonic anhydride (5.81 g, 20.6 mmol) was added to a solution of 3-hydroxy-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylic acid methyl ester (2.70 g, 10.3 mmol) and TEA (2.86 mL, 20.6 mmol) in DCM (25.0 mL). The reaction mixture was stirred at room temperature for 1 hour. Saturated aqueous sodium bicarbonate solution (20.0 mL) was added to the reaction solution. The organic phase was separated and the aqueous phase was extracted with DCM (50.0 mL × 2). The organic phases were combined, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (2.45 g, yield 60.3%, yellow solid) was obtained by column chromatography separation and purification (PE: EA = 100: 1-15: 1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ7.17 (d, J = 8.7 Hz, 2H), 7.09 (s, 1H), 6.90 (d, J = 8.7 Hz, 2H), 5.61 (s, 2H), 3.86 (s, 3H), 3.72 (s, 3H).

Step 3: Synthesis of methyl 1-(4-methoxybenzyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole-5-carboxylate

Potassium acetate (560 mg, 5.71 mmol), 1,1'-bis(diphenylphosphino)ferrocene (52.7 mg, 0.095 mmol) and Pd(dppf)Cl 2 DCM complex (81.9 mg, 0.095 mmol) were added to a solution of 1-(4-methoxybenzyl)-3-(((trifluoromethyl)sulfonyl)oxy)-1H-pyrazole-5-carboxylic acid methyl ester (750 mg, 1.90 mmol) and biboronic acid pinacol ester (531 mg, 2.09 mmol) in _1,4 -dioxane (10.0 mL). The reaction mixture was stirred at 100°C for 16 hours under argon protection. The reaction solution was cooled to room temperature and poured into EA (80.0 mL) to obtain a black solution. The solution was filtered through celite and the filter cake was washed with EA (20.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (600 mg, yield 84.7%, black solid). LC-MS (ESI) m/z 291.0 [M-82+H] ⁺ .

Step 4: Synthesis of methyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylate

Potassium carbonate (372 mg, 2.69 mmol) and Pd(dppf)Cl 2 DCM complex (58.0 mg, 0.067 mmol) were added to a mixed solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (500 mg, 1.35 mmol) and 1-(4-methoxybenzyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole- ₅ -carboxylic acid methyl ester (551 mg, 1.48 mmol) in DMF (6.00 mL). Under argon protection, the reaction mixture was stirred at 100°C for 5 hours. The reaction mixture was cooled to room temperature and poured into water (20.0 mL), and extracted with EA (60.0 mL×2). The combined organic phases were washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (210 mg, yield 33.4%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=5:1-1:1). LC-MS (ESI) m/z 468.2 [M+H] ⁺ .

Step 5: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylic acid

Lithium hydroxide (21.5 mg, 0.898 mmol) was added to a mixed solution of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylic acid methyl ester (210 mg, 0.449 mmol) in water (1.00 mL), tetrahydrofuran (2.00 mL), and methanol (4.00 mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to remove the organic solvent, and then dissolved in water (10.0 mL). The pH was adjusted to 5 with 1.0 M hydrochloric acid solution to obtain a suspension. The suspension was filtered and the filter cake was washed with water (5.00 mL). The target compound (185 mg, yield 90.8%, yellow solid) was obtained after vacuum drying. LC-MS(ESI)m/z 454.1[M+H] ⁺ .

Step 6: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxamide

EDCI (56.9 mg, 0.298 mmol), HOBt (38.5 mg, 0.298 mmol) and DIEA (51.3 mg, 0.397 mmol) were added to a solution of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxylic acid (90.0 mg, 0.198 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methanamine (45.7 mg, 0.238 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was poured into water (15.0 mL) and extracted with EA (60.0 mL×2). The combined organic phases were washed with saturated brine (15.0 mL x 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure and dried in vacuo to obtain the target compound (150 mg, crude product, yellow solid). LC-MS (ESI) m/z 628.0 [M+H] ⁺ .

Step 7: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-5-carboxamide

A solution of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1-(4-methoxybenzyl)-1H-pyrazole-5-carboxamide (150 mg, 0.239 mmol) in trifluoroacetic acid (5.00 mL) was stirred at 70°C for 1 hour. The reaction solution was spin-dried and dissolved in methanol (5.00 mL), and added dropwise to a saturated sodium bicarbonate solution (20.0 mL) to obtain a yellow suspension. The filter cake was filtered and washed with clean water (10.0 mL), and purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid) to obtain the target compound (9.30 mg, two-step yield 8.47%, yellow solid). LC-MS(ESI)m/z 508.1[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ14.00(s,1H),9.32(s,1H),9.13(s,1H),8.72–8.65(m,2H),8.47–8.44(m,1H),8.40(s,1H),8.13(s,1H),8.01–7.95(m,2H ),7.93–7.89(m,2H),7.26(s,1H),4.55(d,J=5.5Hz,2H),3.89(s,3H).

Example 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperazine-1-carboxamide (Compound 3) and its hydrochloride (Compound 3-1)

Step 1: Synthesis of tert-butyl 4-(5-bromopyridin-3-yl)piperazine-1-carboxylate

Potassium carbonate (7.85 g, 56.8 mmol) was added to a solution of 3-bromo-5-fluoropyridine (5.00 g, 28.4 mmol) and tert-butyl piperazine-1-carboxylate (7.94 g, 42.6 mmol) in N-methylpyrrolidone (50.0 mL). The reaction mixture was stirred at 100 °C for 16 hours and then stirred at 120 °C for 5 hours. The reaction mixture was cooled to room temperature and poured into water (100 mL) and extracted with EA (250 mL). The organic phase was washed with saturated brine (50.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.30 g, yield 13.3%, yellow solid) was obtained by column chromatography separation and purification (PE: EA = 20: 1-10: 1). LC-MS (ESI) m/z 342.1, 344.1 [M+H] ⁺ .

Step 2: Synthesis of 1-amino-3-bromo-5-(4-tert-butoxycarbonyl)piperazin-1-yl)pyridin-1-ium-2,4,6-trimethylbenzenesulfonate

4-(5-bromopyridin-3-yl)piperazine-1-carboxylic acid tert-butyl ester (2.30 g, 6.72 mmol) and 2,4,6-trimethylbenzenesulfonylhydroxylamine (1.74 g, 8.06 mmol) were added to DCM (20.0 mL). The reaction mixture was stirred at 0°C for 1 hour. The reaction solution was concentrated under reduced pressure to obtain the target compound (3.75 g, crude product, yellow solid). LC-MS (ESI) m/z 357.1, 359.2 [M] ⁺ .

Step 3: Synthesis of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)piperazine-1-carboxylate

At 0°C, acrylonitrile (1.01 mL, 15.5 mmol) and DIEA (1.45 mL, 8.75 mmol) were added to a solution of 1-amino-3-bromo-5-(4-tert-butoxycarbonyl)piperazin-1-yl)pyridin-1-ium-2,4,6-trimethylbenzenesulfonate (3.75 g, 6.73 mmol) in 1,4-dioxane (35.0 mL). The reaction solution was stirred at 0°C for 2 hours, and then 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (3.21 g, 14.1 mmol) was added. The reaction solution was stirred at 0°C for 1 hour, and then the mixture was heated to room temperature and stirred for 16 hours. The reaction mixture was concentrated under reduced pressure, and water (60.0 mL) was added to the residue, which was extracted with EA (250 mL). The organic phase was washed with saturated brine (30.0 mL × 5), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.20 g, two-step yield 43.9%, yellow solid) was obtained by column chromatography separation and purification (PE: EA = 100: 1-9: 1). LC-MS (ESI) m/z 306.1, 308.1 [M-100 + H] ⁺ .

Step 4: Synthesis of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperazine-1-carboxylate

Sodium carbonate (104 mg, 0.984 mmol) and Pd(dppf)Cl 2 (16.0 mg, 0.025 mmol) were added to a mixed solution of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)piperazine- ₁ -carboxylate (200 mg, 0.492 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (123 mg, 0.591 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL). The argon atmosphere was replaced three times, and the reaction mixture was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (50.0 mL), and extracted with EA (100 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (155 mg, yield 77.5%, yellow oil) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 408.3 [M+H] ⁺ . ¹ HNMR (400 MHz, DMSO-d ₆ ) δ 8.92 (d, J=1.1 Hz, 1H), 8.58 (s, 1H), 8.34 (s, 1H), 8.06 (d, J=0.6 Hz, 1H), 7.30 (d, J=1.1 Hz, 1H), 3.87 (s, 3H), 3.65–3.54 (m, 4H), 3.12–3.05 (m, 4H), 1.43 (s, 9H).

Step 5: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(piperazin-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperazine-1-carboxylic acid tert-butyl ester (150 mg, 0.368 mmol) was added to a methanol solution of hydrogen chloride (3.0 M, 8.00 mL). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (130 mg, yield 99.2%, off-white solid). LC-MS (ESI) m/z 308.2 [M+H] ⁺ .

Step 6: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperazine-1-carboxamide and its hydrochloride

To a mixture of saturated sodium bicarbonate aqueous solution (3.00 mL) and DCM (5.00 mL) were added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (30.3 mg, 0.158 mmol) and triphosgene (28.1 mg, 0.095 mmol) in sequence. The reaction mixture was stirred at room temperature for 1 hour. The organic phase was separated and the aqueous phase was extracted with DCM (4.00 mL). The combined organic phases were washed with saturated brine (5.00 mL × 2), dried over anhydrous sodium sulfate, and filtered. TEA (0.065 mL, 0.573 mmol) and 6-(1-methyl-1H-pyrazol-4-yl)-4-(piperazine-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (65.0 mg, 0.189 mmol) were added to the filtrate in sequence. The mixture was stirred at room temperature for 15 minutes. The reaction solution was concentrated under reduced pressure to obtain a crude product (Compound 3) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 3-1) in the form of hydrochloride (18.2 mg, yield 17.2%, yellow solid). LC-MS (ESI) m/z 526.3 [M+H] ⁺ . ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 8.68 (s, 1H), 8.62–8.23 (m, 4H), 8.24–7.87 (m, 3H), 7.77 (s, 1H), 7.25 (s, 1H), 4.46 (s, 2H), 4.09-3.96 (m, 3H), 3.85–3.63 (m, 4H), 3.27–3.11 (m, 4H).

Example 4: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-4-methylpiperidine-4-carboxamide (Compound 4) and its hydrochloride (Compound 4-1)

Step 1: Synthesis of 1-amino-3-bromo-5-fluoropyridin-1-ium 2,4,6-trimethylbenzenesulfonate

3-Bromo-5-fluoropyridine (10.0 g, 56.8 mmol) and O-2,4,6-trimethylbenzenesulfonylhydroxylamine (14.7 g, 68.2 mmol) were added to DCM (150 mL). The reaction mixture was stirred at 0°C for 1 hour. PE (150 mL) was slowly added to the reaction solution at 0°C and stirred for 15 minutes to obtain a white suspension. After filtration, the product (15.5 g, white solid) and crude product (5.50 g, white solid) were obtained. LC-MS (ESI) m/z 191.1, 193.1 [M] ⁺ .

Step 2: Synthesis of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile

At 0°C, add acrylonitrile (7.74mL, 118mmol) and DIEA (11.0mL, 66.4mmol) to a solution of 1-amino-3-bromo-5-fluoropyridin-1-ium 2,4,6-trimethylbenzenesulfonate (20.0g, 51.1mmol) in 1,4-dioxane (200mL). After the reaction solution was stirred at 0°C for 2 hours, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (23.2g, 102mmol) was added. The reaction solution was stirred at 0°C for 1 hour, and then warmed to room temperature and continued to react for 16 hours. The reaction mixture was poured into ice water (300mL) to obtain a brown suspension. The suspension was stirred at room temperature for 20 minutes and then filtered, and the filter cake was washed with ice water (100mL) to obtain a solid crude product. The title compound (5.70 g, two-step yield 41.9%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=100:1-10:1).

Step 3: Synthesis of ethyl 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylate

Potassium carbonate (576 mg, 4.17 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (400 mg, 1.67 mmol) and ethyl 4-methylpiperidine-4-carboxylate hydrochloride (380 mg, 1.83 mmol) in N-methylpyrrolidone (2.00 mL). The reaction mixture was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (25.0 mL) and extracted with EA (100.0 mL). The organic phase was washed with saturated brine (20.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product, which was separated and purified by column chromatography (PE:EA=12:1-10:1) to obtain the target compound (600 mg, yield 81.9%, off-white solid). LC-MS(ESI)m/z 390.9,393.1[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.96(d,J＝1.3Hz,1H),8.62(s,1H),7.15(d,J＝1.3Hz,1H),4.14(q,J＝7.1Hz,2H),3.30–3.21(m,2H),2.92–2.81(m,2H),2.22– 2.11(m,2H),1.79–1.69(m,2H),1.26–1.20(m,6H).

Step 4: Synthesis of ethyl 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylate

Sodium carbonate (325 mg, 3.07 mmol) and Pd(dppf)Cl 2 DCM complex (66.0 mg, 0.077 mmol) were added to a mixed solution of 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine- ₄ -carboxylic acid ethyl ester (600 mg, 1.53 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (383 mg, 1.84 mmol) in water (1.50 mL) and 1,4-dioxane (7.50 mL). The argon atmosphere was replaced three times, and the reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (25.0 mL), and extracted with EA (60.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (490 mg, yield 81.3%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-2:1). LC-MS (ESI) m/z 393.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.89(d,J＝1.0Hz,1H),8.56(s,1H),8.38(s,1H),8.07(s,1H),7.25(d,J＝0.9Hz,1H),4.15(q,J＝7.1Hz,2H),3.87(s,3H),3.31 –3.24(m,2H),2.94–2.82(m,2H),2.26–2.16(m,2H),1.82–1.71(m,2H),1.26–1.20(m,6H).

Step 5: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylic acid

Sodium hydroxide (61.2 mg, 1.53 mmol) was added to an ethanol solution (10.0 mL) of ethyl 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylate (200 mg, 0.509 mmol). The reaction mixture was stirred at 80°C for 20 hours. The reaction mixture was concentrated under reduced pressure to remove the organic solvent and then added to water (10.0 mL). A brown suspension was obtained after adjusting the pH to 3 with a 3.0 M dilute hydrochloric acid solution. The filter cake was filtered, washed with water (15.0 mL), and dried to obtain the target compound (140 mg, yield 75.3%, brown solid). LC-MS (ESI) m/z 365.0 [M+H] ⁺ .

Step 6: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-4-methylpiperidine-4-carboxamide and its hydrochloride

To a solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylic acid (140 mg, 0.384 mmol) in DMF (2.00 mL) at room temperature were added EDCI (110 mg, 0.576 mmol), HOBt (77.8 mg, 0.576 mmol), DIEA (99.3 mg, 0.768 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (73.8 mg, 0.384 mmol). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was poured into water (20.0 mL) and extracted with EA (60.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 4) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 4-1) in the form of hydrochloride (68.1 mg, yield 30.9%, yellow solid). LC-MS (ESI) m/z 539.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.87(s,1H),8.65-8.63(m,1H),8.55(s,1H),8.42–8.38(m,1H),8.37(s,1H),8.35-8.34(m,1H),8.06(s,1H),7.90-7.88(m, 1H),7.88-7.86(m,2H),7.21(s,1H),4.37(d,J＝5.8Hz,2H),3.86(s,3H),3.26–3.20(m,2H),2.95–2.88(m,2H),2.28–2.23(m,2H),1.77–1.71(m,2H) ,1.21(s,3H).

Example 5: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethyl)-4-methylpiperidine-4-carboxamide (Compound 5) and its hydrochloride (Compound 5-1)

To a solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-4-methylpiperidine-4-carboxylic acid (100 mg, 0.274 mmol) in DMF (2.00 mL) at room temperature were added EDCI (80.0 mg, 0.412 mmol), HOBt (55.7 mg, 0.412 mmol), DIEA (70.9 mg, 0.549 mmol) and 1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethan-1-amine (56.6 mg, 0.274 mmol). The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was poured into water (15.0 mL) and extracted with EA (60.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 5) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 5-1) in the form of hydrochloride (65.2 mg, yield 40.4%, gray solid). LC-MS (ESI) m/z 553.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.86 (d, J = 0.7 Hz, 1H), 8.65 (d, J = 4.0 Hz, 1H), 8.56 (s, 1H), 8.41 (d, J = 2.0 Hz, 1H), 8.37 (s, 1H), 8.12 (d, J = 7.7 Hz, 1H), 8.06 (s, 1H), 7.97–7.93 (m, 1H), 7.91–7.86 ( m,2H),7.19(s,1H),5.14–5.05(m,1H),3.87(s,3H),3.29–3.18(m,2H),2.97–2.82(m,2H),2.36–2.19(m,2H),1.80–1.67(m,2H),1.46(d,J＝7.1Hz,3 H),1.21(s,3H).

Example 6: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxamide ( Compound 6)

Step 1: Synthesis of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxylate

Potassium carbonate (577 mg, 4.18 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (400 mg, 1.67 mmol) and tert-butyl 3,6-diazabicyclo[3.1.1]heptane-6-carboxylate (398 mg, 2.01 mmol) in N-methylpyrrolidone (5.00 mL). The tube was sealed and the reaction mixture was stirred at 100°C for 16 hours. After the reaction mixture was cooled to room temperature, it was poured into water (20.0 mL) and extracted with EA (20.0 mL×3). The organic phases were combined, washed with saturated brine (20.0 mL×3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (75.0 mg, yield 11.0%, white solid) was obtained by column chromatography separation and purification (PE:EA=85:15). LC-MS(ESI)m/z 418.1,420.1[M+H] ⁺ .

Step 2: Synthesis of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxylate

To a solution of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxylate (75.0 mg, 0.179 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (44.9 mg, 0.218 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL) were added sodium carbonate (38.1 mg, 0.359 mmol) and Pd(dppf)Cl ₂ DCM complex (7.80 mg, 0.009 mmol). The reaction mixture was stirred at 80°C for 16 hours under argon protection. The reaction mixture was cooled to room temperature and poured into water (10.0 mL), and extracted with EA (10.0 mL × 3). The combined organic phases were washed with saturated brine (10.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (60.0 mg, yield 79.4%, white solid) was obtained by column chromatography separation and purification (PE: EA = 2: 3). LC-MS (ESI) m/z 420.2 [M + H] ⁺ . ² .64–2.59(m,1H),2.41-2.38(m,1H) _, 1.46(s,9H),1.34–1.23(m,4H).

Step 3: Synthesis of 4-(3,6-diazabicyclo[3.1.1]heptane-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile trifluoroacetate

To a DCM solution (2.00 mL) of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxylate (50.0 mg, 0.119 mmol) was added trifluoroacetic acid (0.500 mL) at 0°C. The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was concentrated under reduced pressure to give the target compound (50.0 mg, crude product, gray solid). LC-MS (ESI) m/z 320.2 [M+H] ⁺ .

Step 4: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-diazabicyclo[3.1.1]heptane-6-carboxamide

Triphosgene (61.4 mg, 0.207 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methanamine (66.3 mg, 0.345 mmol) in aqueous sodium bicarbonate (2.50 mL) and DCM (5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was extracted with DCM (10.0 mL). The organic phase was washed with saturated brine (4.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (69.8 mg, 0.690 mmol) and 4-(3,6-diazabicyclo[3.1.1]heptane-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile trifluoroacetate (50.0 mg, 0.157 mmol) were added to the filtrate. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was concentrated under reduced pressure to obtain a crude product. The target compound (Compound 6) (16.1 mg, two-step yield 25.1%, white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% ammonia). LC-MS (ESI) m/z 538.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.87(s,1H),8.57(s,1H),8.46(d,J＝4.3Hz,1H),8.34–8.30(m,2H),8.03(s,1H),7.88–7.82(m,2H),7.75–7.71(m,1H),7.35( t,J＝5.7Hz,1H),7.27(s,1H),4.34–4.27(m,4H),3.86(s,3H),3.79–3.74(m,2H),3.57–3.52(m,2H),3.23–3.15(m,1H),2.18(d,J＝7.9Hz,1H).

Example 7: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperidine-4-carboxamide (Compound 7) and its hydrochloride (Compound 7-1)

Step 1: Synthesis of ethyl 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylate

Anhydrous potassium carbonate (863 mg, 6.30 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (600 mg, 2.50 mmol) and ethyl piperidine-4-carboxylate hydrochloride (581 mg, 3.00 mmol) in N-methylpyrrolidone (6.00 mL). The tube was sealed and the reaction mixture was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and added to water (20.0 mL) and extracted with EA (60.0 mL). The organic phase was washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. Column chromatography separation and purification (EA:PE = 0:100--15:100) gave the target compound (280 mg, yield 29.7%, white solid). LC-MS(ESI)m/z 377.2,379.2[M+H] ⁺ .

Step 2: Synthesis of ethyl 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylate

Anhydrous sodium carbonate (67.7 mg, 0.640 mmol) and Pd(dppf)Cl 2 DCM complex (13.0 mg, 0.016 mmol) were added to a mixed solution of 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylic acid ethyl ester (120 mg, 0.318 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)-1H-pyrazole (79.7 mg, 0.383 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL). The argon atmosphere was replaced three times, and the reaction mixture was stirred at 80°C overnight. The reaction solution was cooled to room temperature, poured into water (10.0 mL), and extracted with EA (15.0 mL×3). The combined organic phases were washed with saturated brine (20.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (115 mg, yield 95.5%, white solid) was obtained by column chromatography separation and purification (EA:PE = 0:100-60:100). LC-MS (ESI) m/z 379.3 [M+H] ⁺ .

Step 3: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylic acid

To a mixed solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylic acid ethyl ester (115 mg, 0.304 mmol) in ethanol (8.00 mL) and water (2.00 mL) was added sodium hydroxide (36.5 mg, 0.913 mmol). The reaction mixture was stirred at room temperature for 4 hours. The organic solvent was removed by concentration under reduced pressure, water (10.0 mL) was added, and the pH was adjusted to 4 with a 1.0 M aqueous hydrochloric acid solution to obtain a suspension. The filter cake was filtered, washed with water (20.0 mL), and dried to obtain the target compound (100 mg, yield 93.9%, white solid). LC-MS (ESI) m/z 351.2 [M+H] ⁺ .

Step 4: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperidine-4-carboxamide and its hydrochloride

1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-4-carboxylic acid (100 mg, 0.285 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (54.9 mg, 0.285 mmol) were dissolved in DMF (8.00 mL). DIEA (73.8 mg, 0.571 mmol), EDCI (82.1 mg, 0.428 mmol) and HOBt (57.8 mg, 0.428 mmol) were added. The reaction mixture was stirred at room temperature for 16 hours. The reaction solution was slowly added to water (10.0 mL) and extracted with EA (10.0 mL×2). The organic phase was washed with saturated brine (10.0 mL×2), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 7) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 7-1) in the form of hydrochloride (6.92 mg, hydrochloride, yield 4.32%, white solid). LC-MS (ESI) m/z 525.4 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.88(s,1H),8.68(d,J＝4.4Hz,1H),8.58–8.50(m,2H),8.36(s,2H),8.06(s,1H),7.91(d,J＝4.1Hz,1H),7.88(s,2H),7.24(s,1 H),4.35(d,J＝5.5Hz,2H),3.87(s,3H),3.52–3.47(m,2H),2.80(t,J＝10.9Hz,2H),2.46–2.37(m,1H),2.06–1.93(m,2H),1.93–1.84(m,2H).

Example 8: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3-azabicyclo[3.2.1]octane-8-carboxamide (Compound 8)

Step 1: Synthesis of 3-benzyl-3-azabicyclo[3.2.1]octane-8-carbonitrile

3-Benzyl-3-azabicyclo[3.2.1]octan-8-one (5.95 g, 27.6 mmol) and p-toluenesulfonylmethyl isocyanide (9.70 g, 49.7 mmol) were added to 1,2-dichloroethane (185 mL). Under nitrogen protection, anhydrous ethanol (2.90 mL, 63.5 mmol) was added under ice bath, and potassium tert-butoxide (10.8 g, 96.6 mmol) was added in four portions. The reaction mixture was stirred at 50°C for 18 hours. The reaction mixture was cooled to room temperature, poured into a saturated aqueous sodium chloride solution (80 mL), and extracted with EA (100 mL×3). The organic phases were combined, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (3.85 g, yield 61.6%, white solid) was obtained by column chromatography separation and purification (PE:EA＝100:1-5:1). LC-MS (ESI) m/z 227.2 [M+H] ⁺ .

Step 2: Synthesis of ethyl 3-benzyl-3-azabicyclo[3.2.1]octane-8-carboxylate

3-Benzyl-3-azabicyclo[3.2.1]octane-8-carbonitrile (1.60 g, 7.07 mmol) was added to a hydrogen chloride ethanol solution (12.0 mL). The tube was sealed and the reaction mixture was stirred at 80°C for 16 hours. Hydrogen chloride ethanol solution (6.00 mL) was added and the reaction mixture was stirred at 80°C for 16 hours. After the reaction solution was cooled to room temperature, it was slowly poured into water (60.0 mL), the pH was adjusted to 8 with a saturated sodium bicarbonate solution, and extracted with EA (120 mL × 2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.05 g, yield 54.3%, colorless oil) was obtained by column chromatography separation and purification (PE:EA＝100:1). LC-MS(ESI)m/z 274.3[M+H] ⁺ .

Step 3: Synthesis of ethyl 3-azabicyclo[3.2.1]octane-8-carboxylate

Dissolve 3-benzyl-3-azabicyclo[3.2.1]octane-8-carboxylic acid ethyl ester (1.05 g, 3.84 mmol) in methanol (20.0 mL). Add palladium carbon (100 mg) and replace the hydrogen three times. The reaction mixture is stirred at room temperature for 16 hours. Filter, wash the filter cake with methanol (10.0 mL), and concentrate the filtrate under reduced pressure to obtain the target compound (690 mg, yield 97.8%, off-white solid). LC-MS (ESI) m/z 184.1 [M+H] ⁺ .

Step 4: Synthesis of ethyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylate

DIEA (646 mg, 5.00 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (600 mg, 2.50 mmol) and ethyl 3-azabicyclo[3.2.1]octane-8-carboxylate (550 mg, 3.00 mmol) in N-methylpyrrolidone (5.00 mL). The reaction mixture was stirred at 100°C for 16 hours. The reaction solution was cooled to room temperature and poured into water (20.0 mL) and extracted with EA (80.0 mL). The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (800 mg, yield 79.4%, off-white solid) was obtained by column chromatography separation and purification (PE:EA=20:1-10:1). LC-MS(ESI)m/z 403.1,405.1[M+H] ⁺ .

Step 5: Synthesis of ethyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylate

To a mixed solution of ethyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylate (300 mg, 0.744 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazole (186 mg, 0.893 mmol) in water (0.600 mL) and 1,4-dioxane (3.00 mL) were added sodium carbonate (158 mg, 1.49 mmol) and Pd(dppf)Cl ₂ (48.1 mg, 0.056 mmol). Under argon protection, the reaction mixture was stirred at 80°C for 16 hours. After cooling to room temperature, the reaction solution was poured into water (15.0 mL) and extracted with EA (25.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (120 mg, crude product, yellow oil) was obtained by column chromatography separation and purification (PE:EA=4:1-2:1). LC-MS (ESI) m/z 405.1 [M+H] ⁺ .

Step 6: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylic acid

3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylic acid ethyl ester (120 mg, 0.297 mmol) was dissolved in ethanol (5.00 mL) and sodium hydroxide (23.7 mg, 0.593 mmol) was added. The reaction mixture was stirred at room temperature for 3 hours. The reaction mixture was concentrated under reduced pressure, the residue was dissolved in water (6.00 mL), 1.0 M hydrochloric acid was added to adjust the pH to 4 to obtain a suspension, and filtered. The filter cake was washed with water (5.00 mL). The target compound (80.0 mg, two-step yield 71.4%, yellow solid) was obtained by vacuum drying. LC-MS (ESI) m/z 377.3 [M+H] ⁺ .

Step 7: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3-azabicyclo[3.2.1]octane-8-carboxamide

EDCI (61.2 mg, 0.319 mmol), HOBt (41.3 mg, 0.319 mmol) and DIEA (54.9 mg, 0.425 mmol) were added to a solution of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3-azabicyclo[3.2.1]octane-8-carboxylic acid (80.0 mg, 0.213 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (40.9 mg, 0.213 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was poured into water (10.0 mL) and extracted with EA (30.0 mL). The organic phase was washed with saturated brine (10.0 mL × 3), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (10.1 mg, yield 7.97%, yellow solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 551.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ8.90(s,1H),8.69(d,J＝4.5Hz,1H),8.59(s,1H),8.50-8.46(m,1H),8.37–8.33(m,2H),8.06(s,1H),7.94–7.88(m,2H),7.88–7.84(m,1H),7.30(s ,1H),4.35(d,J＝5.7Hz,2H),3.88(s,3H),3.48–3.43(m,2H),3.01–2.95(m,2H),2.72–2.67(m,2H),2.15–2.08(m,2H),1.70–1.63(m,2H),1.27–1.2 1(m,1H).

Example 9: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N -((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2-methylpiperazine-1-carboxamide (Compound 9)

Step 1: Synthesis of (S)-tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylate

Potassium carbonate (403 mg, 2.91 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (350 mg, 1.46 mmol) and (S)-2-methylpiperazine-1-carboxylic acid tert-butyl ester (292 mg, 1.46 mmol) in N-methylpyrrolidone (3.00 mL). The reaction mixture was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (15.0 mL) and extracted with EA (60.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (100 mg, yield 16.3%, off-white solid) was obtained by column chromatography separation and purification (PE:EA=12:1-10:1). LC-MS(ESI)m/z 364.0,366.0[M-100+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.04 (d, J = 1.3 Hz, 1H), 8.65 (s, 1H), 7.19 (d, J = 1.2 Hz, 1H), 4.37–4.25 (m, 1H), 3.78–3.72 (m, 1H), 3.62–3.50 (m, 2H), 3.30–3. 28(m,1H),3.19–3.13(m,1H),3.10–3.03(m,1H),1.43(s,9H),1.24(d,J＝6.7Hz,3H).

Step 2: Synthesis of (S)-tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylate

Sodium carbonate (50.5 mg, 0.476 mmol) and Pd(dppf)Cl 2 DCM complex (10.3 mg, 0.012 mmol) were added to a solution of (S)-4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylic acid tert-butyl ester (100 mg, 0.238 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)pyrazole (59.4 mg, 0.286 mmol) in water (0.200 mL) and 1,4-dioxane (1.00 mL). Under argon protection, the reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (60 mL×2) to obtain a black solution. It was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (90.0 mg, yield 89.7%, yellow oil) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 444.2 [M+Na] ⁺ .

Step 3: Synthesis of (S)-6-(1-methyl-1H-pyrazol-4-yl)-4-(3-methylpiperazin-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

(S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylic acid tert-butyl ester (90.0 mg, 0.214 mmol) was added to a methanol solution of hydrogen chloride (3.0 M, 6.00 mL). The reaction mixture was stirred at room temperature for 4 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (80.0 mg, yield 100%, yellow solid). LC-MS (ESI) m/z 322.1 [M+H] ⁺ .

Step 4: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2-methylpiperazine-1-carboxamide

Triphosgene (33.2 mg, 0.112 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (35.8 mg, 0.186 mmol) in saturated sodium bicarbonate aqueous solution (3.00 mL) and DCM (5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. The reaction solution was extracted with DCM (10.0 mL×1). The organic phase was washed with saturated brine (4.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (56.5 mg, 0.558 mmol) and (S)-6-(1-methyl-1H-pyrazol-4-yl)-4-(3-methylpiperazin-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (80.0 mg, 0.224 mmol) were added to the filtrate. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was concentrated under reduced pressure to obtain a crude product. The target compound (15.1 mg, yield 12.5%, white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 540.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.95 (s, 1H), 8.69 (d, J = 4.3Hz, 1H), 8.60 (s, 1H), 8.39–8.34 (m, 2H), 8.08 (s, 1H), 7.93–7.88 (m, 3H), 7.30 (s, 2H), 4.49–4.39 ( m,1H),4.37–4.27(m,2H),3.88(s,3H),3.83–3.74(m,1H),3.65–3.50(m,3H),3.29–3.20(m,1H),3.17–3.07(m,1H),1.27(d,J＝6.3Hz,3H).

Example 10: Synthesis of (R)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2-methylpiperazine-1-carboxamide (Compound 10 )

Step 1: Synthesis of (R)-tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylate

Potassium carbonate (346 mg, 2.50 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (300 mg, 1.25 mmol) and (R)-2-methylpiperazine-1-carboxylic acid tert-butyl ester (375 mg, 1.87 mmol) in N-methylpyrrolidone (2.00 mL). The reaction mixture was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (20.0 mL), and extracted with EA (20.0 mL×3). The combined organic phases were washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (80.0 mg, yield 15.2%, gray solid) was obtained by column chromatography separation and purification (PE:EA=9:1). LC-MS(ESI)m/z 364.0,366.0[M-56+H] ⁺ . ¹ H NMR (400MHz, CDCl ₃ ) δ8.42(d,J＝1.4Hz,1H),8.20(s,1H),6.87(d,J＝1.4Hz,1H),4.54–4.46(m,1H),3.95–3.88(m,1H),3.84–3.76(m,1H),3.67–3.61( m,1H),3.17–3.12(m,1H),3.05–3.00(m,1H),2.60–2.52(m,1H),1.48(s,9H),1.37(d,J＝6.8Hz,3H).

Step 2: Synthesis of (R)-tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylate

To a solution of (R)-4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylic acid tert-butyl ester (80.0 mg, 0.190 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazole (50.0 mg, 0.240 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL) were added sodium carbonate (42.0 mg, 0.396 mmol) and Pd(dppf)Cl ₂ DCM complex (8.00 mg, 0.009 mmol). Under nitrogen protection, the reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (20.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (70.0 mg, yield 89.1%, white solid) was obtained by column chromatography separation and purification (PE:EA=9:1-5:1). LC-MS (ESI) m/z 422.2 [M+H] ⁺ .

Step 3: Synthesis of (R)-6-(1-methyl-1H-pyrazol-4-yl)-4-(3-methylpiperazin-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

To a solution of (R)-tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2-methylpiperazine-1-carboxylate (76.0 mg, 0.166 mmol) in methanol (3.00 mL) was added a methanol solution of hydrogen chloride (3.0 M, 3.00 mL). The reaction mixture was stirred at room temperature for 12 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (50.0 mg, yield 84.2%, gray solid). LC-MS (ESI) m/z 322.1 [M+H] ⁺ .

Step 4: Synthesis of (R)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2-methylpiperazine-1-carboxamide

Triphosgene (20.8 mg, 0.070 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (22.4 mg, 0.116 mmol) in saturated sodium bicarbonate aqueous solution (3.00 mL) and DCM (5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. It was extracted with DCM (10.0 mL). The organic phase was washed with saturated brine (4.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (35.3 mg, 0.349 mmol) and (R)-6-(1-methyl-1H-pyrazol-4-yl)-4-(3-methylpiperazin-1-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (50.0 mg, 0.140 mmol) were added to the filtrate. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was concentrated under reduced pressure to obtain a crude product. The title compound (16.0 mg, yield 21.3%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 540.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 9.15 (d, J = 1.2 Hz, 1H), 8.98 (dd, J = 4.5, 0.7 Hz, 1H), 8.86 (s, 1H), 8.84 (s, 1H), 8.64 (s, 1H), 8.43-8.41 (m, 1H), 8.40-8.34 (m, 2H), 8.18 (d, J = 4.4 Hz, 1H), 7.75 (d, J = 1.0 Hz, 1H ),7.13-7.08(m,1H),5.04-5.00(m,1H),4.92(d,J＝5.9Hz,2H),4.39(s,3H),4.31–4.26(m,3H),4.17-4.11(m,1H),3.80-3.73(m,1H),3.70-3.64(m, 1H), 1.82 (d, J = 6.7Hz, 3H).

Example 11: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1- yl )pyridin-3-yl)methyl)-1,4-diazepane-1-carboxamide (Compound 11)

Step 1: Synthesis of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-1,4-diazepane-1-carboxylate

4-Fluoro-6-bromopyrazolo[1,5-a]pyridine-3-carbonitrile (1.00 g, 4.16 mmol) and tert-butyl 1,4-diazepane-1-carboxylate (1.00 g, 4.99 mmol) were dissolved in N-methylpyrrolidone (5.00 mL). DIEA (1.08 g, 8.32 mmol) was added to the reaction mixture. The reaction mixture was stirred at 90°C for 16 hours. After the reaction mixture was cooled to room temperature, it was poured into water (10.0 mL) and extracted with EA (15.0 mL×3). The combined organic phases were washed with saturated brine (10.0 mL×4), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (580 mg, yield 33.1%, light yellow solid) was obtained by column chromatography separation and purification (PE:EA＝12:1-10:1). LC-MS (ESI) m/z 442.1, 444.1 [M+Na] ⁺ . Step 2: Synthesis of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,4-diazepane-1-carboxylate

Potassium carbonate (164 mg, 1.19 mmol) and Pd(dppf)Cl 2 DCM complex (26.0 mg, 0.030 mmol) were added to a solution of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-1,4-diazepane-1-carboxylate (250 mg, 0.595 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)pyrazole (186 mg, 0.894 mmol) in water (0.500 mL) and 1,4-dioxane (3.00 mL). Under argon protection, the reaction mixture was stirred at 100°C for 6 hours. The reaction mixture was cooled to room temperature and poured into water (5.00 mL) and extracted with EA (10.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL × 2), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (145 mg, yield 57.8%, light yellow solid) was obtained by separation and purification with a reverse phase column (C18, acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 444.3 [M+Na] ⁺ .

Step 3: Synthesis of 4-(1,4-diazepan-1-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,4-diazepane-1-carboxylate (145 mg, 0.344 mmol) in methanolic hydrogen chloride (3.0 M, 10.0 mL) was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (120 mg, yield 97.5%, white solid). LC-MS (ESI) m/z 322.3 [M+H] ⁺ .

Step 4: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1,4-diazepane-1-carboxamide

To a mixture of aqueous sodium bicarbonate solution (3.00 mL) and DCM (5.00 mL) were added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (60.0 mg, 0.312 mmol) and triphosgene (55.8 mg, 0.188 mmol) in sequence. The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was extracted with DCM (10.0 mL). The organic phase was washed with saturated brine (5.00 mL×2), dried over anhydrous sodium sulfate, and filtered. TEA (94.8 mg, 0.936 mmol) and 4-(1,4-diazepan-1-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (120 mg, 0.335 mmol) were added to the filtrate in sequence. The reaction mixture was stirred at room temperature for 30 minutes. The reaction mixture was concentrated under reduced pressure to obtain a crude product. The target compound (23.81 mg, yield 13.2%, white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 540.3 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.90 (s, 1H), 8.66 (d, J = 4.1Hz, 1H), 8.57 (s, 1H), 8.36-8.33 (m, 2H), 8.05 (s, 1H), 7.96–7.79 (m, 3H), 7.35 (s, 1H), 7.14–7.0 1(m,1H),4.32(d,J＝4.9Hz,2H),3.86(s,3H),3.79–3.70(m,2H),3.60–3.51(m,2H),3.39–3.32(m,4H),2.18–2.00(m,2H).

Example 12: Synthesis of 1-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)azetidine-3-carboxamide (Compound 12)

Step 1: Synthesis of methyl 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylate

DIEA (1.16 g, 9.00 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (720 mg, 3.00 mmol) and azetidine-3-carboxylic acid methyl ester hydrochloride (500 mg, 3.30 mmol) in N-methylpyrrolidone (10.0 mL). The reaction mixture was stirred at 100°C for 8 hours. The reaction mixture was cooled to room temperature and poured into water (30.0 mL), stirred for 1 hour, and filtered. The filter cake was washed with water (10.0 mL) and dried to obtain the target compound (625 mg, yield 62.2%, light yellow solid). LC-MS (ESI) m/z 335.1,337.1 [M+H] ⁺ .

Step 2: Synthesis of methyl 1-(3-cyano-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylate

Potassium acetate (644 mg, 6.56 mmol) and Pd(dppf)Cl 2 DCM complex (141 mg, 0.164 mmol) were added to a solution of methyl 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin- ₄ -yl)azetidine-3-carboxylate (1.10 g, 3.28 mmol) and biboronic acid pinacol ester (4.17 g, 16.4 mmol) in dry 1,4-dioxane (20.0 mL). Under argon protection, the reaction mixture was stirred at 90°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Filtered, the filter cake was washed with EA (20.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (6.00 g, crude product, black solid). LC-MS (ESI) m/z 383.2 [M+H] ⁺ .

Step 3: Synthesis of methyl 1-(3-cyano-6-hydroxypyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylate

At 0°C, sodium hydroxide (2.51 g, 62.8 mmol) was added to a solution of 1-(3-cyano-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid methyl ester (6.00 g, 15.7 mmol) in tetrahydrofuran (200 mL). Then 30% hydrogen peroxide (12.8 mL, 126 mmol) was added dropwise. The reaction mixture was stirred at room temperature for 1 hour. Saturated aqueous ammonium chloride solution (100 mL) was added to the reaction mixture and stirred at room temperature for 15 minutes. The organic phase was separated and the aqueous phase was extracted with EA (80.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (320 mg, two-step yield 35.8%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=4:1-1:1). LC-MS (ESI) m/z 273.3 [M+H] ⁺ .

Step 4: Synthesis of 1-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid

To a solution of 1-(3-cyano-6-hydroxypyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid methyl ester (300 mg, 1.10 mmol) in tetrahydrofuran (6.00 mL) was added an aqueous sodium hydroxide solution (2.0 N, 1.10 mL, 2.20 mmol). The reaction mixture was stirred at room temperature for 15 minutes, and then 2,2-dimethyloxirane (0.983 mL, 11.0 mmol) was added. Under sealed conditions, the reaction mixture was stirred at 85°C for 8 hours. The reaction mixture was concentrated under reduced pressure to obtain a crude product. The target compound (80.0 mg, yield 22.0%, off-white solid) was purified by preparative HPLC (water/acetonitrile containing 0.05% formic acid). LC-MS (ESI) m/z 331.0 [M+H] ⁺ .

Step 5: Synthesis of 1-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)azetidine-3-carboxamide

EDCI (69.5 mg, 0.363 mmol), HOBt (49.1 mg, 0.363 mmol) and DIEA (62.6 mg, 0.484 mmol) were added to a DMF (2.00 mL) solution of 1-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid (80.0 mg, 0.242 mmol) and (6-methoxypyridin-3-yl)methylamine (40.2 mg, 0.291 mmol). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was poured into water (15.0 mL) and extracted with EA (100 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (21.9 mg, yield 20.0%, yellow solid) was obtained by preparative HPLC (water/acetonitrile containing 0.05% formic acid). LC-MS (ESI) m/z 451.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.56–8.51(m,1H),8.48(s,1H),8.16(d,J＝1.8Hz,1H),8.06(d,J＝2.2Hz,1H),7.62–7.58(m,1H),6.78(d,J＝8.5Hz,1H),6.35(d, J＝1.7Hz,1H),4.67(s,1H),4.34–4.29(m,2H),4.24(d,J＝5.7Hz,2H),4.16–4.11(m,2H),3.82(s,3H),3.78(s,2H),3.59–3.50(m,1H),1.21(s,6H).

Example 13: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)azetidine-3-carboxamide (Compound 13)

Step 1: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid

To a solution of 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid methyl ester (175 mg, 0.522 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (130 mg, 0.627 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL) was added sodium carbonate (111 mg, 1.04 mmol) and Pd(dppf)Cl ₂ DCM complex (22.5 mg, 0.026 mmol). Under nitrogen protection, the reaction mixture was stirred at 100°C for 4 hours. The reaction mixture was cooled to room temperature, concentrated, and then water (10.0 mL) was added. The pH was adjusted to about 4 with dilute hydrochloric acid (2.0 M) and filtered. The filter cake was dried to give the target compound (52.0 mg, yield 30.9%, off-white solid). LC-MS (ESI) m/z 323.2 [M+H] ⁺ .

Step 2: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)azetidine-3-carboxamide

To a solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid (50.0 mg, 0.155 mmol), (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (35.7 mg, 0.186 mmol), EDCI (44.6 mg, 0.232 mmol) and HOBt (31.4 mg, 0.232 mmol) in DMF (1.50 mL) was added DIEA (40.1 mg, 0.310 mmol) at room temperature. The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was poured into water (10.0 mL) and filtered. The filter cake was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid) to give the title compound (18.5 mg, yield 24.0%, white solid). LC-MS(ESI)m/z 497.3[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.75(s,1H),8.72–8.65(m,2H),8.56(s,1H),8.40–8.34(m,2H),8.07(s,1H),7.94–7.86(m,3H),6.80(s,1H),4.41–4.34(m ,4H),4.26–4.19(m,2H),3.88(s,3H),3.66–3.59(m,1H).

Example 14: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)azetidine-3-carboxamide (Compound 14)

Step 1: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)azetidine-3-carboxamide

EDCI (53.4 mg, 0.279 mmol), HOBt (37.7 mg, 0.279 mmol) and DIEA (48.1 mg, 0.372 mmol) were added to a solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-3-carboxylic acid (60.0 mg, 0.186 mmol) and (6-methoxypyridin-3-yl)methylamine (30.9 mg, 0.223 mmol) in DMF (1.50 mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was poured into water (15.0 mL) and extracted with EA (100 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (10.5 mg, yield 12.7%, off-white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 443.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.75–8.74(m,1H),8.58–8.53(m,2H),8.37(s,1H),8.07(s,2H),7.62–7.59(m,1H),6.80–6.76(m,2H),4.38–4.33(m,2H), 4.24(d,J＝5.7Hz,2H),4.23–4.18(m,2H),3.88(s,3H),3.82(s,3H),3.64–3.55(m,1H).

Example 15: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)azetidine-1-carboxamide (Compound 15)

Step 1: Synthesis of tert-butyl 3-(5-bromopyridin-3-yl)azetidine-1-carboxylate

To a solution of 3,5-dibromopyridine (5.50 g, 23.2 mmol) in anhydrous tetrahydrofuran (50.0 mL) was added (1-(tert-butyloxycarbonyl)azetidin-3-yl)zinc (II) iodide (8.65 g, 34.8 mmol) (dissolved in 100 mL of anhydrous tetrahydrofuran solution) and tetrakis(triphenylphosphine)palladium (2.68 g, 2.32 mmol). Under nitrogen protection, the reaction mixture was stirred at 60°C overnight. After the reaction solution was cooled to room temperature, a saturated ammonium chloride solution (50.0 mL) was added. Extracted with EA (75.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product. The crude product was separated and purified by column chromatography (C18, acetonitrile/water containing 0.05% formic acid). The crude product was added to a mixed solvent of PE and EA (5:1), stirred at room temperature for 2 hours, and filtered. The filter cake was dried in vacuo to obtain the target compound (1.40 g, yield 19.3%, white solid). LC-MS (ESI) m/z 313.2, 315.2 [M+H] ⁺ .

Step 2: Synthesis of 1-amino-3-bromo-5-(1-(tert-butyloxycarbonyl)azetidin-3-yl)pyridin-1-ium 2,4,6-trimethylbenzenesulfonate

Under ice bath, 2,4,6-trimethylsulfonylhydroxylamine (1.03 g, 4.78 mmol) was slowly added to a solution of tert-butyl 3-(5-bromopyridin-3-yl)azetidine-1-carboxylate (1.36 g, 4.34 mmol) in DCM (20.0 mL). The reaction mixture was stirred at 0°C for 4 hours. The mixture was concentrated under reduced pressure to obtain the target compound (2.50 g, crude product, white solid). LC-MS (ESI) m/z 369.1, 371.1 [M+CH ₃ CN] ⁺ .

Step 3: Synthesis of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)azetidine-1-carboxylate

At 0°C, acrylonitrile (577 mg, 10.9 mmol) and DIEA (795 mg, 6.15 mmol) were added to a solution of 1-amino-3-bromo-5-(1-(tert-butyloxycarbonyl)azetidin-3-yl)pyridin-1-ium 2,4,6-trimethylbenzenesulfonate (2.50 g, 4.73 mmol) in 1,4-dioxane (30.0 mL). After the reaction solution was stirred at 0°C for 2 hours, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (2.25 g, 9.91 mmol) was added. The reaction mixture was warmed to room temperature and stirred for 16 hours. The reaction mixture was poured into EA (20.0 mL) and then filtered to remove the residue. The filtrate was washed with a saturated sodium carbonate solution (60.0 mL × 5), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (570 mg, two-step yield 34.8%, pink solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 418.1, 420.1 [M+CH ₃ CN+H] ⁺ .

Step 4: Synthesis of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-1-carboxylate

Potassium carbonate (308 mg, 2.23 mmol) and Pd(dppf)Cl 2 DCM complex (48.0 mg, 0.0557 mmol) were added to a mixed solution of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin- ₄ -yl)azetidine-1-carboxylate (420 mg, 1.11 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (255 mg, 1.23 mmol) in water (0.500 mL) and 1,4-dioxane (5.00 mL). Under argon protection, the reaction mixture was stirred at 90°C for 8 hours. After the reaction solution was cooled to room temperature, EA (15.0 mL) was added to the reaction solution, which was then dried over anhydrous sodium sulfate and filtered. The solution was concentrated under reduced pressure to obtain a crude product. The target compound (400 mg, yield 94.7%, light yellow solid) was obtained by column chromatography separation (PE:EA=1:1-1:3). LC-MS (ESI) m/z 279.1 [M-100+H] ⁺ .

Step 5: Synthesis of 4-(azetidin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)azetidine-1-carboxylate (220 mg, 0.581 mmol) in methanolic hydrogen chloride (3.0 M, 8.00 mL) was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure to give the target compound (180 mg, yield 98.4%, white solid). LC-MS (ESI) m/z 279.1 [M+H] ⁺ .

Step 6: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)azetidine-1-carboxamide

To a solution of CDI (60.3 mg, 0.372 mmol) in DMF (2.00 mL) were added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (65.9 mg, 0.343 mmol) and DIEA (73.9 mg, 0.572 mmol). The reaction mixture was stirred at room temperature overnight. 4-(azetidin-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (90.0 mg, 0.286 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 2 hours. After the reaction mixture was cooled to room temperature, it was added to water (10.0 mL) and extracted with EA (15.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL×2), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (60.96 mg, yield 42.9%, white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 497.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.19-9.16(m,1H),8.67-8.65(m,1H),8.63(s,1H),8.47(s,1H),8.37–8.35(m,1H),8.16(s,1H),7.92–7.88(m,2H),7.87– 7.84(m,2H),7.15(t,J＝5.9Hz,1H),4.38–4.31(m,3H),4.27(d,J＝5.9Hz,2H),4.22–4.17(m,2H),3.89(s,3H).

Example 16: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)pyrrolidine-1-carboxamide (Compound 16)

Step 1: Synthesis of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Potassium carbonate (297 mg, 2.15 mmol) and Pd(dppf)Cl 2 DCM complex (46.3 mg, 0.054 mmol) were added to a mixed solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin- ₄ -yl trifluoromethanesulfonate (400 mg, 1.07 mmol) and tert-butyl 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (349 mg, 1.18 mmol) in water (1.00 mL) and 1,4-dioxane (4.00 mL). Under argon protection, the reaction mixture was stirred at 90°C for 4 hours. The reaction mixture was cooled to room temperature and poured into water (10.0 mL), and extracted with EA (15.0 mL×3). The combined organic phases were washed with saturated brine (15.0 mL x 3), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product. The target compound (300 mg, yield 71.3%, light yellow solid) was obtained by column chromatography separation and purification (PE:EA=1:1-1:3). LC-MS (ESI) m/z 413.1 [M+Na] ⁺ .

Step 2: Synthesis of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)pyrrolidine-1-carboxylate

Palladium on carbon (100 mg) was added to a solution of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (300 mg, 0.768 mmol) in EA (8.00 mL). The reaction mixture was stirred at 40°C for 24 hours under a hydrogen atmosphere. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure to give the target compound (250 mg, yield 82.9%, light yellow solid). LC-MS (ESI) m/z 293.1 [M-100+H] ⁺ .

Step 3: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(pyrrolidin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)pyrrolidine-1-carboxylate (250 mg, 0.637 mmol) in methanolic hydrogen chloride (3.0 M, 6.00 mL) was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure to give the target compound (200 mg, yield 95.5%, white solid). LC-MS (ESI) m/z 293.3 [M+H] ⁺ .

Step 4: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)pyrrolidine-1-carboxamide

To a solution of CDI (91.3 mg, 0.563 mmol) in DMF (2.00 mL) at room temperature, 2-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (100 mg, 0.520 mmol) and DIEA (112 mg, 0.867 mmol) were added. The reaction mixture was stirred at room temperature for 16 hours. 6-(1-methyl-1H-pyrazol-4-yl)-4-(pyrrolidin-3-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (142 mg, 0.443 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 3 hours. The reaction mixture was poured into water (10.0 mL) and extracted with EA (15.0 mL×2). The combined organic phases were washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product. The title compound (23.3 mg, yield 10.6%, white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid) and chiral column purification. LC-MS (ESI) m/z 511.2 [M+H] ⁺ . ¹ H NMR (400 MHz, MeOH-d ₄ ) δ 8.87 (d, J = 1.3 Hz, 1H), 8.48 (dd, J = 4.5, 0.8 Hz, 1H), 8.40 (s, 1H), 8.37-8.35 (m, 1H), 8.06 (s, 1H), 7.90 (d, J = 0.7 Hz, 1H), 7.88-7.81 (m, 2H), 7.69-7.66 (m, 1H), 7. 57(s,1H),7.06–6.99(m,1H),4.49–4.37(m,2H),4.17–4.10(m,1H),3.96–3.88(m,4H),3.84–3.76(m,1H),3.62–3.53(m,2H),2.58–2.50(m,1H), 2.38–2.30(m,1H).

Example 17: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 17)

Step 1: Synthesis of 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (220 mg, 0.512 mmol) in methanolic hydrogen chloride (3.0 M, 8.00 mL) was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure to give the target compound (180 mg, crude product, gray solid). LC-MS (ESI) m/z 291.2 [M+H] ⁺ .

Step 2: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide

At room temperature, (6-methoxypyridin-3-yl)methylamine (45.7 mg, 0.330 mmol) and DIEA (71.2 mg, 0.550 mmol) were added to a solution of CDI (58.1 mg, 0.358 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 16 hours. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (90.0 mg, 0.275 mmol) was added to the reaction mixture. The reaction mixture was stirred at 50°C for 3 hours. After the reaction mixture was cooled to room temperature, it was poured into water (10.0 mL) and extracted with EA (15.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL×2), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a crude product. The target compound (7.52 mg, two-step yield 6.01%, white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 455.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.24(d,J＝1.3Hz,1H),8.68(s,1H),8.38(s,1H),8.11(s,1H),8.10(d,J＝2.0Hz,1H),7.88(d,J＝1.2Hz,1H),7.69–7.65(m,1H),6 .92–6.88(m,1H),6.78(d,J＝8.4Hz,1H),6.37–6.35(m,1H),4.62–4.58(m,2H),4.36–4.32(m,2H),4.23(d,J＝5.7Hz,2H),3.88(s,3H),3.83(s,3H).

Example 18: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 18)

Step 1: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide

At room temperature, 1-(6-methoxypyridin-3-yl)ethan-1-amine (50.3 mg, 0.330 mmol) and DIEA (71.2 mg, 0.550 mmol) were added to a solution of CDI (58.1 mg, 0.358 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 16 hours. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (90.0 mg, 0.275 mmol) was added to the reaction mixture. The reaction mixture was stirred at 50°C for 3 hours. After the reaction mixture was cooled to room temperature, it was poured into water (10.0 mL) and extracted with EA (15.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (50.88 mg, yield 39.4%, white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 469.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ9.24(d,J＝1.3Hz,1H),8.68(s,1H),8.38(s,1H),8.14(d,J＝2.4Hz,1H),8.12(s,1H),7.88(d,J＝1.2Hz,1H),7.75–7.71(m,1H),6.78(d,J＝8.6Hz,1H), 6.61(d,J＝8.0Hz,1H),6.37–6.34(m,1H),4.91–4.86(m,1H),4.62–4.57(m,2H),4.38–4.33(m,2H),3.88(s,3H),3.82(s,3H),1.42(d,J＝7.1Hz,3H).

Example 19: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 19) and its hydrochloride (Compound 19-1)

Step 1: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide and its hydrochloride

To a solution of CDI (71.0 mg, 0.438 mmol) in DMF (4.00 mL) at 0°C, 1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethan-1-amine (83.3 mg, 0.404 mmol) and DIEA (87.0 mg, 0.674 mmol) were added. The reaction mixture was stirred at room temperature overnight. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (110 mg, 0.337 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 2 hours. After the reaction mixture was cooled to room temperature, water (10.0 mL) was added and extracted with EA (10.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 19) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound ( Compound 19-1) in the form of hydrochloride (54.1 mg, two-step yield 38.7%, white solid). LC-MS (ESI) m/z 523.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.25 (s, 1H), 8.71–8.64 (m, 2H), 8.47 (d, J = 1.9Hz, 1H), 8.39 (s, 1H), 8.13 (s, 1H), 8.04–7.99 (m, 1H), 7.93–7.86 (m, 3H), 6.7 7(d,J＝7.7Hz,1H),6.38(s,1H),5.03–4.96(m,1H),4.63(s,2H),4.44–4.34(m,2H),3.89(s,3H),1.49(d,J＝7.1Hz,3H).

Example 20: Synthesis of 3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 20)

Step 1: Synthesis of tert-butyl 3-(3-cyano-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Potassium acetate (1.11 g, 11.3 mmol) and Pd(dppf)Cl 2 DCM complex (244 mg, 0.283 mmol) were added to a solution of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole- ₁ -carboxylate (2.20 g, 5.65 mmol) and pinacol diboron (7.17 g, 28.2 mmol) in anhydrous 1,4-dioxane (30.0 mL). Under nitrogen protection, the reaction mixture was stirred at 90°C overnight. The reaction solution was cooled to room temperature and poured into EA (30.0 mL). The solution was filtered through diatomaceous earth and the filter cake was washed with EA (20.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (12.2 g, crude product, black solid).

Step 2: Synthesis of tert-butyl 3-(3-cyano-6-hydroxypyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

At 0°C, sodium hydroxide (4.47 g, 112 mmol) was added to a solution of tert-butyl 3-(3-cyano-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (12.2 g, 28.0 mmol) in tetrahydrofuran (300 mL), and 30% aqueous hydrogen peroxide solution (22.8 mL, 224 mmol) was slowly added dropwise. The reaction mixture was stirred at room temperature for 2 hours. Saturated aqueous ammonium chloride solution (150 mL) was added to the reaction mixture, and then stirred at room temperature for 15 minutes. The organic phase was separated, and the aqueous phase was extracted with EA (100 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.20 g, two-step yield 65.1%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=5:1-1:1). LC-MS (ESI) m/z 227.0 [M-100+H] ⁺ .

Step 3: Synthesis of tert-butyl 3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

To a solution of tert-butyl 3-(3-cyano-6-hydroxypyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (400 mg, 1.23 mmol) in tetrahydrofuran (5.00 mL) was added aqueous sodium hydroxide solution (2.0 N, 1.23 mL, 2.46 mmol). The reaction mixture was stirred at room temperature for 15 minutes and then 2,2-dimethyloxirane (1.10 mL, 12.3 mmol) was added. After sealing the tube, the reaction mixture was stirred at 80°C for 16 hours. The reaction solution was cooled to room temperature and concentrated under reduced pressure to obtain a crude product. The target compound (350 mg, yield 71.7%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS(ESI)m/z 399.1[M+H] ⁺ .

Step 4: Synthesis of 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylic acid tert-butyl ester (250 mg, 0.627 mmol) was added to a methanol solution of hydrogen chloride (3.0 M, 10.0 mL). The reaction mixture was stirred at room temperature overnight. The mixture was concentrated under reduced pressure to give the target compound (200 mg, yield 95.2%, white solid). LC-MS (ESI) m/z 299.1 [M+H] ⁺ .

Step 5: Synthesis of 3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide

To a solution of CDI (63.0 mg, 0.389 mmol) in DMF (3.00 mL) were added (6-methoxypyridin-3-yl)methylamine (49.5 mg, 0.358 mmol) and DIEA (77.2 mg, 0.597 mmol). The reaction mixture was stirred at room temperature for 16 hours. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (100 mg, 0.299 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 3 hours. The reaction mixture was cooled to room temperature and added to water (10.0 mL). Extracted with EA (15.0 mL × 2). The combined organic phases were washed with saturated brine (10.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (67.0 mg, yield 48.5%, white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 463.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.67 (d, J = 2.0Hz, 1H), 8.61 (s, 1H), 8.09 (d, J = 2.0Hz, 1H), 7.66 (dd, J = 8.5, 2.4Hz, 1H), 7.41 (d, J = 1.8Hz, 1H), 6.88 (t, J = 5.8Hz, 1H) ,6.77(d,J＝8.5Hz,1H),6.37(s,1H),4.70(s,1H),4.55–4.49(m,2H),4.35 –4.29(m,2H),4.22(d,J＝5.7Hz,2H),3.85(s,2H),3.82(s,3H),1.21(s,6H) .

Example 21: Synthesis of 3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 21) and its hydrochloride (Compound 21-1)

Step 1: Synthesis of 3-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide and its hydrochloride To a solution of CDI (63.0 mg, 0.389 mmol) in DMF (3.00 mL) were added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methanamine (68.9 mg, 0.358 mmol) and DIEA (77.2 mg, 0.597 mmol). After the reaction mixture was stirred at room temperature for 16 hours, 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (100 mg, 0.299 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 3 hours. After the reaction mixture was cooled to room temperature, water (10.0 mL) was added and extracted with EA (15.0 mL×2). The combined organic phases were washed with saturated brine (10.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 21) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 21-1) in the form of hydrochloride (50.3 mg, yield 30.4%, white solid). LC-MS (ESI) m/z 517.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.69–8.66(m,2H),8.61(s,1H),8.41(d,J＝1.6Hz,1H),7.96–7.90(m,2H),7.90–7.86(m,1H),7.42(d,J＝1.9Hz,1H),7.02(t, J＝5.9Hz,1H),6.40–6.37(m,1H),4.69(s,1H),4.58–4.53(m,2H),4.38–4.32(m,4H),3.85(s,2H),1.21(s,6H).

Example 22: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide ( Compound 22)

Step 1: Synthesis of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Potassium acetate (159 mg, 1.62 mmol) and Pd(dppf)Cl 2 DCM complex (34.9 mg, 0.041 mmol) were added to a mixed solution of 6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (300 mg, 0.811 mmol) and tert-butyl 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (227 mg, 0.770 mmol) in water (1.00 mL) and tetrahydrofuran (5.00 mL). Under argon protection, the reaction mixture was stirred at 30°C for 8 hours. The reaction solution was poured into EA (80.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (250 mg, yield 79.2%, white solid) was obtained by column chromatography separation and purification (PE:EA=100:1-9:1). LC-MS (ESI) m/z 411.0, 413.0 [M+Na] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ8.67 (s, 1H), 8.27 (s, 1H), 7.36 (s, 1H), 6.37 (s, 1H), 4.57-4.43 (m, 4H), 1.51 (s, 9H).

Step 2: Synthesis of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Sodium carbonate (136 mg, 1.28 mmol) and Pd(dppf)Cl 2 DCM complex (27.7 mg, 0.032 mmol) were added to a solution of tert-butyl 3-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (250 mg, 0.642 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)-1H-pyrazole (147 mg, 0.706 mmol) in water (1.00 mL) and 1,4-dioxane (5.00 mL). Under argon protection, the reaction mixture was stirred at 100°C for 6 hours. The reaction mixture was cooled to room temperature and poured into EA (80.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (160 mg, yield 63.8%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:2). LC-MS (ESI) m/z 413.1 [M+Na] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ9.23 (s, 1H), 8.67 (s, 1H), 8.39 (d, J=4.1 Hz, 1H), 8.12 (s, 1H), 7.89 (s, 1H), 6.31 (s, 1H), 4.62–4.54 (m, 2H), 4.35–4.27 (m, 2H), 3.88 (s, 3H), 1.46 (s, 9H).

Step 3: Synthesis of 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (160 mg, 0.410 mmol) in methanolic hydrogen chloride (3.0 M, 6.00 mL) was stirred at room temperature for 16 hours. The reaction mixture was decompressed to give the target compound (130 mg, yield 97.1%, off-white solid). LC-MS (ESI) m/z 291.2 [M+H] ⁺ .

Step 4: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-2,5-dihydro-1H-pyrrole-1-carboxamide

To a solution of CDI (83.8 mg, 0.517 mmol) in DMF (3.00 mL) at room temperature, (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (91.7 mg, 0.477 mmol) and DIEA (103 mg, 0.796 mmol) were added. The reaction mixture was stirred at room temperature for 16 hours. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (130 mg, 0.398 mmol) was added to the reaction mixture. The reaction mixture was stirred at 50°C for 3 hours. The reaction mixture was poured into water (20.0 mL) and extracted with EA (40.0 mL×2). The combined organic phases were washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (66.4 mg, yield 30.1%, yellow solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 509.3 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.25–9.23(m,1H),8.70–8.66(m,2H),8.42–8.40(m,1H),8.38(s,1H),8.12(s,1H),7.96–7.93(m,1H),7.92–7.87(m,3H), 7.07–7.03(m,1H),6.39–6.36(m,1H),4.65–4.60(m,2H),4.39–4.34(m,4H),3.88(s,3H).

Example 23: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperidine-1-carboxamide (Compound 23) and its hydrochloride ( Compound 23-1)

Step 1: Synthesis of 1-amino-3-bromo-5-methoxypyridine-2,4,6-trimethylbenzenesulfonate

A solution of 3-bromo-5-methoxypyridine (5.00 g, 26.6 mmol) and O-2,4,6-trimethylbenzenesulfonylhydroxylamine (8.59 g, 39.9 mmol) in DCM (75.0 mL) was stirred at 0°C for 1 hour. PE (75.0 mL) was slowly added to the reaction solution at 0°C and stirred for 15 minutes to obtain a white suspension. The suspension was filtered to obtain a white solid. The solid was dried to obtain the target compound (10.2 g, yield 95.1%, off-white solid). LC-MS (ESI) m/z 202.9, 204.9 [M] ⁺ . ¹ HNMR (400MHz, DMSO-d ₆ ) δ8.62–8.59(m,1H),8.58–8.35(m,3H),8.16–8.13(m,1H),6.64(s,2H),3.86(s,3H),2.39(s,6H),2.06(s,3H).

Step 2: Synthesis of 6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile

At 0°C, acrylonitrile (3.09 g, 58.2 mmol) and DIEA (5.44 mL, 32.9 mmol) were added to a solution of 1-amino-3-bromo-5-methoxypyridine-2,4,6-trimethylbenzenesulfonate (10.2 g, 25.3 mmol) in 1,4-dioxane (100 mL). After the reaction solution was stirred at 0°C for 2 hours, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (12.1 g, 53.1 mmol) was added. After the reaction solution was stirred at room temperature for 1 hour, the temperature was raised to room temperature and continued to stir for 16 hours. The reaction mixture was poured into ice water (100 mL) to obtain a brown suspension. The suspension was filtered and the filter cake was washed with water (50.0 mL) to obtain an off-white solid. The target compound (2.60 g, yield 40.8%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=100:1-9:1). LC-MS(ESI)m/z 252.0,254.0[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.95–8.91 (m, 1H), 8.60–8.56 (m, 1H), 7.24–7.22 (m, 1H), 4.03 (s, 3H).

Step 3: Synthesis of 6-bromo-4-hydroxypyrazolo[1,5-a]pyridine-3-carbonitrile

Under argon protection, anhydrous aluminum chloride (2.38 g, 17.9 mmol) was added to a solution of 6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carbonitrile (1.50 g, 5.95 mmol) in 1,2-dichloroethane (25.0 mL). The reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature, and dilute hydrochloric acid (1.0 M, 15.0 mL) and water (30.0 mL) were added. Extraction was performed with EA (120 mL × 3). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (900 mg, yield 63.5%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=5:1-3:1). LC-MS (ESI) m/z 239.1 [M+H] ⁺ .

Step 4: Synthesis of 6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate

To a solution of 6-bromo-4-hydroxypyrazolo[1,5-a]pyridine-3-carbonitrile (900 mg, 3.78 mmol) and 1,1,1-trifluoro-N-phenyl-N-((trifluoromethyl)sulfonyl)methanesulfonamide (1.62 g, 4.54 mmol) in N,N-dimethylacetamide (8.00 mL) was added DIEA (1.25 mL, 7.56 mmol). The reaction mixture was stirred at room temperature for 16 hours. 1,1,1-trifluoro-N-phenyl-N-((trifluoromethyl)sulfonyl)methanesulfonamide (1.35 g, 3.78 mmol) and DIEA (0.625 mL, 3.78 mmol) were added. The reaction mixture was stirred at room temperature for another 3 hours. The reaction mixture was poured into water (25.0 mL) and extracted with EA (80.0 mL). The organic phase was washed with saturated brine (20.0 mL × 3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.30 g, yield 92.9%, yellow solid) was obtained by column chromatography separation and purification (PE: EA = 12: 1). LC-MS (ESI) m/z 367.9, 369.9 [MH] ^- .

Step 5: Synthesis of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate

Potassium acetate (424 mg, 4.32 mmol) and Pd(dppf)Cl 2 DCM complex (140 mg, 0.162 mmol) were added to a mixed solution of 6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (800 mg, 2.16 mmol) and tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate (668 mg, 2.16 mmol) in water (1.50 mL) and tetrahydrofuran (7.50 mL). The _argon atmosphere was replaced three times, and the reaction mixture was stirred at 40°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (25.0 mL), and extracted with EA (60.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (590 mg, yield 67.5%, white solid) was obtained by column chromatography separation and purification (PE:EA=12:1-10:1). LC-MS (ESI) m/z 302.9, 304.9 [M-100+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 9.31 (d, J=1.6 Hz, 1H), 8.68 (s, 1H), 7.65 (d, J=1.5 Hz, 1H), 6.05 (s, 1H), 4.08–4.02 (m, 2H), 3.64–3.57 (m, 2H), 2.49–2.43 (m, 2H), 1.44 (s, 9H).

Step 6: Synthesis of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate

Sodium carbonate (105 mg, 0.992 mmol) and Pd(dppf)Cl 2 DCM complex (21.4 mg, 0.025 mmol) were added to a mixed solution of tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin- ₄ -yl)-3,6-dihydropyridine-1(2H)-carboxylate (200 mg, 0.496 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazole (124 mg, 0.595 mmol) in water (0.60 mL) and 1,4-dioxane (3.00 mL). The argon atmosphere was replaced three times, and the reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (20.0 mL), and extracted with EA (50.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (165 mg, yield 82.3%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 405.3 [M+H] ⁺ . ¹ HNMR (400MHz, DMSO-d ₆ ) δ9.19(d,J＝1.4Hz,1H),8.63(s,1H),8.38(s,1H),8.11(d,J＝0.6Hz,1H),7.75(d,J＝1.0Hz,1H),6.08–6.04(m,1H),4.10–4.05( m,2H),3.89(s,3H),3.67–3.62(m,2H),2.55–2.52(m,2H),1.46(s,9H).

Step 7: Synthesis of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-1-carboxylate

Platinum dioxide (185 mg, 0.816 mmol) was added to a solution of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate (165 mg, 0.408 mmol) in EA (10.0 mL). The mixture was replaced with hydrogen three times. The reaction mixture was stirred at room temperature for 24 hours. The reaction mixture was filtered through diatomaceous earth and the filter cake was washed with EA (10.0 mL). The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (50.0 mg, yield 30.1%, white solid) was purified by reverse phase preparation (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 307.4 [M-100+H] ⁺ .

Step 8: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(piperidin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)piperidine-1-carboxylate (50.0 mg, 0.123 mmol) in methanolic hydrogen chloride (3.0 M, 5.00 mL) was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (42.0 mg, yield 99.5%, light yellow solid). LC-MS (ESI) m/z 307.1 [M+H] ⁺ .

Step 9: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)piperidine-1-carboxamide hydrochloride

To a mixture of sodium bicarbonate aqueous solution (2.50 mL) and DCM (5.00 mL) were added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (19.6 mg, 0.102 mmol) and triphosgene (18.2 mg, 0.061 mmol) in sequence. The reaction mixture was stirred at room temperature for 1 hour. Extracted with DCM (8.00 mL). The organic phase was washed with saturated brine (3.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (31.0 mg, 0.306 mmol) and 6-(1-methyl-1H-pyrazol-4-yl)-4-(piperidin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (42.0 mg, 0.123 mmol) were added to the filtrate in sequence. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was poured into water (20.0 mL) and extracted with DCM (30.0 mL×3). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product (Compound 23). The target compound (Compound 23-1) (16.0 mg, yield 23.2%, light yellow solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) in the form of hydrochloride. LC-MS (ESI) m/z 525.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.14–9.11(m,1H),8.67(d,J＝4.4Hz,1H),8.63(s,1H),8.42(s,1H),8.39–8.36(m,1H),8.11(s,1H),7.93–7.86(m,3H),7.67( s,1H),7.34–7.26(m,1H),4.34–4.30(s,2H),4.25(d,J＝13.0Hz,2H),3.88(s,3H),3.43–3.33(m,1H),2.91–2.82(m,2H),2.00–1.92(m,2H),1.80–1. 68(m,2H).

Example 24: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-dihydropyridine-1(2H)-carboxamide (Compound 24 )

Step 1: Synthesis of tert-butyl 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate

Tert-butyl 4-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate (400 mg, 0.992 mmol), 2,2-dimethyloxirane (715 mg, 9.92 mmol), cesium carbonate (970 mg, 2.98 mmol), 2-di-tert-butylphosphino-3,4,5,6-tetramethyl-2',4',6'-triisopropylbiphenyl (76.3 mg, 0.159 mmol) and tris(dibenzylideneacetone)dipalladium (36.3 mg, 0.0397 mmol) were added to a mixed solvent of water (2.00 mL) and 1,4-dioxane (6.00 mL). Under argon protection, the reaction mixture was stirred at 100 ° C for 16 hours. The reaction mixture was cooled to room temperature, the organic phase was separated, and concentrated under reduced pressure to obtain a crude product. The title compound (65.0 mg, yield 30.0%, off-white solid) was obtained by column chromatography separation and purification (PE:EA=55:45). LC-MS (ESI) m/z 313.2 [M-100+H] ⁺ . ¹ H NMR (400 MHz, CDCl ₃ ) δ8.17 (s, 1H), 8.09 (d, J=2.1 Hz, 1H), 7.05 (d, J=1.8 Hz, 1H), 6.01–5.97 (m, 1H), 4.19–4.14 (m, 2H), 3.83 (s, 2H), 3.77 (t, J=5.6 Hz, 2H), 2.54-2.45 (m, 2H), 1.50 (s, 9H), 1.38 (s, 6H).

Step 2: Synthesis of 6-(2-hydroxy-2-methylpropoxy)-4-(1,2,3,6-tetrahydropyridin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

At room temperature, tert-butyl 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate (65.0 mg, 0.158 mmol) and 3.0 M methanol solution of hydrogen chloride (1.00 mL) were added to methanol (1.00 mL). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (50.0 mg, yield 90.9%, off-white solid). LC-MS (ESI) m/z 313.2 [M+H] ⁺ .

Step 3: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-dihydropyridine-1(2H)-carboxamide

To a mixture of sodium bicarbonate aqueous solution (2.50 mL) and DCM (5.00 mL) was added (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (60.6 mg, 0.315 mmol). After stirring for 15 minutes, triphosgene (56.1 mg, 0.189 mmol) was added. The reaction mixture was stirred at room temperature for 2 hours. DCM (5.00 mL) and water (2.50 mL) were added. The organic phase was separated and washed with water (5.00 mL) and saturated brine (5.00 mL), dried over anhydrous sodium sulfate, and filtered.

TEA (63.7 mg, 0.630 mmol) and 6-(2-hydroxy-2-methylpropoxy)-4-(1,2,3,6-tetrahydropyridin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (50.0 mg, 0.143 mmol) were added to the above filtrate in sequence. The reaction mixture was stirred at room temperature for half an hour. Water (15.0 mL) was added and extracted with DCM (20.0 mL×2). The combined organic phases were washed with water (15.0 mL) and saturated brine (15.0 mL), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (11.8 mg, yield 14.0%, off-white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 531.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.67(d,J＝3.2Hz,1H),8.61(s,1H),8.55(s,1H),8.38(s,1H),7.95–7.85(m,3H),7.34–7.21(m,2H),6.09–6.03(m,1H),4.7 4–4.65(m,1H),4.33(d,J=4.4Hz,2H),4.06(s,2H),3.83(s,2H),3.69–3.59(m,2H),2.55–2.50(m,2H),1.21(s,6H).

Example 25: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-dihydropyridine-1(2H)-carboxamide (Compound 25 )

Step 1: Synthesis of tert-butyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylate

Potassium acetate (42.3 mg, 0.431 mmol) and Pd(dppf)Cl 2 DCM complex (13.9 mg, 0.016 mmol) were added to a mixed solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (80.0 mg, 0.215 mmol) and tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,6-dihydropyridine-1(2H)-carboxylate (66.6 mg, 0.215 mmol) in water (0.300 mL) and tetrahydrofuran (1.50 mL). The argon atmosphere was replaced three times, and the reaction mixture was stirred at 50 _° C for 4 hours. The reaction mixture was cooled to room temperature and allowed to stand for separation. The organic phase was concentrated under reduced pressure to obtain a crude product. The target compound (60 mg, yield 68.8%, light yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 405.1 [M+H] ⁺ .

Step 2: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1,2,3,6-tetrahydropyridin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-3,6-dihydropyridine-1(2H)-carboxylic acid tert-butyl ester (60.0 mg, 0.148 mmol) was added to a methanol solution of hydrogen chloride (3.0 M, 5.00 mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (48.0 mg, yield 94.9%, light yellow solid). LC-MS (ESI) m/z 305.2 [M+H] ⁺ .

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3,6-dihydropyridine-1(2H)-carboxamide

Triphosgene (20.9 mg, 0.070 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (22.6 mg, 0.117 mmol) in aqueous sodium bicarbonate (2.50 mL) and DCM (5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. It was extracted with DCM (10.0 mL). The organic phase was washed with saturated brine (4.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (35.6 mg, 0.352 mmol) and 6-(1-methyl-1H-pyrazol-4-yl)-4-(1,2,3,6-tetrahydropyridin-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (48.0 mg, 0.141 mmol) were added to the filtrate. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was poured into water (10.0 mL) and extracted with DCM (30.0 mL × 3). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (28.2 mg, yield 46.1%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 523.3 [M+H] ⁺ . ¹ HNMR (400MHz, DMSO-d ₆ ) δ9.20–9.17(m,1H),8.68(d,J＝4.4Hz,1H),8.63(s,1H),8.40–8.38(m,1H),8.37(s,1H),8.10(s,1H),7.94–7.86(m,3H),7.75– 7.72(m,1H),7.28(t,J＝5.4Hz,1H),6.10–6.06(m,1H),4.34(d,J＝5.4Hz,2H),4.12–4.06(m,2H),3.88(s,3H),3.70–3.64(m,2H),2.56–2.53(m,2H).

Example 26: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)cyclohexanamide (Compound 26)

Step 1: Synthesis of methyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohex-3-ene-1-carboxylate

Potassium acetate (52.9 mg, 0.538 mmol) and Pd(dppf)Cl 2 DCM complex (17.4 mg, 0.020 mmol) were added to a mixed solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (100 mg, 0.269 mmol) and methyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)cyclohex- ₃ -ene-1-carboxylate (72.2 mg, 0.269 mmol) in water (0.500 mL) and tetrahydrofuran (2.50 mL). The argon gas was replaced 3 times. The reaction mixture was stirred at 50°C for 5 hours. The reaction solution was cooled to room temperature and the organic phase was separated. The crude product was obtained by concentration under reduced pressure. The target compound (90.0 mg, yield 92.5%, light yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 362.0 [M+H] ⁺ .

Step 2: Synthesis of methyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohexane-1-carboxylate

At room temperature, 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohex-3-ene-1-carboxylic acid methyl ester (90.0 mg, 0.249 mmol) was added to a mixed solvent of methanol (15.0 mL) and EA (15.0 mL). Palladium carbon (30.0 mg) was added. Under a hydrogen atmosphere, the reaction mixture was stirred at room temperature for 32 hours. The reaction mixture was filtered through diatomaceous earth, and the filter cake was washed with EA (20.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (50.0 mg, yield 55.2%, white solid). LC-MS (ESI) m/z 364.3 [M+H] ⁺ .

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohexane-1-carboxylic acid

To a mixed solution of methyl 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohexane-1-carboxylate (50.0 mg, 0.138 mmol) in water (0.500 mL), tetrahydrofuran (1.00 mL) and methanol (2.00 mL) was added lithium hydroxide monohydrate (8.66 mg, 0.206 mmol). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to remove the organic solvent and then added to water (10.0 mL). The pH was adjusted to 4 with 1.0 M hydrochloric acid solution. The mixed solution was extracted with EA (20.0 mL×3). The organic phases were combined, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (12.0 mg, yield 25.0%, white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid). LC-MS(ESI)m/z 350.4[M+H] ⁺ .

Step 4: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)cyclohexanamide

To a solution of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)cyclohexane-1-carboxylic acid (12.0 mg, 0.034 mmol) in DMF (0.500 mL) at room temperature were added 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (9.97 mg, 0.052 mmol), HOBt (7.03 mg, 0.052 mmol), DIEA (8.88 mg, 0.069 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methanamine (6.59 mg, 0.034 mmol). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was poured into water (10.0 mL) and extracted with EA (30.0 mL). The organic phase was washed with saturated brine (5.00 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (4.46 mg, yield 25.1%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 524.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.10(d,J=0.8Hz,1H),8.65–8.62(m,1H),8.61(s,1H),8.46-8.41(m,1H),8.40(s,1H),8.38–8.35(m,1H),8.07(s,1H),7.92– 7.86(m,3H),7.49(s,1H),4.39–4.34(m,2H),3.87(s,3H),2.69–2.63(m,2H),2.19–2.13(m,2H),1.92–1.85(m,4H),1.79–1.71(m,2H).

Example 27: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 27)

Step 1: Synthesis of 6-bromo-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

Potassium acetate (451 mg, 4.60 mmol) and Pd(dppf)Cl 2 DCM complex (149 mg, 0.173 mmol) were added to a mixed solution of 6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (850 mg, 2.30 mmol) and 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- _2- yl)-1H-pyrazole (607 mg, 2.18 mmol) in water (2.00 mL) and tetrahydrofuran (10.0 mL). Under argon protection, the reaction mixture was stirred at 40°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (40.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (550 mg, yield 64.3%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=10:1-5:1). LC-MS (ESI) m/z 371.9, 373.9 [M+H] ⁺ . ¹ HNMR (400 MHz, CDCl ₃ ) δ8.67–8.65 (m, 1H), 8.27 (s, 1H), 8.11 (s, 1H), 7.84 (s, 1H), 7.48–7.46 (m, 1H), 5.53–5.48 (m, 1H), 3.81–3.70 (m, 2H), 2.21–2.16 (m, 2H), 1.75–1.70 (m, 2H), 1.68–1.62 (m, 2H).

Step 2: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

To a mixed solution of 6-bromo-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (550 mg, 1.48 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (369 mg, 1.77 mmol) in water (2.00 mL) and 1,4-dioxane (10.0 mL) were added sodium carbonate (314 mg, 2.96 mmol) and Pd(dppf)Cl ₂ DCM complex (63.8 mg, 0.074 mmol). Under argon protection, the reaction mixture was stirred at 80°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (30.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (320 mg, yield 58.0%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:2). LC-MS (ESI) m/z 374.0 [M+H] ⁺ .

Step 3: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile trifluoroacetate

6-(1-methyl-1H-pyrazol-4-yl)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (320 mg, 0.857 mmol) and trifluoroacetic acid (0.500 mL) were added to DCM (15.0 mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to give the target compound (330 mg, yield 95.4%, yellow solid). LC-MS (ESI) m/z 290.1 [M+H] ⁺ .

Step 4: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

Triphosgene (29.4 mg, 0.099 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (31.7 mg, 0.165 mmol) in saturated sodium bicarbonate aqueous solution (3.00 mL) and DCM (5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. It was extracted with DCM (10.0 mL). The organic phase was washed with saturated brine (4.00 mL×3), dried over anhydrous sodium sulfate, and filtered. TEA (50.2 mg, 0.496 mmol) and 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile trifluoroacetate (80.0 mg, 0.198 mmol) were added to the filtrate. The reaction mixture was stirred at room temperature for 20 minutes. The reaction solution was diluted with water (15.0 mL) and extracted with DCM (3.00 mL × 2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (4.10 mg, yield 4.08%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 508.4 [M+H] ⁺ . ¹ HNMR (400MHz, DMSO-d ₆ ) δ9.45–9.41(m,1H),9.27(s,1H),8.81(s,1H),8.71–8.67(m,2H),8.49–8.46(m,1H),8.39(s,1H),8.26(s,1H),8.13(s,1H) ,8.03–7.96(m,2H),7.95–7.90(m,2H),4.55(d,J＝5.7Hz,2H),3.89(s,3H).

Example 28: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 28) and its hydrochloride (Compound 28-1 )

Step 1: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

Sodium carbonate (457 mg, 4.31 mmol) and Pd(dppf)Cl 2 DCM complex (92.8 mg, 0.108 mmol) were added to a mixed solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (800 mg, 2.15 mmol) and 1-(tetrahydro-2H-pyran-2-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)-1H-pyrazole (659 mg, 2.37 mmol) in water (1.20 mL) and tetrahydrofuran (6.00 mL). Under argon protection, the reaction mixture was stirred at 60°C for 5 hours. The reaction mixture was cooled to room temperature and poured into EA (60.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (700 mg, yield 87.0%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:5). LC-MS (ESI) m/z 396.1 [M+Na] ⁺ .

Step 2: Synthesis of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

A solution of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (700 mg, 1.87 mmol) in methanolic hydrogen chloride (3.0 M, 10.0 mL) was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to give the target compound (600 mg, yield 98.2%, yellow solid). LC-MS (ESI) m/z 290.3 [M+H] ⁺ .

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide and its hydrochloride

At room temperature, (6-methoxypyridin-3-yl)methylamine (46.7 mg, 0.338 mmol) and DIEA (79.4 mg, 0.614 mmol) were added to a solution of CDI (64.7 mg, 0.399 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 16 hours. 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (100 mg, 0.307 mmol) was added to the reaction mixture. The reaction mixture was stirred at 70°C for 8 hours. After the reaction mixture was cooled to room temperature, it was poured into water (15.0 mL) and extracted with EA (100 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 28) . The target compound (Compound 28-1) was obtained as a hydrochloride salt (19.6 mg, yield 13.0%, yellow solid) by purification using preparation (acetonitrile/water containing 0.05% hydrochloric acid). LC-MS (ESI) m/z 454.0 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.33–9.28(m,1H),9.27–9.25(m,1H),8.80–8.78(m,1H),8.68(s,1H),8.39(s,1H),8.25–8.23(m,1H),8.19–8.16(m,1H), 8.13(s,1H),7.98–7.95(m,1H),7.77–7.73(m,1H),6.83(d,J＝8.5Hz,1H),4.42(d,J＝6.2Hz,2H),3.89(s,3H),3.84(s,3H).

Example 29: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 29)

Step 1: Synthesis of 1-(6-methoxypyridin-3-yl)ethan-1-one oxime

To a solution of 1-(6-methoxypyridin-3-yl)ethane-1-one (1.00 g, 6.62 mmol) in ethanol (10.0 mL) was added a solution of hydroxylamine hydrochloride (919 mg, 13.2 mmol) and sodium acetate (1.09 g, 13.2 mmol) in water (5.00 mL). The reaction mixture was stirred at 90°C for 2 hours. The solid residue obtained after the reaction solution was concentrated under reduced pressure was added to water (30.0 mL). Filtered, the filter cake was washed with water (30.0 mL). The filter cake was vacuum dried to obtain the target product (1.05 g, yield 95.5%, white solid). LC-MS (ESI) m/z 167.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ11.20(s,1H),8.42–8.39(m,1H),8.00–7.95(m,1H),6.85–6.82(m,1H),3.87(s,3H),2.14(s,3H).

Step 2: Synthesis of 1-(6-methoxypyridin-3-yl)ethan-1-amine

At -10 ° C, nickel chloride hexahydrate (3.00 g, 12.6 mmol) was added to a methanol solution (20.0 mL) of 1-(6-methoxypyridin-3-yl)ethan-1-one oxime (1.05 g, 6.32 mmol), and then sodium borohydride (1.91 g, 50.5 mmol) was slowly added. The reaction mixture was stirred at room temperature for 3 hours. Acetone (10.0 mL) was added to the reaction mixture to quench the reaction. Filtered through diatomaceous earth and washed with EA (100 mL) to obtain a black filtrate. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (350 mg, yield 36.4%, yellow oil) was obtained by column chromatography separation and purification (DCM: methanol = 100: 1-10: 1). ¹ HNMR (400MHz, DMSO-d ₆ ) δ8.15–8.10(m,1H),7.77–7.72(m,1H),6.78(d,J＝8.5Hz,1H),4.11–4.00(m,1H),3.82(s,3H),3.51(br s,2H),1.29(d,J＝6.5Hz, 3H).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

At room temperature, 1-(6-methoxypyridin-3-yl)ethyl-1-amine (51.4 mg, 0.338 mmol) and DIEA (79.3 mg, 0.614 mmol) were added to a DMF (2.00 mL) solution of CDI (74.7 mg, 0.460 mmol). The reaction mixture was stirred at room temperature for 16 hours and 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (100 mg, 0.307 mmol) was added. The reaction mixture was stirred at 70°C for 5 hours. The reaction mixture was cooled to room temperature and poured into water (20.0 mL) and extracted with EA (100 mL). After separation of the organic phase, it was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (37.5 mg, yield 26.1%, yellow solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 468.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.27–9.25(m,1H),9.14(d,J＝8.4Hz,1H),8.77(s,1H),8.68(s,1H),8.38(s,1H),8.25(s,1H),8.23–8.21(m,1H),8.12(s,1H) ,7.97–7.95(m,1H),7.87–7.83(m,1H),6.82(d,J＝8.6Hz,1H),5.10-5.03(m,1H),3.89(s,3H),3.83(s,3H),1.58(d,J＝7.1Hz,3H).

Example 30: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 30)

Step 1: Synthesis of (R,E)-N-(1-(6-methoxypyridin-3-yl)ethylidene)-2-methylpropyl-2-sulfenamide

To a solution of 1-(6-methoxypyridin-3-yl)ethan-1-one (1.25 g, 8.27 mmol) in 1,2-dichloroethane (12.0 mL) were added (R)-2-methylpropyl-2-sulfenamide (1.25 g, 10.3 mmol) and tetraethyl titanate (6.93 mL, 33.1 mmol). The reaction mixture was stirred in a sealed microwave tube at 110°C for 2 hours. The reaction mixture was cooled to room temperature. After being concentrated under reduced pressure to remove the organic solvent, it was dissolved in EA (100 mL) and water (20.0 mL) to obtain a suspension. Filter, and wash the filter cake with EA (30.0 mL). The filtrate was dried over anhydrous sodium sulfate and filtered. Concentrated under reduced pressure to obtain a crude product. Purified by column chromatography (PE:EA=10:1-4:1) to obtain the target compound (2.00 g, yield 95.2%, yellow oil). LC-MS(ESI)m/z 255.2[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.74 (d, J = 2.3 Hz, 1H), 8.21 ( dd, J = 8.8, 2.5 Hz, 1H), 6.93 ( d, J = 8.8 Hz, 1H), 3.93 ( s, 3H), 2.71 ( s, 3H), 1.21 ( s, 9H).

Step 2: Synthesis of (R)-N-((S)-1-(6-methoxypyridin-3-yl)ethyl)-2-methylpropyl-2-sulfenamide

At -70°C and under argon protection, lithium tri-sec-butylborohydride (1.0M THF solution, 8.65mL, 8.65mmol) was added dropwise to a solution of (R,E)-N-(1-(6-methoxypyridin-3-yl)ethylidene)-2-methylpropyl-2-sulfenamide (2.00g, 7.86mmol) in dry tetrahydrofuran (60.0mL). The reaction mixture was stirred at -70°C for 90 minutes. Saturated aqueous ammonium chloride solution (80.0mL) was added to the reaction solution. The organic phase was separated and the aqueous phase was extracted with EA (80.0mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.50g, yield 74.4%, colorless oil) was obtained by column chromatography separation and purification (DCM:MeOH=100:1-20:1). LC-MS(ESI)m/z257.1[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.10(d,J＝2.4Hz,1H),7.67(dd,J＝8.6,2.5Hz,1H),6.79(d,J＝8.6Hz,1H),5.38(d,J＝5.1Hz,1H),4.43–4.36(m,1H),3.83(s,3H) ,1.45(d,J＝6.7Hz,3H),1.09(s,9H).

Step 3: Synthesis of (S)-1-(6-methoxypyridin-3-yl)ethan-1-amine

At 0°C, a solution of 1,4-dioxane hydrochloride (4.0M, 15.0mL, 60.0mmol) was added dropwise to a solution of (R)-N-((S)-1-(6-methoxypyridin-3-yl)ethyl)-2-methylpropyl-2-sulfenamide (1.50g, 5.85mmol) in methanol (15.0mL). The reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was poured into a saturated aqueous sodium bicarbonate solution (100mL) and extracted with a mixed solvent (DCM:MeOH=10:1, 100mL×5). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (650mg, yield 73.0%, light yellow oil) was obtained by column chromatography separation and purification (DCM:MeOH=20:1-10:1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.09 (d, J = 2.4 Hz, 1H), 7.71 ( dd, J = 8.5, 2.5 Hz, 1H), 6.75 ( d, J = 8.5 Hz, 1H), 4.00–3.94 ( m, 1H), 3.81 ( s, 3H), 1.23 ( d, J = 6.6 Hz, 3H).

Step 4: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

At room temperature, (S)-1-(6-methoxypyridin-3-yl)ethan-1-amine (49.0 mg, 0.322 mmol) and DIEA (55.6 mg, 0.430 mmol) were added to a solution of CDI (69.7 mg, 0.430 mmol) in DMF (3.00 mL). The reaction mixture was stirred at room temperature for 2 hours, and then 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and diluted with EA (100 mL). Washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (32.0 mg, yield 31.9%, Ret. time = 1.861 min, ee 95.2%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). Chiral analysis method: Chiral column: Reprosil Chiral-OM 100*3mm 3μm; mobile phase: A: Supercritical CO ₂ , B: MeOH (0.1% DEA); gradient: A 60%, B 40% for 5min; flow rate: 1.5mL/min; column temperature: 35°C. LC-MS (ESI) m/z 468.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ )δ9.26(d,J＝1.4Hz,1H),9.14(d,J＝8.4Hz,1H),8.77(d,J＝0.7Hz,1H),8.68(s,1H),8.38(s,1H),8.25(d,J＝0.7Hz,1H),8.22(d,J＝2.4Hz,1H),8.12(d,J ＝0.6Hz,1H),7.96(d,J＝1.4Hz,1H),7.85(dd,J＝8.6,2.5Hz,1H),6.82(d,J＝8.6Hz,1H),5.12–5.02(m,1H),3.89(s,3H),3.83(s,3H),1.58(d,J＝7.1Hz,3 H).

Example 31: Synthesis of (R)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 31)

4-(3-Cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (50 mg dissolved in about 20 mL of methanol, injection volume 1.0 mL) was separated by Waters SFC 150 (room temperature, 100 bar, 214 nm) and 250*25 mm 10 μm Dr.maish Reprosil Chiral-OM (supercritical carbon dioxide: methanol, 50:50, 3.0 min, 70 mL/min) to give compound 30 (21.4 mg, white solid, Ret. time = 1.883 min, e.e. 100%) and compound 31 (24.8 mg, white solid, Ret. time = 2.256 min, e.e. 98.7%). The configuration and purity of the compound were confirmed by the chiral analysis method used in the synthesis of Example 30 above.

Compound 31: LC-MS (ESI) m/z 468.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.26 (d, J = 1.2Hz, 1H), 9.14 (d, J = 8.4Hz, 1H), 8.77 (s, 1H), 8.68 (s, 1H), 8.38 (s, 1H), 8.25 (s, 1H), 8.22 (d, J = 2.3Hz, 1H), 8.12 (s ,1H),7.96(d,J＝1.2Hz,1H),7.85(dd,J＝8.6,2.4Hz,1H),6.82(d,J＝8.5Hz,1H),5.12–5.02(m,1H),3.89(s,3H),3.83(s,3H),1.58(d,J＝7.1Hz,3H).

Example 32: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(trifluoromethyl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 32) and its hydrochloride (Compound 32-1 )

Step 1: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(trifluoromethyl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide and its hydrochloride

To a solution of triphosgene (25.5 mg, 0.086 mmol) in DCM (8.00 mL) at room temperature, 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) and DIEA (55.5 mg, 0.430 mmol) in DCM (4.00 mL) were added. The reaction mixture was stirred at room temperature for 2 hours. (6-(trifluoromethyl)pyridin-3-yl)methylamine (37.9 mg, 0.215 mmol) was added. The reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure to give a crude product (Compound 32) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 32-1) in the form of hydrochloride (20.0 mg, yield 17.6%, white solid). LC-MS(ESI)m/z 492.0[M+H] ⁺ . ¹ H NMR(400MHz, DMSO-d ₆ ) δ9.48(t,J＝6.2Hz,1H),9.27(d,J＝1.4Hz,1H),8.81(d,J＝0.7Hz ^, 1H) _, 8.80–8.77(m,1H),8.69(s,1H),8.39( s,1H),8.28(d,J＝0.7Hz,1H),8.14–8.12(m,1H),8.08–8.04(m,1H),7.97(d,J＝1.5Hz,1H),7.94–7.90(m,1H),4.63(d,J＝6.0Hz,2H),3.89(s,3H).

Example 33: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-ethoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 33) and its hydrochloride (Compound 33-1)

Step 1: Synthesis of 2-ethoxy-5-cyanopyridine

A solution of 2-chloro-5-cyanopyridine (1.00 g, 7.22 mmol) and sodium ethoxide (982 mg, 14.4 mmol) in anhydrous DMF (10.0 mL) was stirred at room temperature for 16 hours. The reaction mixture was poured into water (40.0 mL) to obtain a suspension. The mixture was filtered and the filter cake was washed with water (20.0 mL). The filter cake was dried in vacuo to obtain the target compound (850 mg, yield 79.5%, yellow solid). LC-MS (ESI) m/z 149.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.68 (d, J = 2.2 Hz, 1H), 8.14 (dd, J = 8.7, 2.4 Hz, 1H), 6.98 (d, J = 8.7 Hz, 1H), 4.39 (q, J = 7.1 Hz, 2H), 1.33 (t, J = 7.1 Hz, 3H). Step 2: Synthesis of (6-ethoxypyridin-3-yl)methanamine

At room temperature, a mixed solution of 2-ethoxy-5-cyanopyridine (300 mg, 2.02 mmol) and Raney nickel (300 mg) in aqueous ammonia (4.00 mL) and ethanol (12.0 mL) was stirred under a hydrogen atmosphere for 16 hours. After filtering the reaction solution, the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (260 mg, yield 84.3%, green oil).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-ethoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide and its hydrochloride

At room temperature, (6-ethoxypyridin-3-yl)methylamine (39.3 mg, 0.258 mmol) and DIEA (55.5 mg, 0.430 mmol) were added to a solution of CDI (45.3 mg, 0.279 mmol) in DMF (4.00 mL). After the reaction mixture was stirred at room temperature for 3 hours, 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added to the reaction mixture. The reaction mixture was stirred at 60°C for 16 hours. After the reaction mixture was cooled to room temperature, it was poured into water (15.0 mL) and extracted with EA (100 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product (Compound 33) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 33-1) in the form of hydrochloride (14.3 mg, yield 13.2%, off-white solid). LC-MS (ESI) m/z 468.3 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.30(t,J＝6.1Hz,1H),9.27–9.25(m,1H),8.79(s,1H),8.68(s,1H),8.39(s,1H),8.24(s,1H),8.16–8.14(m,1H),8.13(s,1H) ,7.98–7.95(m,1H),7.73(dd,J＝8.5,2.4Hz,1H),6.79(d,J＝8.6Hz,1H),4.41(d,J＝6.2Hz,2H),4.28(q,J＝7.0Hz,2H),3.89(s,3H),1.30(t,J＝7.0Hz,3H).

Example 34: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 34)

Step 1: Synthesis of 4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

Potassium acetate (527 mg, 5.37 mmol) and Pd(dppf)Cl 2 DCM complex (116 mg, 0.134 mmol) were added to a solution of 6-bromo-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine- ₃ -carbonitrile (1.00 g, 2.69 mmol) and biboronic acid pinacol ester (2.73 g, 10.7 mmol) in dry 1,4-dioxane (25.0 mL). Under argon protection, the reaction mixture was stirred at 90°C for 5 hours. The reaction mixture was cooled to room temperature and poured into EA (80.0 mL) to obtain a black solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (5.20 g, crude product, black solid). LC-MS (ESI) m/z 420.2 [M+H] ⁺ .

Step 2: Synthesis of 6-hydroxy-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

At 0°C, sodium hydroxide (1.98 g, 49.6 mmol) was added to a solution of 4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (5.20 g, 12.4 mmol) in tetrahydrofuran (200 mL). Then, 30% aqueous hydrogen peroxide solution (10.1 mL, 99.2 mmol) was added dropwise. The reaction mixture was stirred at room temperature for 1 hour. Saturated aqueous ammonium chloride solution (80.0 mL) was added to the reaction mixture and stirred at room temperature for 30 minutes. The organic phase was separated and the aqueous phase was extracted with EA (80.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (290 mg, two-step yield 34.9%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:1). LC-MS (ESI) m/z 332.2 [M+Na] ⁺ .

Step 3: Synthesis of 6-(2-hydroxy-2-methylpropoxy)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile

To a solution of 6-hydroxy-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile in tetrahydrofuran (6.00 mL) was added an aqueous sodium hydroxide solution (2.0 N, 0.940 mL, 1.88 mmol). The reaction mixture was stirred at room temperature for 15 minutes and then 2,2-dimethyloxirane (0.837 mL, 9.38 mmol) was added. After sealing the tube, the reaction mixture was stirred at 90°C for 8 hours. The reaction solution was cooled to room temperature and poured into EA (50.0 mL) to obtain a yellow solution. The solution was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (255 mg, yield 71.3%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=3:1-1:2). LC-MS (ESI) m/z 404.2[M+Na] ⁺ .

Step 4: Synthesis of 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride

6-(2-Hydroxy-2-methylpropoxy)-4-(1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (255 mg, 0.669 mmol) was added to a methanol solution of hydrogen chloride (3.0 M, 5.00 mL). The reaction mixture was stirred at room temperature for 1 hour. After concentration under reduced pressure, the target compound (215 mg, yield 96.3%, light yellow solid) was obtained. LC-MS (ESI) m/z 298.1 [M+H] ⁺ .

Step 5: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

Triphosgene (191 mg, 0.644 mmol) was added to a mixture of (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (124 mg, 0.644 mmol) in aqueous sodium bicarbonate (10.0 mL) and DCM (15.0 mL). The reaction mixture was stirred at room temperature for 1 hour. It was extracted with DCM (15.0 mL×2). The combined organic phases were washed with saturated brine (15.0 mL×2), dried over anhydrous sodium sulfate, and filtered to obtain a yellow filtrate. TEA (0.179 mL, 1.29 mmol) and 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (215 mg, 0.644 mmol) were added to the above filtrate. The reaction mixture was stirred at room temperature for 15 hours. The reaction solution was concentrated under reduced pressure to obtain a crude product. The title compound (20.0 mg, yield 6.21%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 516.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 9.44–9.36 (m, 1H), 8.77 (s, 1H), 8.73–8.66 (m, 2H), 8.60 (s, 1H), 8.47 (s, 1H), 8.23 (s, 1H), 8.02–7.97 (m, 1H), 7.96–7.88 (m, 2H), 7.51 (s, 1H), 4.72 (s, 1H), 4.58–4.49 (m, 2H), 3.88 (s, 2H), 1.23 (s, 6H).

Example 35: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 35) and its hydrochloride (Compound 35-1)

Step 1: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide hydrochloride

1-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)ethan-1-amine (30.5 mg, 0.148 mmol) and DIEA (34.8 mg, 0.269 mmol) were added to a solution of CDI (28.4 mg, 0.175 mmol) in DMF (1.50 mL). After the reaction mixture was stirred at room temperature for 16 hours, 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (45.0 mg, 0.135 mmol) was added to the mixture. The reaction mixture was stirred at 50°C for 8 hours. The reaction mixture was poured into water (15.0 mL) and extracted with EA (80.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product (Compound 35) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 35-1) in the form of hydrochloride (19.2 mg, yield 24.8%, white solid). LC-MS (ESI) m/z 530.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.28(d,J＝8.4Hz,1H),8.75(s,1H),8.71–8.69(m,1H),8.68(d,J＝4.4Hz,1H),8.60(s,1H),8.55–8.53(m,1H),8.24(s,1H),8.1 3–8.09(m,1H),7.92(s,1H),7.91(d,J＝4.0Hz,1H),7.52–7.50(m,1H),5.2 2–5.13(m,1H),4.70(s,1H),3.87(s,2H),1.63(d,J＝7.0Hz,3H),1.22(s,6H ).

Example 36: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-methoxypyridin-3-yl)methyl)-1H-pyrazole - 1-carboxamide (Compound 36) and its hydrochloride (Compound 36-1)

Step 1: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-methoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide hydrochloride

At room temperature, (6-methoxypyridin-3-yl)methylamine (63.7 mg, 0.461 mmol) and DIEA (108 mg, 0.838 mmol) were added to a solution of CDI (88.3 mg, 0.545 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 16 hours. 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (140 mg, 0.419 mmol) was added to the mixture. The reaction mixture was stirred at 60°C for 6 hours. After the reaction mixture was cooled to room temperature, it was poured into water (15.0 mL) and extracted with EA (80.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product (Compound 36) . Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the target compound (Compound 36-1) in the form of hydrochloride (12.8 mg, yield 6.13%, yellow solid). LC-MS (ESI) m/z 462.1 [M+H] ⁺ . ¹ H NMR (400MHz, CD ₃ OD) δ8.66–8.65(m,1H),8.48(d,J＝2.1Hz,1H),8.35(s,1H),8.32–8.30(m,1H),8.28–8.24(m,1H),8.06–8.04(m,1H),7.43(d,J＝2 .1Hz,1H),7.33–7.28(m,1H),4.60(s,2H),4.11(s,3H),3.91(s,2H),1.34(s,6H).

Example 37: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 37)

Step 1: Synthesis of 4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

At room temperature, 1-(6-methoxypyridin-3-yl)ethyl-1-amine (46.5 mg, 0.306 mmol) and DIEA (65.8 mg, 0.509 mmol) were added to a solution of CDI (61.9 mg, 0.382 mmol) in DMF (2.00 mL). After the reaction mixture was stirred at room temperature for 2 hours, 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (85.0 mg, 0.255 mmol) was added to the reaction mixture. The reaction mixture was stirred at 55°C for 16 hours. After the reaction mixture was cooled to room temperature, it was poured into water (20.0 mL) and extracted with EA (100 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (45.0 mg, yield 37.1%, off-white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 476.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.12 (d, J = 8.4Hz, 1H), 8.73 (d, J = 0.6Hz, 1H), 8.70 (d, J = 2.1Hz, 1H), 8.60 (s, 1H), 8.23–8.20 (m, 2H), 7.85 (dd, J = 8.6, 2.5Hz, 1H), 7 .50(d,J＝2.1Hz,1H),6.81(d,J＝8.6Hz,1H),5.10–5.01(m,1H),4.70(s,1H),3.87(s,2H),3.83(s,3H),1.57(d,J＝7.1Hz,3H),1.22(s,6H).

Example 38: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-4-carboxamide (Compound 38)

Step 1: Synthesis of ethyl 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylate

DIEA (1.38 mL, 8.33 mmol) was added to a solution of 6-bromo-4-fluoropyrazolo[1,5-a]pyridine-3-carbonitrile (1.00 g, 4.17 mmol) and 1H-pyrazole-4-carboxylic acid ethyl ester (701 mg, 5.00 mmol) in N-methylpyrrolidone (6.00 mL). The reaction mixture was stirred at 90°C for 16 hours. The reaction mixture was cooled to room temperature and poured into water (20.0 mL) and extracted with EA (200 mL). The organic phase was washed with saturated brine (20.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (920 mg, yield 61.3%, yellow solid) was obtained by column chromatography separation and purification (PE: EA = 10: 1-4: 1). LC-MS(ESI)m/z 360.1,362.1[M+H] ⁺ .

Step 2: Synthesis of ethyl 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylate

Potassium carbonate (384 mg, 2.78 mmol) and Pd(dppf)Cl 2 DCM complex (59.8 mg, 0.069 mmol) were added to a mixed solution of 1-(6-bromo-3-cyanopyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (500 mg, 1.39 mmol) and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan- ₂ -yl)-1H-pyrazole (318 mg, 1.53 mmol) in water (1.20 mL) and 1,4-dioxane (6.00 mL). Under argon protection, the reaction mixture was stirred at 100°C for 16 hours. After the reaction mixture was cooled to room temperature, it was poured into water (20.0 mL) and extracted with EA (60.0 mL×2). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to remove the organic solvent to obtain a crude product, which was separated and purified by column chromatography (PE:EA=3:1-1:2) to obtain the target compound (390 mg, yield 77.7%, white solid).

Step 3: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylic acid

To a mixed solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (120 mg, 0.332 mmol) in water (1.00 mL) and ethanol (6.00 mL) was added sodium hydroxide (26.6 mg, 0.664 mmol). The reaction mixture was stirred at room temperature for 16 hours. After the reaction mixture was concentrated under reduced pressure to remove the organic solvent, it was added to water (3.00 mL) and the pH was adjusted to 5 with 1.0 M hydrochloric acid solution to obtain a suspension. The suspension was filtered, the filter cake was washed with water (10.0 mL), and the target compound (100 mg, yield 90.3%, white solid) was obtained after drying. LC-MS (ESI) m/z 334.1 [M+H] ⁺ .

Step 4: Synthesis of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-4-carboxamide

At room temperature, EDCI (86.3 mg, 0.450 mmol), HOBt (60.8 mg, 0.450 mmol) and DIEA (77.5 mg, 0.600 mmol) were added to a solution of 1-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1H-pyrazole-4-carboxylic acid (100 mg, 0.300 mmol) and (6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (63.4 mg, 0.330 mmol) in DMF (2.00 mL). The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was poured into water (15.0 mL) and extracted with EA (80.0 mL). The organic phase was washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (15.3 mg, yield 10.0%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 508.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ9.39 (s, 1H), 8.98 (t, J=6.0 Hz, 1H), 8.85 (s, 1H), 8.72 (s, 1H), 8.69 (d, J=4.2 Hz, 1H), 8.45 (s, 1H), 8.42 (s, 1H), 8.30 (s, 1H), 8.21 (s, 1H), 8.16 (s, 1H), 7.98–7.89 (m, 3H), 4.55 (d, J=5.4 Hz, 2H), 3.89 (s, 3H).

Example 39: Synthesis of 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- (1-(6-methoxypyridin-3-yl)ethyl)-1,3,4-thiadiazole-2-carboxamide (Compound 39)

Step 1: 6-(1-methyl-1H-pyrazol-4-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane- Synthesis of 2-pyrazolo[1,5-a]pyridine-3-carbonitrile

Potassium acetate (106 mg, 1.08 mmol) and Pd(dppf)Cl 2 DCM complex (23.2 mg, 0.027 mmol) were added to a solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (200 mg, 0.539 mmol) and biboronic acid pinacol ester (684 mg, 2.69 mmol) in dry _1,4 -dioxane (5.00 mL). The reaction mixture was stirred at 90°C for 16 hours under argon protection. The reaction mixture was cooled to room temperature and poured into water (20.0 mL), and extracted with EA (50.0 mL x 3). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (200 mg, crude product, black solid). LC-MS(ESI)m/z 350.1[M+H] ⁺ .

Step 2: Synthesis of ethyl 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,3,4-thiadiazole-2-carboxylate

4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (9.95 mg, 0.017 mmol), palladium acetate (3.86 mg, 0.017 mmol) and N-methylmorpholine (174 mg, 1.72 mmol) were added to a mixed solution of 6-(1-methyl-1H-pyrazol-4-yl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile (200 mg, 0.573 mmol) and ethyl 5-bromo-1,3,4-thiadiazole-2-carboxylate (163 mg, 0.687 mmol) in toluene (6.00 mL) and water (3.00 mL). The reaction mixture was stirred at 80°C for 5 hours under argon protection. The reaction solution was concentrated under reduced pressure and added to water (30.0 mL) and EA (50.0 mL). The organic phase was separated and the aqueous phase was extracted with a mixed solvent (DCM: methanol = 10:1, 80.0 mL x 3). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (70.0 mg, two-step yield 34.3%, yellow solid). LC-MS (ESI) m/z 380.0 [M + H] ⁺ .

Step 3: Synthesis of potassium 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,3,4-thiadiazole-2-carboxylate

To a mixed solution of ethyl 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,3,4-thiadiazole-2-carboxylate (70.0 mg, 0.185 mmol) in water (1.00 mL) and ethanol (3.00 mL) was added potassium hydroxide (12.8 mg, 0.194 mmol) at 0°C. The reaction mixture was stirred at room temperature for 5 hours. The reaction mixture was concentrated under reduced pressure to obtain the target compound (80.0 mg, crude product, yellow solid). LC-MS (ESI) m/z 393.2 [M+H+41] ⁺ .

Step 4: Synthesis of 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-1,3,4-thiadiazole-2-carboxamide

At room temperature, EDCI (59.1 mg, 0.308 mmol), HOBt (41.6 mg, 0.308 mmol) and DIEA (53.1 mg, 0.411 mmol) were added to a DMF (3.00 mL) solution of potassium 5-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-1,3,4-thiadiazole-2-carboxylate (80.0 mg, 0.205 mmol) and 1-(6-methoxypyridin-3-yl)ethan-1-amine (37.5 mg, 0.247 mmol). After the reaction mixture was stirred at room temperature for 16 hours, the reaction mixture was stirred at 50°C for 4 hours. The reaction mixture was poured into EA (100 mL) and washed with saturated brine (15.0 mL×3). The organic phase was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (4.05 mg, two-step yield 4.52%, yellow solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 486.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ10.00(d,J＝8.4Hz,1H),9.49(d,J＝1.4Hz,1H),8.76(s,1H),8.45(s,1H),8.34(d,J＝1.4Hz,1H),8.23(d,J＝2.4Hz,1H),8.18(s, 1H),7.85(dd,J＝8.6,2.5Hz,1H),6.83(d,J＝8.5Hz,1H),5.23–5.18(m,1H),3.90(s,3H),3.83(s,3H),1.57(d,J＝7.1Hz,3H).

Example 40: (R)-3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 40)

3-(3-Cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (50 mg dissolved in about 20 mL of ethanol, injection volume 1.5 mL) was separated by Waters SFC 150 (room temperature, 100 bar, 214 nm) and 250*25 mm 10 μm Dr.maish Reprosil Chiral-OM (supercritical carbon dioxide:ethanol, 65:35, 5.0 min, 70 mL/min) to give compound 40 (15.2 mg, white solid, Ret. time = 3.609 min, ee 99.1%) and compound 41 (20.7 mg, white solid, Ret. time = 4.225 min, ee 98.2%). Chiral analysis method: Chiral column: OD-H 250*4.6mm 5μm; mobile phase: A: Supercritical CO ₂ , B: EtOH (0.1% DEA); gradient: A 60%, B 40% for 12min; flow rate: 2.8mL/min; column temperature: 35°C.

Compound 40: LC-MS (ESI) m/z 469.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ9.24(d,J＝1.2Hz,1H),8.68(s,1H),8.38(s,1H),8.14(d,J＝2.3Hz,1H),8.12(s,1H),7.88(d,J＝1.2Hz,1H),7.74(dd,J＝8.6,2.5Hz,1H),6.78(d,J＝8. 5Hz,1H),6.61(d,J＝8.0Hz,1H),6.37–6.33(m,1H),4.93–4.84(m,1H),4.63–4.56(m,2H),4.39–4.30(m,2H),3.88(s,3H),3.82(s,3H),1.42(d,J＝7 .1Hz,3H).

Example 41: Synthesis of (S)-3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide (Compound 41)

Step 1: Synthesis of (S)-3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-methoxypyridin-3-yl)ethyl)-2,5-dihydro-1H-pyrrole-1-carboxamide

To a solution of CDI (49.6 mg, 0.306 mmol) in DMF (2.00 mL) at room temperature, (S)-1-(6-methoxypyridin-3-yl)ethan-1-amine (34.9 mg, 0.230 mmol) and DIEA (39.5 mg, 0.306 mmol) were added. The reaction mixture was stirred at room temperature for 2 hours. 4-(2,5-dihydro-1H-pyrrol-3-yl)-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (50.0 mg, 0.153 mmol) was added to the mixture. The reaction mixture was stirred at 55°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. Purification by preparative HPLC (acetonitrile/water containing 0.05% ammonium bicarbonate) gave the target compound (27.0 mg, yield 37.7%, Ret. time = 4.220 min, ee 96.2%, white solid). Chiral analysis method (same as the method in the synthesis of Example 40: Chiral column: OD-H 250*4.6mm 5μm; mobile phase: A: Supercritical CO ₂ , B: EtOH (0.1% DEA); gradient: A 60%, B 40% for 12min; flow rate: 2.8mL/min; column temperature: 35°C). LC-MS (ESI) m/z 469.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ )δ9.24(d,J＝1.3Hz,1H),8.68(s,1H),8.38(s,1H),8.14(d,J＝2.4Hz,1H),8.12(s,1H),7.88(d,J＝1.2Hz,1H),7.73(dd,J＝8.6,2.5Hz,1H),6.78(d,J＝8. 5Hz,1H),6.61(d,J＝8.0Hz,1H),6.37–6.34(m,1H),4.93–4.84(m,1H),4.62–4.58(m,2H),4.37–4.33(m,2H),3.88(s,3H),3.82(s,3H),1.42(d,J＝7 .1Hz,3H).

Example 42: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-isopropoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 42)

Step 1: Synthesis of (6-isopropoxypyridin-3-yl)methylamine

At room temperature, a solution of 6-isopropoxy-3-cyanopyridine (300 mg, 1.85 mmol) and Raney nickel (300 mg) in aqueous ammonia (28%, 4.00 mL) and ethanol (14.0 mL) was stirred under hydrogen atmosphere for 16 hours. The mixture was filtered and the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (270 mg, yield 87.8%, green oil). ¹ H NMR (400 MHz, DMSO-d ₆ ) δ 8.00 (s, 1H), 7.63 (s, 1H), 6.69 (s, 1H), 5.27–5.14 (m, 1H), 3.92–3.42 (m, 2H), 2.34–1.43 (m, 2H), 1.26 (d, J=6.1 Hz, 6H).

Step 2: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-isopropoxypyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

To a solution of CDI (79.6 mg, 0.491 mmol) in DMF (4.00 mL) at room temperature, (6-isopropoxypyridin-3-yl)methylamine (61.2 mg, 0.368 mmol) and DIEA (63.5 mg, 0.491 mmol) were added. After the reaction mixture was stirred at room temperature for 2 hours, 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (80.0 mg, 0.246 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. Purification by preparative HPLC (acetonitrile/water containing 0.05% hydrochloric acid) gave the crude target compound. The target compound (9.18 mg, yield 7.76%, white solid) was obtained by supercritical fluid chromatography (carbon dioxide/methanol). LC-MS (ESI) m/z 482.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.29 (t, J = 6.3Hz, 1H), 9.26 (d, J = 1.4Hz, 1H), 8.79 (s, 1H), 8.68 (s, 1H), 8.39 (s, 1H), 8.24 (s, 1H), 8.14 (d, J = 2.3Hz, 1H), 8.13 (s ,1H),7.96(d,J＝1.4Hz,1H),7.70(dd,J＝8.5,2.4Hz,1H),6.73(d,J＝8.5Hz,1H),5.26–5.19(m,1H),4.40(d,J＝6.1Hz,2H),3.89(s,3H),1.27(d,J＝6.2Hz,6 H).

Example 43: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrrole-1-carboxamide (Compound 43)

Step 1: Synthesis of 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrrole

At 0°C, tetrabutylammonium fluoride (1.0M in THF, 2.00mL, 2.00mmol) was added to a solution of 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1-(triisopropylsilyl)-1H-pyrrole (350mg, 1.00mmol) in tetrahydrofuran (6.00mL). The reaction mixture was stirred at room temperature for 2 hours. Saturated ammonium chloride solution (15.0mL) was added and extracted with EA (50.0mL x 3). The combined organic phases were washed with saturated brine (15.0mL x 3), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (190mg, yield 98.3%, yellow solid). LC-MS (ESI) m/z 194.1 [M+H] ⁺ .

Step 2: Synthesis of N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrrole-1-carboxamide

At room temperature, 2-(6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methylamine (227 mg, 1.18 mmol) was added to a solution of CDI (239 mg, 1.48 mmol) in DMF (5.00 mL). The reaction mixture was stirred at room temperature for 16 hours to obtain a reaction solution. Sodium hydride (51.2 mg, 1.28 mmol) was added to a solution of 3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrrole (190 mg, 0.984 mmol) in DMF (5.00 mL). The reaction mixture was stirred at 0°C for 2 hours and then the above reaction solution was added. The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was poured into saturated ammonium chloride (20.0 mL) and extracted with EA (60.0 mL × 3). The combined organic phases were washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (220 mg, crude product, yellow solid). LC-MS (ESI) m/z 412.2 [M+H] ⁺ .

Step 3: Synthesis of 3-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-1H-pyrrole-1-carboxamide

To a solution of 3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl trifluoromethanesulfonate (160 mg, 0.431 mmol) and N-((6-(4-fluoro-1H-pyrazol-1-yl)pyridin-3-yl)methyl)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrrole-1-carboxamide (213 mg, 0.517 mmol) in water (1.00 mL) and 1,4-dioxane (10.0 mL) were added sodium carbonate (91.3 mg, 0.862 mmol) and Pd(dppf)Cl ₂ .DCM (18.6 mg, 0.022 mmol). Under argon protection, the reaction mixture was stirred at 100° C. for 5 hours. The reaction mixture was concentrated under reduced pressure to obtain a crude product. The crude product of the target compound was obtained by column chromatography separation and purification (PE:EA=3:1-1:2). The target compound (9.02 mg, yield 3.79%, off-white solid) was obtained by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 507.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.20 (d, J = 1.4Hz, 1H), 9.06 (t, J = 5.5Hz, 1H), 8.70 (dd, J = 4.6, 0.6Hz, 1H), 8.66 (s, 1H), 8.48 (d, J = 1.6Hz, 1H), 8.40 (s, 1H), 8.12 (s ,1H),8.02–7.98(m,1H),7.94–7.90(m,3H),7.83(d,J＝1.4Hz,1H),7.60–7.57(m,1H),6.72–6.69(m,1H),4.56(d,J＝5.4Hz,2H),3.88(s,3H).

Example 44: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(pyrrolidin-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 44)

Step 1: Synthesis of 6-(pyrrolidin-1-yl)-3-cyanopyridine

Potassium carbonate (1.99 g, 14.4 mmol) was added to a DMF (10.0 mL) solution of 6-chloro-3-cyanopyridine (1.00 g, 7.22 mmol) and tetrahydropyrrole (616 mg, 8.66 mmol). Under argon protection, the reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (200 mL). It was washed with saturated brine (20.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.15 g, yield 92.0%, light yellow solid) was obtained by column chromatography separation and purification (PE: EA = 10: 1). LC-MS (ESI) m/z 174.3 [M + H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.45 (d, J = 1.8 Hz, 1H), 7.79 ( dd, J = 9.0, 2.3 Hz, 1H), 6.53 ( d, J = 8.9 Hz, 1H), 3.54–3.34 (m, 4H), 2.01–1.88 (m, 4H).

Step 2: Synthesis of (6-(pyrrolidin-1-yl)pyridin-3-yl)methanamine

To a solution of 6-(pyrrolidin-1-yl)-3-cyanopyridine (100 mg, 0.577 mmol) in aqueous ammonia (28%, 1.50 mL) and ethanol (10.0 mL) was added Raney nickel (30.0 mg). The reaction mixture was stirred under hydrogen atmosphere at room temperature for 16 hours. The mixture was filtered and the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (90.0 mg, yield 88.0%, white solid). LC-MS (ESI) m/z 178.2 [M+H] ⁺ . ¹ H NMR (400MHz, MeOH-d ₄ ) δ7.94 (d, J = 2.1 Hz, 1H), 7.53 (dd, J = 8.7, 2.4 Hz, 1H), 6.48 (d, J = 8.7 Hz, 1H), 3.64 (s, 2H), 3.43–3.39 (m, 4H), 2.04–2.00 (m, 4H).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(pyrrolidin-1-yl)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

At 0°C, (6-(pyrrolidin-1-yl)pyridin-3-yl)methylamine (57.1 mg, 0.322 mmol) and DIEA (55.6 mg, 0.430 mmol) were added to a solution of CDI (69.7 mg, 0.430 mmol) in dry DMF (3.00 mL). The reaction mixture was stirred at room temperature for 2 hours, and then 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL), washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (20.4 mg, yield 17.7%, yellow solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 493.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.26 (d, J = 1.0Hz, 1H), 9.16 (t, J = 6.1Hz, 1H), 8.78 (s, 1H), 8.68 (s, 1H), 8.24–8.19 (m, 2H), 8.13 (s, 1H), 8.07 (d, J = 1.9Hz, 1H), 7 .96(d,J＝1.0Hz,1H),7.53(dd,J＝8.6,2.2Hz,1H),6.42(d,J＝8.7Hz,1H),4.31(d,J＝6.1Hz,2H),3.89(s,3H),3.37–3.33(m,4H),1.95–1.89(m,4H).

Example 45: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-(trifluoromethoxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 45)

Step 1: Synthesis of 3-cyano-6-(trifluoromethoxy)pyridine

Under argon atmosphere, a solution of 2-hydroxy-5-cyanopyridine (500 mg, 4.16 mmol) and 1-trifluoromethyl-1,2-benzidoyl -3(H)-one (658 mg, 2.08 mmol) in nitromethane (6.00 mL) was stirred at 100°C for 16 hours. The reaction mixture was cooled to room temperature and poured into DCM (25.0 mL). Filtered, the filter cake was washed with DCM (10.0 mL). The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (60.0 mg, yield 7.66%, off-white solid) was obtained by column chromatography separation and purification (PE:EA=20:1). ¹ H NMR (400 MHz, DMSO-d ₆ )δ8.95–8.89 (m, 1H), 8.55 (dd, J=8.6, 2.3 Hz, 1H), 7.57–7.50 (m, 1H). ¹⁹ F NMR (376MHz, DMSO-d ₆ ) δ-55.37 (s).

Step 2: Synthesis of (6-(trifluoromethoxy)pyridin-3-yl)methanamine

At room temperature, a mixed solution of 3-cyano-6-(trifluoromethoxy)pyridine (60.0 mg, 0.319 mmol) and Raney nickel (30.0 mg) in aqueous ammonia (28%, 1.00 mL) and ethanol (5.00 mL) was stirred under a hydrogen atmosphere for 16 hours. The reaction solution was filtered and the filter cake was washed with ethanol (5.00 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (45.0 mg, yield 73.4%, green oil). LC-MS (ESI) m/z 193.3 [M+H] ⁺ . ¹⁹ F NMR (376 MHz, DMSO-d ₆ ) δ-55.07 (s).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-(trifluoromethoxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

To a solution of CDI (44.8 mg, 0.276 mmol) in dry DMF (2.00 mL) at room temperature, (6-(trifluoromethoxy)pyridin-3-yl)methylamine (42.5 mg, 0.221 mmol) and DIEA (47.6 mg, 0.368 mmol) were added. The reaction mixture was stirred at room temperature for 2 hours, and then 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (60.0 mg, 0.184 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (120 mL). Washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. Concentrated under reduced pressure. The residue was purified by preparative method (acetonitrile/water containing 0.05% formic acid) to give the target compound (5.08 mg, yield 5.44%, white solid). LC-MS (ESI) m/z 508.1 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.42(t,J＝6.2Hz,1H),9.27(d,J＝1.3Hz,1H),8.80(s,1H),8.68(s,1H),8.39–8.37(m,2H),8.26(s,1H),8.13(s,1H),8.03(dd ,J＝8.4,2.4Hz,1H),7.97(d,J＝1.3Hz,1H),7.31(d,J＝8.4Hz,1H),4.54(d,J＝6.2Hz,2H),3.89(s,3H).

Example 46: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 46)

Step 1: Synthesis of 6-((tetrahydro-2H-pyran-4-yl)oxy)-3-cyanopyridine

Under argon protection, in an ice-water bath, add tetrahydro-2H-pyran-4-ol (1.00 g, 9.83 mmol) to a solution of sodium hydride (426 mg, 10.6 mmol) in dry DMF (10.0 mL), and stir the reaction for 10 minutes in an ice bath, then add a solution of 6-fluoro-3-cyanopyridine (1.00 g, 8.19 mmol) in dry DMF (5.00 mL). The reaction mixture was stirred at room temperature for 16 hours. Saturated aqueous ammonium chloride solution (30.0 mL) was added to the reaction solution. Extracted with EA (100 mL × 2). The combined organic phases were washed with saturated brine (25.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.32 g, yield 78.9%, white solid) was obtained by column chromatography separation and purification (PE: EA = 10: 1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.71–8.65(m,1H),8.15(dd,J＝8.7,2.4Hz,1H),7.03–6.96(m,1H),5.34–5.19(m,1H),3.93–3.79(m,2H),3.57–3.42(m,2H), 2.11–1.90(m,2H),1.74–1.57(m,2H).

Step 2: Synthesis of (6-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-3-yl)methanamine

To a mixed solution of 6-((tetrahydro-2H-pyran-4-yl)oxy)-3-cyanopyridine (100 mg, 0.490 mmol) in aqueous ammonia (28%, 1.50 mL) and ethanol (10.0 mL) was added Raney nickel (30.0 mg). The reaction mixture was stirred under hydrogen atmosphere at room temperature for 16 hours. The mixture was filtered and the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (90.0 mg, yield 88.3%, colorless oil). ¹ H NMR (400MHz, MeOH-d ₄ ) δ8.05(d,J＝2.1Hz,1H),7.67(dd,J＝8.5,2.4Hz,1H),6.75(d,J＝8.5Hz,1H),5.19–5.11(m,1H),3.98–3.92(m,2H),3.72(s,2H),3. 63–3.56(m,2H),2.08–2.00(m,2H),1.78–1.67(m,2H).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

At 0°C, (6-((tetrahydro-2H-pyran-4-yl)oxy)pyridin-3-yl)methylamine (67.1 mg, 0.322 mmol) and DIEA (55.6 mg, 0.430 mmol) were added to a solution of CDI (69.7 mg, 0.430 mmol) in dry DMF (3.00 mL). After the reaction mixture was stirred at room temperature for 2 hours, 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (24.5 mg, yield 21.8%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 524.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ9.30 (t, J=6.2 Hz, 1H), 9.26 (d, J=1.1 Hz, 1H), 8.79 (s, 1H), 8.68 (s, 1H), 8.39 (s, 1H), 8.24 (s, 1H), 8.14 (d, J=2.1 Hz, 1H), 8.13 (s, 1H), 7.96 (d, J=1.1 Hz, 1H), 7.73 (dd, J= 8.5,2.3Hz,1H),6.79(d,J＝8.5Hz,1H),5.20–5.13(m,1H),4.41(d,J＝6.1Hz,2H),3.89(s,3H),3.88–3.82(m,2H),3.52–3.45(m,2H),2.02–1.95(m,2 H),1.66–1.56(m,2H).

Example 47: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-morpholinopyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 47)

Step 1: Synthesis of 6-morpholino-3-cyanopyridine

At room temperature, DIEA (1.19 mL, 7.22 mmol) and morpholine (0.692 mL, 7.94 mmol) were added dropwise to a solution of 6-chloro-3-cyanopyridine (1.00 g, 7.22 mmol) in water (2.50 mL) and DMF (8.00 mL). Under argon protection, the reaction mixture was stirred at 90 ° C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (200 mL). Washed with saturated brine (25.0 mL × 5), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (1.30 g, yield 95.2%, yellow solid). LC-MS (ESI) m/z 190.1 [M + H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.52–8.49 (m, 1H), 7.88 (dd, J = 9.1, 2.4Hz, 1H), 6.95–6.90 (m, 1H), 3.70–3.66 (m, 4H), 3.64–3.60 (m, 4H).

Step 2: Synthesis of (6-morpholinopyridin-3-yl)methanamine

To a solution of 6-morpholino-3-cyanopyridine (100 mg, 0.528 mmol) in aqueous ammonia (28%, 1.50 mL) and ethanol (10.0 mL) was added Raney nickel (30.0 mg). The reaction mixture was stirred under hydrogen atmosphere at room temperature for 16 hours. The mixture was filtered and the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (90.0 mg, yield 88.1%, off-white solid). LC-MS (ESI) m/z 177.1 [M-16] ⁺ . ¹ H NMR (400MHz, MeOH-d ₄ ) δ 8.07 (d, J = 2.2 Hz, 1H), 7.60 ( dd, J = 8.7, 2.5 Hz, 1H), 6.81 ( d, J = 8.7 Hz, 1H), 3.80–3.76 (m, 4H), 3.68 (s, 2H), 3.45–3.41 (m, 4H).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-morpholinopyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

At 0°C, (6-morpholinopyridin-3-yl)methylamine (62.3 mg, 0.322 mmol) and DIEA (55.6 mg, 0.430 mmol) were added to a solution of CDI (69.7 mg, 0.430 mmol) in dry DMF (3.00 mL). The reaction mixture was stirred at room temperature for 2 hours, and then 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Washed with saturated brine (15.0 mL × 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (14.7 mg, yield 13.5%, white solid) was obtained by purification by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 509.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.26 (d, J = 1.4Hz, 1H), 9.22 (t, J = 6.2Hz, 1H), 8.78 (s, 1H), 8.68 (s, 1H), 8.39 (s, 1H), 8.23 (s, 1H), 8.15 (d, J = 2.2Hz, 1H), 8.13 (s ,1H),7.96(d,J＝1.4Hz,1H),7.60(dd,J＝8.7,2.4Hz,1H),6.83(d,J＝8.8Hz,1H),4.35(d,J＝6.1Hz,2H),3.89(s,3H),3.70–3.67(m,4H),3.43–3.39(m,4H) .

Example 48: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N- ((6-((tetrahydrofuran-3-yl)oxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide (Compound 48)

Step 1: Synthesis of 6-((tetrahydrofuran-3-yl)oxy)-3-cyanopyridine

Under argon protection, tetrahydrofuran-3-ol (866 mg, 9.83 mmol) was added to a solution of sodium hydride (426 mg, 10.6 mmol) in dry DMF (10.0 mL) in an ice-water bath, and the mixture was stirred for 10 minutes in an ice bath, followed by the addition of a solution of 6-fluoro-3-cyanopyridine (1.00 g, 8.19 mmol) in dry DMF (5.00 mL). The reaction mixture was stirred at room temperature for 16 hours. Saturated aqueous ammonium chloride solution (30.0 mL) was added to the reaction solution, and the mixture was extracted with EA (100 mL x 2). The combined organic phases were washed with saturated brine (25.0 mL x 3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (1.30 g, yield 83.5%, white solid) was obtained by column chromatography separation and purification (PE: EA = 5: 1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.71–8.68(m,1H),8.16(dd,J＝8.7,2.2Hz,1H),7.01(d,J＝8.7Hz,1H),5.59–5.55(m,1H),3.93–3.82(m,2H),3.81–3.73(m,2H) ,2.32–2.20(m,1H),2.06–1.98(m,1H).

Step 2: Synthesis of (6-((tetrahydrofuran-3-yl)oxy)pyridin-3-yl)methanamine

To a solution of 6-((tetrahydrofuran-3-yl)oxy)-3-cyanopyridine (100 mg, 0.526 mmol) in aqueous ammonia (28%, 1.50 mL) and ethanol (10.0 mL) was added Raney nickel (30.0 mg). The reaction mixture was stirred under hydrogen atmosphere at room temperature for 16 hours. The mixture was filtered and the filter cake was washed with ethanol (10.0 mL). The filtrate was concentrated under reduced pressure to obtain the target compound (95.0 mg, yield 93.0%, colorless oil). ¹ H NMR (400MHz, MeOH-d ₄ ) δ8.06(d,J＝2.4Hz,1H),7.68(dd,J＝8.5,2.5Hz,1H),6.75(d,J＝8.5Hz,1H),5.52–5.46(m,1H),4.02–3.91(m,2H),3.90–3.84(m,2 H),3.72(s,2H),2.31–2.21(m,1H),2.14–2.06(m,1H).

Step 3: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-((6-((tetrahydrofuran-3-yl)oxy)pyridin-3-yl)methyl)-1H-pyrazole-1-carboxamide

To a solution of CDI (69.7 mg, 0.430 mmol) in dry DMF (3.00 mL) at 0°C, (6-((tetrahydrofuran-3-yl)oxy)pyridin-3-yl)methylamine (62.6 mg, 0.322 mmol) and DIEA (55.6 mg, 0.430 mmol) were added. The reaction mixture was stirred at room temperature for 2 hours, and then 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (70.0 mg, 0.215 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and poured into EA (100 mL). Washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (19.8 mg, yield 18.0%, white solid) was purified by preparative HPLC (acetonitrile/water containing 0.05% formic acid). LC-MS (ESI) m/z 510.2 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ9.31 (t, J=6.1 Hz, 1H), 9.26 (d, J=1.2 Hz, 1H), 8.79 (s, 1H), 8.68 (s, 1H), 8.39 (s, 1H), 8.24 (s, 1H), 8.15 (d, J=2.0 Hz, 1H), 8.13 (s, 1H), 7.96 (d, J=1.3 Hz, 1H), 7.74 (dd, J=8.5, 2.4 Hz, 1H). z,1H),6.81(d,J＝8.5Hz,1H),5.51–5.46(m,1H),4.42(d,J＝6.1Hz,2H),3.93–3.90(m,1H),3.89(s,3H),3.86–3.80(m,1H),3.78–3.72(m,2H),2.28– 2.17(m,1H),2.02–1.93(m,1H).

Example 49: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 49)

Step 1: Synthesis of 2-isopropoxy-5-cyanopyridine

At 0°C, add isopropanol (8.28 mL, 108 mmol) to a solution of potassium tert-butoxide (12.1 g, 108 mmol) in anhydrous tetrahydrofuran (300 mL). The reaction mixture was stirred at 0°C for 5 minutes. 6-Chloronicotinonitrile (10.0 g, 72.2 mmol) was added to the reaction mixture and the reaction was continued to stir at room temperature for 2 hours. The reaction mixture was quenched with saturated ammonium chloride (120 mL) and extracted with EA (200 mL×3). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (10.0 g, yield 85.4%, white solid) was obtained by column chromatography separation and purification (PE:EA=100:1-20:1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.67 (d, J = 2.0 Hz, 1H), 8.12 ( dd, J = 8.7, 2.4 Hz, 1H), 6.93 ( d, J = 8.7 Hz, 1H), 5.36–5.27 ( m, 1H), 1.31 ( d, J = 6.2 Hz, 6H).

Step 2: Synthesis of 1-(6-isopropoxypyridin-3-yl)ethan-1-one

Under argon protection at 0°C, methylmagnesium bromide solution (3.0M in THF, 61.7mL, 185mmol) was added dropwise to a solution of 2-isopropoxy-5-cyanopyridine (10.0g, 61.7mmol) in anhydrous tetrahydrofuran (180mL). The reaction mixture was stirred at room temperature for 16 hours. The reaction solution was quenched with dilute hydrochloric acid (1.0M, 100mL) at 0°C and extracted with EA (200mL×3). The combined organic phases were dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (5.00g, yield 49.8%, yellow oil) was obtained by column chromatography separation and purification (PE:EA＝100:1-20:1). LC-MS(ESI)m/z 180.2[M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ 8.81 (d, J = 2.4 Hz, 1H), 8.14 ( dd, J = 8.7, 2.4 Hz, 1H), 6.84 ( d, J = 8.7 Hz, 1H), 5.40–5.29 ( m, 1H), 2.54 ( s, 3H), 1.32 ( d, J = 6.2 Hz, 6H).

Step 3: Synthesis of (R,E)-N-(1-(6-isopropoxypyridin-3-yl)ethylidene)-2-methylpropyl-2-sulfenamide

Tetraethyl titanate (11.7 mL, 55.8 mmol) was added to a solution of 1-(6-isopropoxypyridin-3-yl)ethan-1-one (5.00 g, 27.9 mmol) and (R)-2-methylpropyl-2-sulfenamide (3.72 g, 30.7 mmol) in anhydrous tetrahydrofuran (80.0 mL). The reaction mixture was stirred at 75°C for 16 hours. The reaction mixture was concentrated under reduced pressure and diluted with EA (100 mL), and water (10.0 mL) was added dropwise to obtain a suspension. The suspension was filtered through diatomaceous earth, and the filter cake was washed with EA (15.0 mL). The filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (5.20 g, yield 66.0%, yellow oil) was obtained by column chromatography separation and purification (PE:EA=20:1-4:1). ¹ H NMR (400MHz, DMSO-d ₆ ) δ8.72(d,J＝2.4Hz,1H),8.18(dd,J＝8.8,2.5Hz,1H),6.84(d,J＝8.8Hz,1H),5.36–5.29(m,1H),2.70(s,3H),1.31(d,J＝6.2Hz,6H),1 .21(s,9H).

Step 4: Synthesis of (R)-N-((S)-1-(6-isopropoxypyridin-3-yl)ethyl)-2-methylpropyl-2-sulfenamide

Under argon protection at -70℃, lithium tri-sec-butylborohydride (1.0M in THF, 36.8mL, 36.8mmol) was added dropwise to a solution of (R,E)-N-(1-(6-isopropoxypyridin-3-yl)ethylidene)-2-methylpropyl-2-sulfinamide (5.20g, 18.4mmol) in tetrahydrofuran (70.0mL). The reaction mixture was stirred at -70℃ under argon protection for 2 hours. The reaction mixture was quenched with saturated ammonium chloride (150mL) and extracted with EA (120mL×3). The combined organic phases were washed with saturated ammonium chloride (30.0mL×2) and saturated brine (15.0mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The title compound (4.80 g, yield 91.7%, yellow solid) was obtained by column chromatography separation and purification (PE:EA=4:1-dichloromethane:methanol=15:1). LC-MS (ESI) m/z 285.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ ) δ8.07 (d, J=2.4 Hz, 1H), 7.64 (dd, J=8.6, 2.5 Hz, 1H), 6.70 (d, J=8.6 Hz, 1H), 5.36 (d, J=5.1 Hz, 1H), 5.24-5.18 (m, 1H), 4.41-4.33 (m, 1H), 1.44 (d, J=6.7 Hz, 3H), 1.29-1.25 (m, 6H), 1.09 (s, 9H).

Step 5: Synthesis of (S)-1-(6-isopropoxypyridin-3-yl)ethan-1-amine

To a solution of (R)-N-((S)-1-(6-isopropoxypyridin-3-yl)ethyl)-2-methylpropyl-2-sulfenamide (4.80 g, 16.9 mmol) in methanol (40.0 mL) was added a solution of hydrochloric acid in 1,4-dioxane (4.0 M, 40.0 mL, 160 mmol) at 0°C. The reaction mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure to obtain a crude product. The target compound (2.50 g, yield 82.2%, light yellow oil) was obtained by column chromatography separation and purification (EA: MeOH: TEA = 100: 1: 1-20: 1: 1). ¹ H NMR (400MHz, MeOH-d ₄ ) δ8.05 (d, J = 2.5 Hz, 1H), 7.69 (dd, J = 8.6, 2.5 Hz, 1H), 6.70 (d, J = 8.6 Hz, 1H), 5.22–5.12 (m, 1H), 4.03 (q, J = 6.7 Hz, 1H), 1.38 (d, J = 6. 7Hz, 3H), 1.30 (d, J = 6.2Hz, 6H).

Step 6: Synthesis of (S)-phenyl (1-(6-isopropoxypyridin-3-yl)ethyl)carbamate

To a solution of (S)-1-(6-isopropoxypyridin-3-yl)ethan-1-amine (500 mg, 2.77 mmol) and TEA (0.770 mL, 5.54 mmol) in DCM (25.0 mL) was added a solution of phenyl chloroformate (521 mg, 3.33 mmol) in DCM (5.00 mL) over 1 minute. The reaction mixture was stirred at room temperature for 30 minutes. The reaction solution was concentrated under reduced pressure to obtain a crude product. The target compound (800 mg, yield 96.0%, white solid) was obtained by column chromatography separation and purification (PE:EA=100:1-10:1). LC-MS (ESI) m/z 301.2 [M+H] ⁺ .

Step 7: Synthesis of (S)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

To a solution of 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (900 mg, 2.76 mmol) and DIEA (0.912 mL, 5.52 mmol) in DMF (10.0 mL) at room temperature was added (S)-phenyl(1-(6-isopropoxypyridin-3-yl)ethyl)carbamate (996 mg, 3.32 mmol). The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and diluted with EA (200 mL). Washed with saturated brine (30.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. Purified by column chromatography (DCM:MeOH=100:1-50:1) to obtain a yellow solid. The solid was purified by reverse phase preparation (acetonitrile/water containing 0.1% formic acid = 0%-55%) to obtain the target compound (410 mg, yield 29.9%, Ret. time = 5.94 min, ee 96.7%, white solid). Chiral analysis method: Chiral column: DAICEL AD; mobile phase: A: Supercritical CO ₂ , B: MeOH (0.1% DEA); gradient: A 60%, B 40% for 8 min; flow rate: 2.0 mL/min; column temperature: 35° C. LC-MS (ESI) m/z 496.4 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ9.26 (s, 1H), 9.12 (d, J = 8.4Hz, 1H), 8.77 (s, 1H), 8.68 (s, 1H), 8.38 (s, 1H), 8.25 (s, 1H), 8.19 (d, J = 2.4Hz, 1H), 8.12 (s, 1H), 7. 95(s,1H),7.82(dd,J＝8.6,2.5Hz,1H),6.73(d,J＝8.6Hz,1H),5.26–5.18(m, 1H),5.09–5.02(m,1H),3.89(s,3H),1.58(d,J＝7.1Hz,3H),1.27(d,J＝6.2Hz ,6H).

Example 50: Synthesis of (R)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 50)

Step 1: Synthesis of 1-(6-isopropoxypyridin-3-yl)ethan-1-one

Under argon protection at 0°C, methylmagnesium bromide solution (3.0M in THF, 4.50mL, 13.5mmol) was added dropwise to a solution of 2-isopropoxy-5-cyanopyridine (730mg, 4.50mmol) in anhydrous tetrahydrofuran (20.0mL). The reaction mixture was stirred at 0°C for 2 hours and then continued to stir at room temperature for 16 hours. The reaction solution was quenched with 1.0M hydrochloric acid solution and the pH was adjusted to 9 with saturated sodium bicarbonate solution. It was extracted with EA (80.0mL×2). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure to obtain a crude product. The target compound (550mg, yield 68.2%, yellow oil) was obtained by column chromatography separation and purification (silica gel, PE:EA＝100:1-10:1). LC-MS(ESI)m/z 180.3[M+H] ⁺ .

Step 2: Synthesis of 1-(6-isopropoxypyridin-3-yl)ethan-1-one oxime

To a solution of 1-(6-isopropoxypyridin-3-yl)ethan-1-one (550 mg, 3.07 mmol) in ethanol (6.00 mL) was added hydroxylamine hydrochloride (427 mg, 6.14 mmol) and sodium acetate (503 mg, 6.14 mmol) in water (3.00 mL). The reaction mixture was stirred at 90°C for 2 hours. The reaction mixture was cooled and concentrated under reduced pressure. EA (100 mL) was added. The organic phase was separated and washed with saturated brine (15.0 mL × 2), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain the target compound (580 mg, yield 97.3%, light yellow solid). LC-MS (ESI) m/z 195.2 [M+H] ⁺ . ¹ H NMR (400MHz, DMSO-d ₆ ) δ11.17(s,3H),8.40–8.35(m,1H),7.94(dd,J＝8.7,2.5Hz,1H),6.78–6.71(m,1H),5.32–5.20(m,1H),2.13(s,3H),1.29(d,J＝6. 2Hz, 6H).

Step 3: Synthesis of 1-(6-isopropoxypyridin-3-yl)ethan-1-amine

At -10 ° C, nickel chloride hexahydrate (1.42 g, 5.97 mmol) was added to a solution of 1-(6-isopropoxypyridin-3-yl)ethan-1-one oxime (580 mg, 2.99 mmol) in methanol (15.0 mL), and then sodium borohydride (904 mg, 23.9 mmol) was slowly added. The reaction mixture was stirred at room temperature for 2 hours. Acetone (10.0 mL) was added to the reaction solution to quench the reaction. Concentrate under reduced pressure to obtain a crude product. The target compound (265 mg, yield 49.2%, black oil) was obtained by column chromatography separation and purification (DCM: MeOH = 20: 1-7: 1). ¹ H NMR (400MHz, MeOH-d ₄ ) δ8.06(d,J＝2.5Hz,1H),7.70(dd,J＝8.6,2.5Hz,1H),6.71(d,J＝8.6Hz,1H),5.21–5.14(m,1H),4.11–4.02(m,1H),1.40(d,J＝6.7 Hz, 3H), 1.31 (d, J = 6.2Hz, 6H).

Step 4: Synthesis of 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

At room temperature, 1-(6-isopropoxypyridin-3-yl)ethyl-1-amine (266 mg, 1.47 mmol) and DIEA (254 mg, 1.96 mmol) were added to a solution of CDI (318 mg, 1.96 mmol) in DMF (12.0 mL). After the reaction mixture was stirred at room temperature for 2 hours, 6-(1-methyl-1H-pyrazol-4-yl)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (320 mg, 0.984 mmol) was added. The reaction mixture was stirred at 70°C for 16 hours. After the reaction mixture was cooled to room temperature, it was diluted with EA (200 mL), washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was obtained by column chromatography separation and purification (DCM: MeOH = 100:1-30:1). The crude product was purified by liquid phase preparation (acetonitrile/water containing 0.05% formic acid) to obtain the target compound (45.0 mg, yield 9.24%, off-white solid). LC-MS (ESI) m/z 496.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ9.26(d,J＝1.3Hz,1H),9.12(d,J＝8.4Hz,1H),8.78–8.76(m,1H),8.68(s,1H),8.38(s,1H),8.26–8.24(m,1H),8.19(d,J＝2.3Hz,1H),8.12(s,1H),7 .96(d,J＝1.3Hz,1H),7.82(dd,J＝8.6,2.5Hz,1H),6.73(d,J＝8.5Hz,1H),5.26–5.18(m,1H),5.10–5.01(m,1H),3.89(s,3H),1.58(d,J＝7.0Hz,3H),1.27 (d, J=6.2Hz, 6H).

Step 5: Synthesis of (R)-4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide

The racemic 4-(3-cyano-6-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (45 mg dissolved in about 16 mL of methanol, injection volume 8.0 mL) was separated by Waters SFC150 (room temperature, 100 bar, 214 nm) and a 250*25mm 10μm Dr.maish Reprosil Chiral-OM (supercritical carbon dioxide: methanol, 45:55, 5.6 min, 100 mL/min) to give compound 50 (23.68 mg, white solid, Ret. time = 2.95 min, ee 100%) and compound 49 (18.47 mg, white solid, Ret. time = 5.94 min, ee 100%). The configuration and purity of the compound were confirmed by the chiral analysis method used in the synthesis of Example 49 above. LC-MS (ESI) m/z 496.1 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ9.26(d,J＝1.2Hz,1H),9.12(d,J＝8.5Hz,1H),8.80–8.75(m,1H),8.68(s,1H),8.38(s,1H),8.27–8.22(m,1H),8.19(d,J＝2.3Hz,1H),8.12(s,1H),7 .96(d,J＝1.3Hz,1H),7.82(dd,J＝8.6,2.5Hz,1H),6.73(d,J＝8.6Hz,1H),5.29–5.16(m,1H),5.15–4.96(m,1H),3.89(s,3H),1.58(d,J＝7.1Hz,3H),1.27 (d, J=6.2Hz, 6H).

Example 51: Synthesis of (S)-4-(3-cyano-6-(2-hydroxy-2-methylpropoxy)pyrazolo[1,5-a]pyridin-4- yl)-N-(1-(6-isopropoxypyridin-3-yl)ethyl)-1H-pyrazole-1-carboxamide (Compound 51)

At room temperature, (S)-phenyl(1-(6-isopropoxypyridin-3-yl)ethyl)carbamate (130 mg, 0.431 mmol) was added to a solution of 6-(2-hydroxy-2-methylpropoxy)-4-(1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridine-3-carbonitrile hydrochloride (120 mg, 0.360 mmol) and DIEA (0.119 mL, 0.719 mmol) in DMF (4.00 mL). The reaction mixture was stirred at 70°C for 16 hours. The reaction mixture was cooled to room temperature and diluted with EA (80.0 mL). It was then washed with saturated brine (15.0 mL×3), dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain a crude product. The crude product was obtained by separation and purification by silica gel column chromatography (dichloromethane: methanol = 100: 1-30: 1). The crude product was purified by reverse phase preparation (acetonitrile/water containing 0.01% formic acid) to obtain the target compound (85.1 mg, yield 47.0%, white solid). LC-MS (ESI) m/z 504.3 [M+H] ⁺ . ¹ H NMR (400 MHz, DMSO-d ₆ )δ9.10(d,J＝8.4Hz,1H),8.73(s,1H),8.70(d,J＝2.0Hz,1H),8.60(s,1H),8.23–8.21(m,1H),8.18(d,J＝2.4Hz,1H),7.81(dd,J＝8.6,2.5Hz,1H),7.50(d ,J＝2.0Hz,1H),6.73(d,J＝8.6Hz,1H),5.25–5.18(m,1H),5.08–4.99(m,1H),4.70(s,1H),3.87(s,2H),1.57(d,J＝7.1Hz,3H),1.27(d,J＝6.2Hz,6H),1 .22(s,6H).

Active Examples

Unless otherwise specified, the experimental materials, reagents, operations and methods used in the following active examples can be obtained from commercial channels or can be easily known or prepared based on existing technologies.

Activity Example 1: Kinase RET inhibition assay

The kinase RET inhibition assay was performed using a method similar to that described in the literature (Vivek Subbiah, J.F.G., Precision Targeted Therapy with BLU-667 for RET-Driven Cancers. Cancer Discov, 2018.8(7):836-849). The Caliper Mobility Shift Assay method was used to detect the inhibitory effect of the compound on the kinase RET. The final concentration of the compound test was 1000 nM, 3-fold serial dilution, a total of 10 concentrations, and duplicate well detection.

The test compound was dissolved in 100% DMSO (Sigma, D8418-1L, SHBG3288V) to prepare a 10mM stock solution, which was stored in a nitrogen cabinet away from light. 1× Kinase buffer was prepared, and the compound concentration gradient was prepared as follows: the starting test concentration of the test compound was 1000nM, and it was diluted 3 times in a 384-well plate (Corning, 3573, 12619003) with DMSO, a total of 10 concentrations, and the final concentrations were 1000, 333, 111, 37, 12.3, 4.12, 1.37, 0.457, 0.152, and 0.0508nM, and then 250nl was transferred to the 384 reaction plate using Echo550 (Labcyte, model: Echo 550) for use, and 250nl 100% DMSO was added to the negative control wells and positive control wells respectively. Use 1×Kinase buffer to prepare a kinase solution of RET (Carna, Cat. No. 08-159, Batch No. 13CBS-0134E) at 2.5 times the final concentration (final concentration is 1 nM). Add 10 μL of 2.5 times the final concentration of the kinase solution to the compound wells and positive control wells respectively; add 10 μL of 1×Kinase buffer to the negative control wells.

Centrifuge the reaction plate at 1000 rpm (Eppendorf, model: 5430) for 30 seconds, shake the reaction plate and incubate at room temperature for 10 minutes. Prepare a mixed solution of 25 times the final concentration (final concentration is 16 μM) of ATP and 15 times the final concentration (final concentration is 3 μM) of Kinase substrate 2 (GL, catalog number 112394, batch number P171207-MJ112394) with 1×Kinase buffer, and add 15 μL of the mixed solution to each well to start the reaction. Centrifuge the 384-well plate at 1000 rpm for 30 seconds, shake and mix, and incubate at room temperature for 60 minutes. Add 30 μL of EDTA-containing stop detection solution to stop the kinase reaction, centrifuge at 1000 rpm for 30 seconds, shake and mix. Read the conversion rate using a microplate reader (Perkin Elmer, model: Caliper EZ ReaderⅡ).

The calculation is done using the following formula:

% Inhibition = (conversion%_max-conversion%_sample)/(conversion%_sample-conversion%_min)*100

Wherein: "Conversion%_sample" is the conversion rate reading of the sample; "Conversion%_min" is the mean of the negative control wells, representing the conversion rate reading of the wells without enzyme activity; "Conversion%_max" is the mean of the positive control wells, representing the conversion rate reading of the wells without compound inhibition.

The log value of the concentration was used as the X-axis and the percentage inhibition rate was used as the Y-axis. The log (inhibitor) vs. response-Variable slope of the analysis software GraphPad Prism 5 was used to fit the dose-effect curve.

Calculation formula: Y = Bottom + (Top-Bottom) / (1 + 10^((LogIC50-X)*HillSlope))

Thus, the _IC50 value of each compound on the enzyme activity was obtained.

Table 1 RET kinase assay results

Activity Example 2: Cell proliferation assay

The inhibitory effect of the compounds of the present invention on cell proliferation was tested using the CellTiter-Glo ^™ live cell detection kit. The kit uses luciferase as a detection substance. Luciferase requires the participation of ATP in the luminescence process. CellTiter-Glo ^™ reagent is added to the cell culture medium, and the luminescence value is measured. The light signal is proportional to the amount of ATP in the system, and ATP is positively correlated with the number of live cells, thereby determining the cell proliferation activity.

Cell culture and inoculation: cells in the logarithmic growth phase (Ba/F3 KIF5B-RET, obtained from Kangyuan Bochuang, stably transfected in RPMI1640 (Hyclone, SH30027.01) + 10% FBS (GBICO, 10099-141)) were harvested and counted using a platelet counter. Cell viability was detected by trypan blue exclusion to ensure that the cell viability was above 90%. 90 μL of cell suspension was added to a 96-well transparent flat-bottom black wall plate (Thermo, 165305) and the cell concentration was adjusted to 3000/well/90ul. The cells in the 96-well plate were cultured overnight at 37°C, 5% CO ₂ , and 95% humidity (Thermo, Model 3100 Series).

First, DMSO was used as a solvent to prepare a 10000 μM stock solution of the test compound, which was then diluted 100 times with PBS to prepare a solution with a 10-fold final concentration, with the highest concentration being 100 μM. 10 μL of the test compound solution was added to each well of a 96-well plate seeded with cells, and the solution was diluted 10 times to reach a final concentration of 10 μM. The test compound was diluted 3 times in series starting from 10 μM, with a total of 9 concentrations, each with 3 replicates. The 96-well plate with the test compound and cells added was placed at 37°C, 5% CO ₂ , and 95% humidity for 72 hours before CellTiter-Glo analysis.

Thaw CellTiter-Glo Reagent ( Luminescent Cell Viability Assay, Promega, G7572) and equilibrate the cell plate to room temperature for 30 minutes. Add an equal volume of CellTiter-Glo solution to each well and shake on an orbital shaker for 5 minutes to lyse the cells. Place the cell plate at room temperature for 20 minutes to stabilize the luminescence signal, and read the luminescence value using a SpectraMax multi-label microplate reader (MD, M3).

The data were analyzed using GraphPad Prism 7.0 software, and the dose-effect curves were fitted using nonlinear S-curve regression, from which the _IC50 values were calculated.

Cell survival rate (%) = (Lum _{test drug} - Lum _{culture medium control} ) / (Lum _{cell control -} Lum _{culture medium control} ) × 100%

Table 2 Cell proliferation assay results

Activity Example 3: Metabolic stability experiment of human and mouse liver microsomes

According to the standard method of in vitro metabolic stability study conventional in the art, for example, the method described in (Kerns, Edward H. and Di Li (2008). Drug-like Properties: Concepts, Structure Design and Methods: from ADME to Toxicity Optimization. San Diego: Academic Press; Di, Li et al., Optimization of a Higher Throughput Microsomal Stability Screening Assay for Profiling Drug Discovery Candidates, J. Biomol. Screen. 2003, 8 (4), 453.), the hepatic microsomal metabolic stability test of the compounds of the present invention is similarly performed as follows.

Liver microsomes (protein concentration of 0.56 mg/mL) were added with 1 μM compound working solution (10 mM DMSO stock solution was diluted to 100 μM with 100% acetonitrile, organic phase content: 99% ACN, 1% DMSO), pre-incubated at 37°C for 10 min, and then the reaction was started by adding cofactor (NADPH) (prepared with magnesium chloride solution). After incubation for an appropriate time (such as 5, 10, 20, 30 and 60 minutes), samples were taken and an appropriate stop solution (ice acetonitrile (i.e., acetonitrile at 4°C) containing 200 ng/mL tolbutamide and 200 ng/mL labetalol) was added to terminate the reaction.

Sample treatment (n=1): add appropriate samples, vortex and centrifuge at high speed, take the supernatant, and use HPLC-MS/MS to detect the substrate. The peak area at the 0min time point is taken as 100%. The peak area at other time points is converted to the percentage residual amount, and the natural logarithm of the percentage residual amount at each time point is plotted against the incubation time, and the slope (-k) is calculated. Then, according to the intrinsic clearance rate (Clint) = (k*incubation fluid volume)/liver microsome mass, Clint (uL/min/mg) and compound half-life (T1/2, min) are calculated. The results are shown in Table 3.

Table 3. Results of metabolic stability experiments on human and mouse liver microsomes

Activity Example 4: Pharmacokinetic (PK) Determination of the Compounds of the Invention in Mice

The PK assay for each compound was performed as follows: 6 CD-1 mice (from Shanghai Lingchang Biotechnology Co., Ltd.) were divided into two groups, 3 mice in each group. One group was administered intravenously (IV) at a dose of 1 mg/kg, with a solvent of 5% DMSO/95% (20% Captisol); the other group was administered orally (Po) by gavage at a dose of 5 mg/kg, with a solvent of 1% HPMC. Blood was collected from the saphenous vein of the lower leg at 0, 0.083, 0.25, 0.5, 1, 2, 4, 6, 8, and 24 h after administration in each group. About 40 μL of blood was collected into an anticoagulant tube containing EDTA-K2. After the collection was completed, the blood collection tube was quickly inverted at least 5 times to ensure uniform mixing, and then placed on ice. The blood collected at each time point was centrifuged at 4°C and 8000 rpm for 5 minutes to obtain plasma. Another 1.5 mL centrifuge tube was labeled with the compound name, animal number, and time point, and the plasma was transferred to the tube. The plasma was stored at -80°C until analysis.

The concentration of the compound in plasma was determined by UPLC-MS/MS, and the pharmacokinetic parameters were calculated using Phoenix WinNolin 6.4 pharmacokinetic software.

The specific experimental results are as follows, which show that the compound has good drug absorption and pharmacokinetic advantages.

Table 4. In vivo PK results of the compounds in the examples

Table 5. In vivo PK results of the compounds in the examples

Those skilled in the art will appreciate that the above description is exemplary and illustrative in nature and is intended to illustrate the present invention and its preferred embodiments. Through routine experimentation, the skilled person will appreciate that obvious modifications and changes can be made without departing from the spirit of the present invention. All such modifications within the scope of the appended claims are intended to be included therein. Therefore, the present invention is intended to be defined not by the above description but by the following claims and their equivalents.

All publications cited in this specification are herein incorporated by reference.

Claims (32)

1. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof:

wherein:

r ₁ is selected from cyano;

R ₂ is selected from the group consisting of 5-6 membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from N, O or S, C ₁-C₆ alkyl, C ₁-C₆ alkoxy, and C ₁-C₆ alkylthio, R ₂ is optionally substituted with 1, 2, or 3 groups independently selected from: halogen, hydroxy and C ₁-C₆ alkyl;

R ₃ is selected from hydrogen, halogen, and C ₁-C₆ alkyl;

R ₄ is selected from phenyl, 5-6 membered heteroaryl containing 1, 2, or 3 heteroatoms independently selected from N, O or S, 5-6 membered heterocycloalkyl, 5-6 membered heterocycloalkenyl, 5-6 membered heterocycloalkyloxy, 5-6 membered heterocycloalkenyloxy, C ₁-C₆ alkyl, C ₁-C₆ alkoxy, and C ₁-C₆ alkylthio, R ₄ is optionally substituted with 1, 2, or 3 groups independently selected from: halogen, hydroxy and C ₁-C₆ alkyl;

R ₅ is selected from halogen, C ₁-C₆ alkyl, C ₁-C₆ alkoxy, and C ₁-C₆ alkylthio;

Ring a is selected from phenylene, a 5-9 membered heteroaryl group comprising 1,2, or 3 heteroatoms independently selected from N, O or S, C ₃-C₈ cycloalkylene, C ₃-C₈ cycloalkenylene, a 3-8 membered heterocycloalkylene group comprising 1,2, or 3 heteroatoms independently selected from N, O or S, and a 3-8 membered heterocycloalkenylene ring comprising 1,2, or 3 heteroatoms independently selected from N, O or S;

Ring B is selected from phenyl and 5-6 membered heteroaryl comprising 1, 2 or 3 heteroatoms independently selected from N, O or S;

m is 0, 1, 2 or 3; and is also provided with

N is 0, 1, 2 or 3.

2. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 1, wherein R ₂ is selected from a 5-membered heteroaryl group comprising 1,2 or 3 heteroatoms independently selected from N, O or S, optionally substituted by C ₁-C₆ alkyl, and a C ₁-C₆ alkoxy group optionally substituted by hydroxy.

3. A compound of formula (I), a stereoisomer, or a pharmaceutically acceptable salt thereof according to claim 2, wherein R ₂ is selected from pyrrolyl, furanyl, thienyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, or pyrazolyl optionally substituted with C ₁-C₆ alkyl and C ₁-C₆ alkoxy optionally substituted with hydroxy.

4. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 3, wherein R ₂ is selected from methyl-substituted pyrazolyl or hydroxy-substituted C ₁-C₆ alkoxy.

5. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 4, wherein R ₂ is

6. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 2, wherein R ₃ is selected from hydrogen and C ₁-C₆ alkyl.

7. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 6, wherein R ₃ is selected from hydrogen and C ₁-C₃ alkyl.

8. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 7, wherein R ₃ is hydrogen or methyl.

9. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 2,

Wherein the method comprises the steps of

R ₄ is selected from the group consisting of 5 membered heteroaryl, 5-6 membered heterocycloalkyl, 5-6 membered heterocycloalkyloxy, C ₁-C₆ alkyl and C ₁-C₆ alkoxy containing 1,2 or 3 heteroatoms independently selected from N, O or S, R ₄ is optionally substituted with 1,2 or 3 groups independently selected from: halogen and C ₁-C₆ alkyl.

10. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 9, wherein R ₄ is selected from pyrazolyl, pyrrolidinyl, tetrahydropyranyloxy, morpholinyl, tetrahydrofuranyloxy, C ₁-C₆ alkyl and C ₁-C₆ alkoxy, R ₄ being optionally substituted by halogen.

11. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 10, wherein R ₄ isPyrrolidin-1-yl, methoxy, ethoxy, isopropoxy, trifluoromethoxy or CF ₃.

12. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 2, wherein R ₅ is selected from C ₁-C₃ alkyl.

13. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 12, wherein R ₅ is selected from methyl, ethyl and propyl.

14. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 13, wherein R ₅ is selected from methyl.

15. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 2 wherein,

M is 0 or 1; and/or

N is 0 or 1.

16. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 15, wherein m is 1 and/or

N is 0 or 1.

17. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 2, wherein

Ring a is selected from phenylene, 5-6 membered heteroarylene containing 1,2, or 3 heteroatoms independently selected from N, O or S, C ₃-C₈ cycloalkylene, C ₃-C₈ cycloalkylene, 3-8 membered heterocycloalkylene containing 1,2, or 3 heteroatoms independently selected from N, O or S, and 3-8 membered heterocycloalkenylene containing 1,2, or 3 heteroatoms independently selected from N, O or S.

18. A compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 17, wherein ring a is selected from phenylene, a5 membered heteroaryl group comprising 1, 2 or 3 heteroatoms independently selected from N, O or S, C ₃-C₆ cycloalkylene, C ₃-C₆ cycloalkenylene, a 3-6 membered heterocycloalkylene group comprising 1, 2 or 3 heteroatoms independently selected from N, O or S and a 3-6 membered heterocycloalkenylene group comprising 1, 2 or 3 heteroatoms independently selected from N, O or S.

19. A compound of formula (I), a stereoisomer, or a pharmaceutically acceptable salt thereof as claimed in claim 17, wherein ring a is selected from phenylene, pyrrolylene, furanylene, thiophenylene, imidazolylene, furazanyl, oxazolylene, oxadiazolylene, oxazolylene, isoxazolylene, thiazolylene, isothiazolylene, pyrazolylene, thiadiazolylene, triazolylene, pyridylene, pyrazinylene, pyridazinylene, pyrimidinylene, triazinylene, azetidinylene, pyrrolidinylene, pyrrolinyl, cyclobutylene, cyclopentyl, cyclohexyl, cycloheptylene, piperazinylene, piperidinylene, tetrahydropyridinyl, 3, 6-diaza-bicyclo [3.1.1] heptylene, 3-aza-bicyclo [3.2.1] octylene, and 1, 4-diazacycloheptylene.

20. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 19, wherein ring a is selected from pyrazolylene, thiadiazolylene, pyrrolidinylene, pyrrolinyl, cyclohexylene, piperazinylene, piperidinylene, tetrahydropyridinylene, 3, 6-diaza-bicyclo [3.1.1] heptylene, 3-aza-bicyclo [3.2.1] octylene and 1, 4-diazacycloheptylene.

21. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof as claimed in claim 19, wherein ring a is selected from

22. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 2, wherein ring B is selected from phenyl, pyrrolyl, furanyl, thienyl, imidazolyl, furazanyl, oxazolyl, oxadiazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, thiadiazolyl, triazolyl, pyridinyl, pyrazinyl, pyridazinyl, pyrimidinyl and triazinyl rings.

23. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to any one of claims 22, wherein ring B is a pyridinyl ring.

24. A compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to claim 1, wherein the groupSelected from the group consisting of

25. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 1 wherein the compound of formula (I) has the structure of formula (Ia),

Wherein R ₁、R₂、R₃、R₄、R₅, m, n and A each have the meaning as defined in claim 1.

26. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 1 wherein the compound of formula (I) has the structure of formula (Ib),

Wherein R ₁、R₂、R₃、R₄、R₅, n and A each have the meaning as defined in claim 1.

27. The compound of formula (I), stereoisomer or pharmaceutically acceptable salt thereof according to claim 1, wherein the compound of formula (I) has the structure of formula (Ic),

Wherein R ₂、R₃、R₄、R₅, n and A each have the meaning as defined in claim 1.

28. A compound of formula (I) according to claim 1 selected from the following:

Or a stereoisomer or pharmaceutically acceptable salt thereof.

29. A pharmaceutical composition comprising a compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof, according to any one of claims 1-28 and a pharmaceutically acceptable excipient; the pharmaceutical composition optionally further comprises a further therapeutically active ingredient suitable for use in combination with a compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 28.

30. A pharmaceutical combination comprising a compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to any one of claims 1 to 28 and an additional active agent.

31. Use of a compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to any one of claims 1-28 or a pharmaceutical composition according to claim 29 for the manufacture of a medicament for the prevention or treatment of a disease associated with RET.

32. Use of a compound of formula (I), a stereoisomer or a pharmaceutically acceptable salt thereof according to any one of claims 1-28 or a pharmaceutical composition according to claim 29 for the manufacture of a medicament for the prevention or treatment of a RET related disease selected from the group consisting of tumor or Irritable Bowel Syndrome (IBS), tumor selected from the group consisting of non-small cell lung cancer, papillary thyroid cancer, medullary thyroid cancer, differentiated thyroid cancer, recurrent thyroid cancer, refractory differentiated thyroid cancer, endocrine tumor 2A or 2B, pheochromocytoma, parathyroid hyperplasia, breast cancer, colorectal cancer, papillary renal cell carcinoma, gastrointestinal mucosal ganglioma, pancreatic ductal adenocarcinoma, multiple endocrine tumor, testicular cancer, chronic monocytic leukemia, salivary gland cancer, ovarian cancer or cervical cancer.