CN105294478B - Diastereoisomer of aliskiren, preparation method and application thereof - Google Patents

Abstract

The invention relates to a diastereoisomer of Aliskiren with a (2S, 4R, 5R, 7S) configuration, and the molecular structure of the diastereoisomer is shown as a formula 4R, 5R-1. The invention also relates to the use of said aliskirenA method for the preparation of diastereomers of the (2S, 4R, 5R, 7S) configuration, and their use for detecting the purity of aliskiren and salts thereof, for detecting the content of optical isomers in aliskiren and salts thereof, and for quality control in the production or preparation of aliskiren and salts thereof.

Description

A diastereoisomer of Aliskiren, its preparation method and use

technical field

The present invention relates to a diastereoisomer, specifically, the present invention relates to a diastereoisomer of (2S, 4R, 5R, 7S) configuration of aliskiren. The present invention also relates to the preparation method and application of the (2S, 4R, 5R, 7S) configuration diastereoisomer of the aliskiren.

Background technique

Aliskiren (1) is a new type of non-peptide direct renin inhibitor, the relevant pharmacodynamics, pharmacokinetics and clinical research results are in Drugs of the Future, Vol.26, No12, pp1139-1143 ( 2001) and other journals have detailed statements, which are characterized by reducing the activity of renin in a dose-dependent manner, reducing the generation of angiotensin II, the main active peptide of the renin-angiotensin system (RAS), from the source, Effectively lower blood pressure levels in patients with mild to moderate hypertension. Aliskiren was first launched in the United States in March 2007 in the form of its fumarate, under the trade name TEKTURNA ^TM . It has been proved by clinical studies to have a good antihypertensive effect. New drugs for blood pressure.

The existing patent documents US5,559,111, EP0678503, WO02/02508, WO2007/045420, WO2011/019789 and US7,009,078 have reported the synthesis method of aliskiren. For example, the patent WO02/02508 adopts the following synthetic route:

Patent WO2007/045420 adopts another synthetic route:

The key point in the synthesis of Aliskiren is to adopt the method of asymmetric synthesis to construct the four chiral centers in the molecule, so as to obtain the S configuration of the 4-position hydroxyl group, the S configuration of the 5-position amino group, and the Propyl is the single optical enantiomer of the S configuration. Wherein, for the construction process of the 4-hydroxyl and 5-amino chiral centers, all the above-mentioned known synthetic methods have been solved. In the synthesis method shown in the above-mentioned patent WO02/02508, the double bond of compound 7 is subjected to stereoselective addition reaction with hypobromous acid to obtain a compound of (3S, 5R, 1'S, 3'S) configuration 4, and further stereospecific reaction to obtain Aliskiren; as in the synthetic method shown in the above-mentioned patent WO2007/045420, the double bond of compound 16 is subjected to stereoselective addition reaction with hypobromous acid, and further Stereospecific reaction to obtain Aliskiren.

As we all know, no matter what kind of chemical reaction is used in the synthesis method to construct the 4-position hydroxyl and 5-position amino chiral center, its stereoselectivity cannot be 100%, and it is more or less possible to produce 4-position R and 5-position R The isomer of the configuration, so that the isomer of the (2S, 4R, 5R, 7S) configuration is more or less mixed in when the Aliskiren of the (2S, 4S, 5S, 7S) configuration is finally generated, that is Compound 4R, 5R-1. The configurations of the 2 and 7 positions of this isomer are consistent with the target molecule Aliskiren, only the configurations of the 4 and 5 positions are inconsistent.

In addition, the 4-position hydroxyl group and the 5-position amino group have relatively active chemical reaction properties. How to maintain the configuration of the 4-position hydroxyl group and the 5-position amino group in the process of subsequent chemical reactions, long-term storage, and processing into pharmaceutical preparations? Change is also an important factor to be considered in the process of preparing Aliskiren.

Like other chemically synthesized drugs, the purity of the active pharmaceutical substance (API) is a key indicator for the commercial utilization of Aliskiren. Impurities called related substances, such as starting materials, reaction intermediates, by-products, and degradation products, may be introduced during the production process of API. Some of these impurities may be harmful to patients. The International Conference on Drug Administration (ICH) requires that the API must have sufficient purity, and the content of impurities must be controlled within the limits specified in the drug quality standards. For a single optical enantiomer drug such as Aliskiren, it has 4 chiral centers and theoretically has 15 optical isomers. The chemical molecular formula of these isomers is the same as that of Aliskiren, and the physical and chemical properties are also the same. Or similar, but their efficacy and toxicity to the human body after entering the human body may be quite different from that of aliskiren. ICH requires these possible optical isomers to be studied as impurities to ensure the efficacy and toxicity of the drug. For example, in the ICHQ7A guidelines for API production, standardized requirements are put forward for raw materials and production conditions. In a specific stage of API production, impurities in intermediates or finished products need to be inspected, especially by high performance liquid chromatography (HPLC). )Law. The HPLC method is used to test the content of a certain impurity in the sample, usually using the external standard method, or the self-control method with a correction factor, and the prerequisite is to obtain the reference substance of the impurity to be tested.

To sum up, in order to ensure the consistency of efficacy and minimum toxicity of aliskiren marketed drugs, the best method is to use high performance liquid chromatography to control the content of impurities such as 4R and 5R-1. For example, the external standard method or the self-control method with a correction factor requires 4R and 5R-1 compounds as reference substances. However, so far, no reports about compounds 4R, 5R-1 have been found. Therefore it is necessary to develop a preparation method of compound 4R, 5R-1 to obtain a reference substance, and a method for analyzing the content of this isomer, so as to be used for the optical purity inspection of Aliskiren or its salt, and then for Aliskiren or Quality control of its salt.

Contents of the invention

The first aspect of the present invention relates to a diastereoisomer of (2S, 4R, 5R, 7S) configuration of aliskiren, its molecular structure is shown in formula 4R, 5R-1, and its chemical name is: (2S , 4R, 5R, 7S)-5-amino-N-(2-carbamoyl-2-methylpropyl)-4-hydroxyl-2-isopropyl-7-(4-methoxy-3- (3-methoxypropoxy)benzyl)-8-methylnonanamide.

The second aspect of the present invention relates to the preparation method of the (2S, 4R, 5R, 7S) configuration diastereomers of Aliskiren in the first aspect of the present invention, which comprises the following steps:

a) The following compound (3S, 5R, 1′S, 3′S)-4 is used as the starting material for synthesis, and its chemical name is: (3S, 5R)-5-[(1S, 3S)- 1-bromo-3-[[4-methoxy-3-(3-methoxypropoxy)phenyl]methyl]-4-methylpentyl]dihydro-3-isopropyl-2 (3H)-furanone;

b) react compound (3S, 5R, 1'S, 3'S)-4 with sodium azide to obtain compound (3S, 5R, 1'R, 3'S)-5 as shown below;

c) react compound (3S, 5R, 1'R, 3'S)-5 with 3-amino-2,2-dimethylpropylamine to obtain compound 4R, 5R-2 as shown below;

d) Compounds 4R, 5R-2 are obtained by catalytic hydrogenation to obtain compounds of formula 4R, 5R-1, wherein the method of palladium carbon catalytic hydrogenation is preferred;

The preparation method according to any one of the second aspect of the present invention is characterized by one or more of the following items (1) to (12):

(1) In step b), the solvent of the compound (3S, 5R, 1′S, 3′S)-4 solution is selected from N,N-dimethylformamide, tripropylene glycol, pyridine, N-methylpyrrolidone, etc. , preferably tripropylene glycol;

(2) In step b), the molar ratio of compound (3S, 5R, 1'S, 3'S)-4 to sodium azide is 1:3 to 1:10, preferably 1:5;

(3) In step b), the reaction temperature is 60-100°C, preferably 80-90°C;

(4) In step b), after the reaction, add an organic amine, such as diethylamino-1-propylamine, and add water and a solvent for extraction, wherein the solvent is selected from methyl tert-butyl ether , dichloromethane, ethyl acetate, etc.; the organic layer was washed with dilute hydrochloric acid, saturated sodium bicarbonate, and brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by silica gel column chromatography to obtain compound (3S, 5R, 1 'R,3'S)-5;

(5) In step c), the reaction solvent is selected from methyl tert-butyl ether, tetrahydrofuran, N-methylpyrrolidone, chloroform, etc., preferably methyl tert-butyl ether;

(6) In step c), an organic base is added to the reaction mixture, wherein the organic base is selected from pyridine, 2-hydroxypyridine, triethylamine, amantadine, etc., preferably 2-hydroxypyridine;

(7) In step c), the reaction temperature is 40-110°C, preferably 60-100°C, more preferably 70-90°C;

(8) In step c), after the reaction is completed, water and a solvent are added for extraction operation, wherein the solvent is selected from methyl tert-butyl ether, dichloromethane, ethyl acetate, etc.; the organic layer is concentrated after drying , the residue was purified by silica gel column chromatography to obtain compound 4R, 5R-2;

(9) In step d), the palladium carbon is palladium carbon containing 5% to 10% palladium;

(10) In step d), the solvent of compound 4R, 5R-2 is selected from methyl tert-butyl ether, ethanol, methanol, tetrahydrofuran, ethyl acetate, ethyl isopropyl ester, dichloromethane, preferably methanol, tetrahydrofuran ;

(11) In step d), wherein the pressure of the catalytic hydrogenation reaction is 1-10 bar, preferably 1-3 bar;

(12) In step d), filter after the catalytic hydrogenation reaction is completed, add saturated sodium bicarbonate solution and brine to the filtrate successively for extraction operation, the organic layer is concentrated after drying, and the residue is purified by column chromatography to obtain compounds 4R, 5R-1 .

In an embodiment of the present invention, compound (3S, 5R, 1'S, 3'S)-4 as a starting material is prepared according to the method described in Example C1 in patent WO02/02508.

In an embodiment of the present invention, sodium azide with a molar ratio of 1:3 to 1:10 is added to the solution of compound (3S, 5R, 1'S, 3'S)-4, preferably 1 : 5, wherein said solvent can be selected from N,N-dimethylformamide, tripropylene glycol, pyridine, N-methylpyrrolidone, etc., preferably tripropylene glycol, and the reaction temperature is 60～100°C, preferably 80～90°C , react for 48 to 72 hours, add water and a solvent for extraction operation, wherein the solvent is selected from methyl tert-butyl ether, dichloromethane, ethyl acetate, etc., the organic layer is concentrated after drying, and the residue is subjected to The compound (3S, 5R, 1'R, 3'S)-5 was purified by silica gel column chromatography.

In an embodiment of the present invention, an organic base is added to the reaction system of compound (3S, 5R, 1'R, 3'S)-5 and compound 6, wherein said organic base is selected from pyridine, 2-hydroxypyridine , triethylamine, amantadine, etc., preferably 2-hydroxypyridine, wherein the reaction solvent is selected from methyl tert-butyl ether, tetrahydrofuran, N-methylpyrrolidone, chloroform, etc., preferably methyl tert-butyl ether, and the reaction temperature can be Keep it in the range of 40-110°C, preferably 60-100°C, more preferably 70-90°C, add water and a solvent for extraction after the reaction is completed, wherein the solvent is selected from methyl tert-butyl ether , dichloromethane, ethyl acetate, etc.; the organic layer was dried and concentrated, and the residue was purified by silica gel column chromatography to obtain compounds 4R, 5R-2.

In an embodiment of the present invention, palladium carbon is added to the solution of compound 4R, 5R-2, and hydrogen is introduced into the solution for hydrogenation under pressure, wherein the palladium carbon is palladium carbon containing 5% to 10% palladium; wherein the The solvent is selected from methyl tert-butyl ether, ethanol, methanol, tetrahydrofuran, ethyl acetate, ethyl isopropyl ester, dichloromethane, etc., preferably methanol, tetrahydrofuran; wherein the pressure of the hydrogenation reaction is 1 to 10bar, preferably 1 ~3bar. After the reaction was completed, saturated sodium bicarbonate solution and brine were added successively for extraction, the organic layer was dried and concentrated, and the residue was purified by silica gel column chromatography to obtain compounds 4R, 5R-1.

The third aspect of the present invention also relates to a method for detecting the content of optical isomers in Aliskiren or its salts, the method adopts the external standard method in high performance liquid chromatography (HPLC), and any one of the first aspect of the present invention The (2S, 4R, 5R, 7S) configuration diastereoisomer of Aliskiren in the item is the reference substance, and the non-pair of (2S, 4R, 5R, 7S) configuration in Aliskiren or its salt is calculated. enantiomer content.

The method according to any one of the third aspect of the present invention, wherein the high performance liquid chromatography is characterized by one or more of the following items (1) to (5):

(1) The chromatographic column is a chiral column, preferably AD-H type, IC column or OJ-3R column, more preferably CHIRALPAK AD-H type chiral column (4.6mm×250mm, 5μm);

(2) The mobile phase is n-hexane-absolute ethanol (containing 0.2% to 0.5% diethylamine) (90-10 to 10-90) as the mobile phase, preferably n-hexane-absolute ethanol (containing 0.2% diethylamine Amine) (90:10);

(3) detection wavelength is 200～300nm, preferably 280nm;

(4) The flow rate is 0.5～1.5ml/min, preferably 1.0ml/min;

(5) The column temperature is 25-35°C, preferably 30°C.

In the present invention, the external standard method is a method well known in the art. In an embodiment of the present invention, the external standard method refers to:

1) Determination of the peak area containing a certain amount of compound 4R, the reference substance solution of 5R-1 with HPLC method;

2) Determination of the peak area of the compound 4R and 5R-1 contained in the sample of Aliskiren or its salt by HPLC;

3) Obtain the content of compound 4R and 5R-1 contained in the sample of aliskiren or its salt by calculating the ratio of the peak areas of 1) and 2).

In an embodiment of the present invention, the calculation method of compound 4R, 5R-1 content is: the compound in aliskiren hemifumarate

In the formula, _sample A is the peak area of compound 4R in the test solution, 5R-1;

W is _the sample amount (mg) that is compound 4R, 5R-1;

V _sample is the constant volume (ml) of the test solution;

A _pair is the peak area of compound 4R, 5R-1;

V is _the constant volume (ml) of compound 4R, 5R-1;

W _sample is the weighing amount (mg) of need testing solution.

The fourth aspect of the present invention relates to a method for detecting the content of optical isomers in aliskiren or its salts, the method adopts the self-control method of adding correction factors in high performance liquid chromatography, and uses any one of the first aspect of the present invention The (2S, 4R, 5R, 7S) configuration diastereoisomers of Aliskiren or its salts of the item is a calibration factor relative to the standard curve slope ratio of Aliskiren or its salts ( 2S, 4R, 5R, 7S) configuration diastereoisomer content.

The method according to any one of the fourth aspect of the present invention, wherein the high performance liquid chromatography is characterized by one or more of the following items (1) to (5):

(1) The chromatographic column is a chiral column, preferably AD-H type, IC column or OJ-3R column, more preferably CHIRALPAK AD-H type chiral column (4.6mm×250mm, 5μm);

(2) The mobile phase is n-hexane-dehydrated ethanol (containing 0.2%～0.5% diethylamine) (90～10 to 10～90), preferably n-hexane-dehydrated ethanol (containing 0.2% diethylamine) ( 90:10);

(3) detection wavelength is 200～300nm, preferably 280nm;

(4) The flow rate is 0.5～1.5ml/min, preferably 1.0ml/min;

(5) The column temperature is 25-35°C, preferably 30°C.

In the present invention, the self-control method of adding a correction factor is a method well known in the art. In an embodiment of the present invention, the self-control method of adding a correction factor refers to:

1) Using Aliskiren or its salt and compound 4R, 5R-1 as samples, prepare a series of solutions with different concentrations, draw a standard curve to obtain the slope, and calculate the correction factor of compound 4R, 5R-1 through the slope;

2) Determination of the peak area of Aliskiren and the peak area of compound 4R and 5R-1 contained in the sample of Aliskiren or its salt by HPLC;

3) Calculating the content of compound 4R, 5R-1 in aliskiren or its salt by using the correction factor.

In an embodiment of the present invention, the formula for calculating the content of compound 4R, 5R-1 is:

Aliskiren or its salt compound

In formula, A _4R5R-1 is the peak area of compound 4R, 5R-1 in need testing solution;

f _4R5R-1 is the correction factor of compound 4R, 5R-1 relative to Aliskiren or its salt;

A _pair is the peak area of Aliskiren or its salt in the control solution.

Where f _4R5R-1 = K _Aliskiren /K _{4R, 5R-1} ,

The calculation method of the K value is as follows: the concentration of a series of linear solutions is taken as the abscissa, and the peak area is taken as the ordinate to draw a standard curve to obtain the slope value K corresponding to the compound 4R, 5R-1, aliskiren and its salt.

In the present invention, the high performance liquid chromatography is a method well known in the art. In an embodiment of the present invention, the specific method of described high performance liquid chromatography is:

Prepare a solution of aliskiren and compound 4R, 5R-1 at a certain concentration, and perform high-performance liquid chromatography. The chromatographic conditions adopted are: the chromatographic column is a chiral column, preferably AD-H type, IC column or OJ-3R column, More preferably, it is CHIRALPAK AD-H type chiral column (4.6mm×250mm, 5μm); the mobile phase is n-hexane-absolute ethanol (containing 0.2%～0.5% diethylamine) (90～10 to 10～90), It is preferably n-hexane-absolute ethanol (containing 0.2% diethylamine) (90:10); the detection wavelength is 200-300nm, preferably 280nm; the flow rate is 0.5-1.5ml/min, preferably 1.0ml/min; The temperature is 25-35°C, preferably 30°C;

Separate injection and mixed injection respectively, the retention time of Aliskiren, the retention time of compounds 4R and 5R-1, and the resolution data of the two were obtained respectively.

In a specific embodiment of the present invention, wherein the retention time of Aliskiren is about 21.1min, the retention time of compound 4R, 5R-1 is about 25.1min, and the chromatographic peaks of the two can reach better under the liquid phase conditions. The separation, the resolution is 2.7.

The present invention also relates to the use of (2S, 4R, 5R, 7S) diastereomers of aliskiren in the first aspect of the present invention for detecting the content of optical isomers in aliskiren or its salts.

The present invention also relates to the use of the (2S, 4R, 5R, 7S) diastereomers of aliskiren in the first aspect of the present invention for quality control in the production or preparation of aliskiren or its salts.

The present invention also relates to the use of the (2S, 4R, 5R, 7S) diastereoisomers of aliskiren in the first aspect of the present invention for testing the purity of aliskiren or a salt thereof.

Description of drawings

Figure 1: ESI-MS spectra of compounds 4R, 5R-1

Figure 2: ¹ H-NMR spectra of compounds 4R, 5R-1

Figure 3: ¹³ C-NMR spectra of compounds 4R, 5R-1

Figure 4: ¹ H- ¹ HCOSY spectra of compounds 4R, 5R-1

Figure 5: HSQC profiles of compounds 4R, 5R-1

Figure 6: HPLC profile of Aliskiren hemifumarate

Figure 7: HPLC profiles of compounds 4R, 5R-1

Figure 8: HPLC spectrum of compound 4R, 5R-1 mixed with aliskiren hemifumarate

detailed description

Embodiments of the present invention will be described in detail below in conjunction with examples, but those skilled in the art will understand that the following examples are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all commercially available conventional products.

In the following examples, the concentration is in Carry out on R-200 type rotary evaporator; Described HPLC chromatogram is to measure on Shimadzu LC-10ATvp high-performance liquid chromatograph, wherein adopts the chiral chromatographic column of CHIRALPAK AD-H type; Mass spectrum is in JEOL AccuTOF CS Measure on (JMS T100CS) type mass spectrometer; NMR ¹ H spectrum and ¹³ C spectrum are measured on Bruker AVANCEIII400 type NMR apparatus; Described optical rotation is to measure on WZZ-2S type automatic polarimeter, wherein, sample The formula for calculating the specific rotation is:

In the formula, D is the D line of the sodium spectrum, l is the length of the measuring tube (dm), and α is the measured optical rotation.

Example 1 (3S, 5R)-5-[(1R, 3S)-1-azido-3-[[4-methoxy-3-(3-methoxypropoxy)phenyl]methanol Preparation of ]-4-methylpentyl]dihydro-3-isopropyl-2(3H)-furanone (3S, 5R, 1′R, 3′S-5)

The following compound (3S, 5R, 1′S, 3′S)-4 is used as the starting material for synthesis, and its chemical name is: (3S, 5R)-5-[(1S, 3S)-1- Bromo-3-[[4-methoxy-3-(3-methoxypropoxy)phenyl]methyl]-4-methylpentyl]dihydro-3-isopropyl-2(3H )-furanone. Compound (3S, 5R, 1'S, 3'S)-4 was prepared by the method described in Example C1 of patent WO02/02508.

The mixture of compound (3S, 5R, 1'S, 3'S)-4 (10.0g, 20mmol), sodium azide (6.5g, 100mmol) and tripropylene glycol (80ml) and water (53ml) at 80°C The reaction was stirred for 48 hours, the reaction mixture was cooled to room temperature, diethylamino-1-propylamine (8 ml) was added, and the reaction was stirred at room temperature for 3 hours. The reaction mixture was poured into water (200ml), extracted with methyl tert-butyl ether (3×200ml), and the organic phase was successively washed with 0.5N hydrochloric acid (200ml), 5% sodium bicarbonate (200ml), water (3 ×200ml), brine (200ml) for washing. The organic phase was dried with anhydrous sodium sulfate (200g), filtered and concentrated under reduced pressure, and purified by column chromatography (column chromatography silica gel, mobile phase: ethyl acetate/n-hexane=1:5) to obtain the compound shown below (3S, 5R, 1'R, 3'S-5) (6.9 g, 75.0% yield) was a pale yellow oil. ¹ H-NMR (400MHz, CDCl ₃ , ppm ^-1 ) δ: 0.82-0.98 (m, 12H), 1.44-1.50 (m, 2H), 1.68-1.83 (m, 3H), 1.96-2.22 (m, 5H) ), 2.47-2.53(m, 1H), 2.67-2.71(dd, 1H), 3.11-3.16(m, 1H), 3.30(s, 3H), 3.52(t, 2H), 3.78(s, 3H), 4.05 (t, 2H), 4.16-4.21 (m, 1H), 6.59-6.92 (m, 3H). ESI-MS (m/z): 484.3 (MNa ⁺ ).

Example 2 (2S, 4R, 5R, 7S)-N-(3-amino-2,2-dimethyl-3-oxypropyl)-5-azido-4-hydroxyl-2-isopropyl - Preparation of 7-(4-methoxy-3-(3-methoxypropoxy)benzyl)-8-methylnonanamide (4R, 5R-2)

(3S, 5R, 1'R, 3'S-5) (2.0g, 4.3mmol), 3-amino-2,2-dimethylpropanamide (2.5g, 22mmol), 2-hydroxypyridine (0.5 g, 5.2mmol), triethylamine (0.3g) and methyl tert-butyl ether (25ml) were mixed, stirred and refluxed to dissolve. The bath temperature was 80-90°C, stirred and reacted for 20 hours, evaporated the solvent under reduced pressure, added dichloromethane (30ml) and water (25ml) and stirred to dissolve, the aqueous phase was extracted twice with dichloromethane (15ml), and the organic phases were combined. And after washing with water (15ml) for 3 times, drying with anhydrous sodium sulfate and evaporating to dryness to obtain an oily substance, the oily substance was purified by silica gel column chromatography (mobile phase: ethyl acetate/petroleum ether=1/1) to obtain the following Compound 4R, 5R-2 (1.9 g, 78.3% yield) was shown as a colorless oil. ¹ H-NMR (400MHz, CDCl ₃ , ppm ^-1 ) δ: 0.88-0.98 (m, 12H), 1.20 (s, 6H), 1.44-1.63 (m, 3H), 1.69-1.93 (m, 5H), 2.05-2.31(m, 4H), 2.65-2.70(dd, 1H), 3.02-3.05(m, 1H), 3.34-3.46(m, 6H), 3.56(t, 2H), 3.82(s, 3H), 4.09 (t, 2H), 5.62 (brs, 1H), 6.05 (brs, 1H), 6.49 (brs, 1H), 6.70-6.79 (m, 3H). ESI-MS (m/z): 578.3 (MH ⁺ ).

Example 3 (2S, 4R, 5R, 7S)-5-amino-N-(2-carbamoyl-2-methylpropyl)-4-hydroxyl-2-isopropyl-7-(4-methyl Preparation of Oxy-3-(3-methoxypropoxy)benzyl)-8-methylnonanamide (4R, 5R-1)

The 4R, 5R-2 compound (1.4 g, 2.4 mmol) obtained in Example 2 was dissolved in methanol (50 ml), and palladium carbon (10%, 0.3 g) was added to the solution. Hydrogen was introduced into the reaction solution, and the hydrogen pressure was kept at 2.0 bar and stirred overnight. The reaction mixture was filtered, and saturated sodium bicarbonate solution and brine were successively added to the filtrate for extraction. The organic layer was dried and concentrated, and the obtained residue was purified by silica gel column chromatography (mobile phase: ethanol/ethyl acetate=1/1 ), the solvent was evaporated to dryness under reduced pressure to give 4R, 5R-1 (0.9 g, 69.0% yield) as a white solid.

Measure the optical rotation of the obtained compounds 4R and 5R-1: take about 0.2g of this product, weigh it accurately, put it in a 25ml measuring bottle, add ethanol to dissolve and dilute to the mark, and shake well to obtain the test solution. Take the test solution and measure the optical rotation on the automatic polarimeter, repeat the reading 3 times, and take the arithmetic mean value. The results of the optical rotation of the measured compounds 4R, 5R-1 and Aliskiren (prepared and provided by China Resources Double Crane Pharmaceutical Co., Ltd. according to the method described in Example G1 in the patent US7,009,078) are shown in Table 1 Show.

Table 1

According to the calculation formula of specific rotation, the specific rotation of compound 4R and 5R-1 is [α] _D ²⁰ =+22.9° (ethanol, C=8.33mg/ml); as a reference, the specific rotation of Aliskiren It is [α] _D ²⁰ = -11.4° (ethanol, C = 8.21g/m1).

For the obtained compound 4R, 5R-1, mass spectrometry (Fig. 1), proton nuclear magnetic resonance spectrum (Fig. 2), carbon spectrometry (Fig. 3), ¹ H- ¹ HCOSY spectrum (Fig. 4), HSQC spectrum (Fig. 5) were carried out measurement, it was found that:

1H-NMR (400MHz, CDCl3, ppm-1) δ: 0.86-0.99 (m, 12H), 1.04-1.07 (m, 1H), 1.20 (s, 6H), 1.47-1.48 (m, 1H), 1.58- 1.88(m, 5H), 2.00-2.23(m, 4H), 2.48-2.50(m, 1H), 2.64-2.69(dd, 1H), 3.10-3.15(m, 1H), 3.33-3.40(m, 5H) ), 3.57(t, 2H), 3.83(s, 3H), 4.09(t, 2H), 5.75(brs, 1H), 6.45(brs, 1H), 6.55(brs, 1H), 6.67-6.80(m, 3H).

13C-NMR (400MHz, CDCl3, ppm-1) δ: 17.8, 19.7, 20.1, 20.2, 24.0, 24.2, 29.1, 29.6, 30.7, 34.2, 35.2, 36.6, 42.8, 43.1, 47.1, 51.7, 54.1, 56.0, 58.6, 66.1, 69.3, 73.8, 111.8, 114.5, 121.3, 134.2, 147.6, 148.2, 176.4, 179.7.

ESI-MS (m/z): 552.4 (MH ⁺ ), 574.4 (MNa ⁺ ).

The results of the ¹ H- ¹ HCOSY test are shown in Figure 4, and the results of the HSQC test are shown in Figure 5. The above results are consistent with the chemical structure of the target compound.

Example 4 External Standard Method in High Performance Liquid Chromatography to Detect the Content of Optical Isomers in Aliskiren and Its Salts

Liquid chromatograph model: Shimadzu LC-10ATvp

Chromatographic column type: CHIRALPAK AD-H chiral column (4.6mm×250mm, 5μm);

Mobile phase: n-hexane-absolute ethanol (containing 0.2% diethylamine) (90:10);

Detection wavelength: 280nm;

Flow rate: 1.0ml/min;

Column temperature: 30°C;

Injection volume: 10μl

Diluent: n-hexane: absolute ethanol (1:1)

Preparation of the reference solution: take an appropriate amount of compound 4R and 5R-1 obtained in Example 3, accurately weigh them, add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark, and obtain compounds containing 4R and 5R per ml. - 10.5 mg of solution.

Preparation of the test solution: Take an appropriate amount of Aliskiren hemifumarate (prepared and provided by China Resources Double Crane Pharmaceutical Co., Ltd. according to the method described in Example G1 in patent US7,009,078), and accurately weigh , add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark to obtain a solution containing 0.2 mg of aliskiren hemifumarate per ml.

Preparation of mixed solution with compound 4R, 5R-1: Accurately weigh aliskiren hemifumarate and appropriate amount of compound 4R, 5R-1 respectively, add n-hexane: absolute ethanol (1:1) to dissolve and make to volume to scale.

Operation: Precisely draw 10 μl of the reference substance solution, the test solution and the mixed solution of compound 4R, 5R-1 into the liquid chromatograph, and record the chromatograms (Fig. 6, Fig. 7, Fig. 8). The retention times of compounds 4R, 5R-1 and aliskiren in the above chromatograms are about 25.1 min and 21.1 min respectively, and the resolution of the two is about 2.7.

The external standard method is used to calculate the content of compound 4R and 5R-1 in the test solution: if the corresponding chromatographic peak appears in the position of compound 4R and 5R-1 in the test solution, the external standard is used according to the corresponding peak area of the reference solution. The method calculates the content of compound 4R, 5R-1 in the test solution.

Calculation formula:

Aliskiren hemifumarate compound

In the formula, _sample A is the peak area of compound 4R in the test solution, 5R-1;

W is _the sample amount (mg) that is compound 4R, 5R-1;

V _sample is the constant volume (ml) of the test solution;

A _pair is the peak area of compound 4R, 5R-1;

V is _the constant volume (ml) of compound 4R, 5R-1;

W _sample is the weighing amount (mg) of need testing solution.

The specific data are as follows:

project value 5.39mg 10.73mg 282825 31641 10ml 50ml

Compound 4R, 5R-1 content% in the test solution not detected Compound 4R, 5R-1 content% in the mixed solution 28.1%

Example 5 High Performance Liquid Chromatography Adding Calibration Factor Self-control Method to Detect the Content of Optical Isomers in Aliskiren and Its Salts

Liquid chromatograph model: Shimadzu LC-10ATvp

Chromatographic column type: CHIRALPAK AD-H chiral column (4.6mm×250mm, 5μm);

Mobile phase: n-hexane-absolute ethanol (containing 0.2% diethylamine) (90:10);

Detection wavelength: 280nm;

Flow rate: 1.0ml/min;

Column temperature: 30°C;

Injection volume: 10μl

Diluent: n-hexane: absolute ethanol (1:1)

Preparation of compound 4R, 5R-1 series linear solutions: take an appropriate amount of compound 4R and 5R-1 obtained in Example 3, weigh them accurately, add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark, and each ml contains linear stock solution of compound 4R, 5R-10.5 mg. A series of linear solutions with concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 mg/ml were obtained by serial dilution.

Preparation of aliskiren hemifumarate series linear solution: Aliskiren hemifumarate (prepared by China Resources Double Crane Pharmaceutical Co., Ltd. according to the method described in Example G1 in patent US7,009,078 and obtained) Provided) an appropriate amount, accurately weighed, added n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark to obtain a linear stock solution containing 0.5 mg of aliskiren hemifumarate per ml. A series of linear solutions with concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 mg/ml were obtained by serial dilution.

Preparation of the test solution: Take an appropriate amount of aliskiren semi-fumarate, accurately weigh it, add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark, and obtain aliskiren semi-fumarate per ml. A solution of maleate 0.2 mg.

Preparation of the control solution: Accurately measure 5ml of the test solution, place it in a 10ml measuring bottle, add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark.

Add the mixed solution of compound 4R, 5R-1: Accurately weigh the appropriate amount of aliskiren hemifumarate and compound 4R, 5R-1 respectively, add n-hexane: absolute ethanol (1:1) to dissolve and set the volume to the mark .

Chromatographic operation: Precisely draw 10 μl of each linear solution into the liquid chromatograph, and record the chromatogram. The concentration of a series of linear solutions is taken as the abscissa, and the peak area is taken as the ordinate to draw a standard curve to obtain the slope value K corresponding to the compound 4R, 5R-1, aliskiren and its salt.

Correction factors for compounds 4R, 5R-1 relative to aliskiren hemifumarate

f=K _Aliskiren /K _{4R, 5R-1}

The correction factor f value of compound 4R, 5R-1 relative to aliskiren and its salts was calculated to be 1.0055.

Precisely draw 10 μl of the test solution and the control solution respectively and inject them into the liquid chromatograph, and record the chromatograms. If a chromatographic peak appears at the position of the corresponding compound 4R, 5R-1, then its content is:

Aliskiren hemifumarate compound

In formula, A _4R5R-1 is the peak area of compound 4R, 5R-1 in need testing solution;

f _4R5R-1 is the correction factor (1.0055) of compound 4R, 5R-1 relative to Aliskiren hemifumarate;

A _pair is the peak area of Aliskiren hemifumarate in the control solution.

The specific data are as follows:

project value 31641 56695 Compound 4R, 5R-1 content% in the test solution not detected Compound 4R, 5R-1 content % 28.0%

Although specific embodiments of the present invention have been described in detail, those skilled in the art will understand. Based on all the teachings that have been disclosed, various modifications and substitutions can be made to those details, and these changes are all within the scope of the invention. The full scope of the invention is given by the appended claims and any equivalents thereof.

Claims (9)

1. the preparation method of the diastereoisomer of (2S, 4R, 5R, 7S) configuration of Aliskiren, it may further comprise the steps: a) Using the following compound (3S,5R,1'S,3'S)-4 as the starting material for synthesis, its chemical name is: (3S,5R)-5-[(1'S,3'S)-1-bromo- 3-[[4-methoxy-3-(3-methoxypropoxy)phenyl]methyl]-4-methylpentyl]dihydro-3-isopropyl-2(3H)- Furanone; b) React compound (3S, 5R, 1'S, 3'S)-4 with sodium azide to obtain compound (3S, 5R, 1'R, 3'S)-5 as shown below; the specific reaction conditions are: compound (3S, The mixture of 5R,1'S,3'S)-4 10.0g, sodium azide 6.5g, tripropylene glycol 80ml and water 53ml was stirred and reacted at 80°C for 48 hours, the reaction mixture was cooled to room temperature, and 8ml of diethylamino-1-propylamine was added , then stirred and reacted at room temperature for 3 hours; the reaction mixture was poured into 200ml of water, extracted with 3×200ml of methyl tert-butyl ether, and the organic phase was successively used with 0.5N hydrochloric acid 200ml, 5% sodium bicarbonate 200ml, water 3 ×200ml, washed with 200ml of brine, dried the organic phase with 200g of anhydrous sodium sulfate, filtered and concentrated under reduced pressure, purified by silica gel column chromatography, wherein the mobile phase was ethyl acetate/n-hexane=1:5, and 6.9g of light yellow was obtained Oil, yield 75.0%; c) react compound (3S, 5R, 1'R, 3'S)-5 with 3-amino-2,2-dimethylpropylamine to obtain compound 4R, 5R-2 as shown below; d) Compounds 4R, 5R-2 are catalytically hydrogenated to obtain compounds 4R, 5R-1; Among them, the molecular structure of the (2S, 4R, 5R, 7S) configuration diastereoisomer of Aliskiren is shown in the formula 4R, 5R-1, and the chemical name is: (2S, 4R, 5R, 7S) -5-Amino-N-(2-carbamoyl-2-methylpropyl)-4-hydroxy-2-isopropyl-7-(4-methoxy-3-(3-methoxypropyl) Oxy)benzyl)-8-methylnonanamide, 2. The preparation method of claim 1, wherein in step d), compound 4R, 5R-2 is prepared by catalytic hydrogenation of palladium carbon to compound 4R, 5R-1. 3. The preparation method according to claim 1 or 2, characterized in that one or more of the following items (1) to (8): (1) In step c), the reaction solvent is selected from methyl tert-butyl ether, tetrahydrofuran, N-methylpyrrolidone and chloroform; (2) In step c), an organic base is added to the reaction mixture, wherein the organic base is selected from pyridine, 2-hydroxypyridine, triethylamine and amantadine; (3) In step c), the reaction temperature is 40-110°C; (4) In step c), after the reaction is completed, water and a solvent are added for extraction operation, wherein the solvent is selected from methyl tert-butyl ether, dichloromethane and ethyl acetate; the organic layer is concentrated after drying, The residue was purified by silica gel column chromatography to obtain compounds 4R, 5R-2; (5) In step d), the palladium carbon is palladium carbon containing 5% to 10%; (6) In step d), the solvent of compound 4R, 5R-2 is selected from methyl tert-butyl ether, ethanol, methanol, tetrahydrofuran, ethyl acetate, ethyl isopropyl ester and dichloromethane; (7) In step d), wherein the pressure of the catalytic hydrogenation reaction is 1 to 10 bar; (8) In step d), after the catalytic hydrogenation reaction was completed, saturated sodium bicarbonate solution and brine were sequentially added for extraction operation, the organic layer was dried and then concentrated, and the residue was purified by silica gel column chromatography to obtain compounds 4R, 5R-1. 4. The preparation method according to claim 3, wherein the reaction solvent in step c) is methyl tert-butyl ether. 5. The preparation method according to claim 3, wherein the organic base added in the reaction mixture in step c) is 2-hydroxypyridine. 6. The preparation method according to claim 3, wherein the reaction temperature in step c) is 60-100°C. 7. The preparation method according to claim 3, wherein the reaction temperature in step c) is 70-90°C. 8. The preparation method of claim 3, wherein the solvent of compound 4R, 5R-2 in step d) is methanol or tetrahydrofuran. 9. The preparation method according to claim 3, wherein the pressure of the catalytic hydrogenation reaction in step d) is 1-3 bar.