WO1997000851A1

WO1997000851A1 - Chemical compounds and methods of production thereof

Info

Publication number: WO1997000851A1
Application number: PCT/GB1996/001481
Authority: WO
Inventors: Peter Samuel James Cheetham; Nigel Eric Banister
Original assignee: Zylepsis Limited
Priority date: 1995-06-23
Filing date: 1996-06-21
Publication date: 1997-01-09
Also published as: JPH11507941A; AU6132796A; EP0833812A1

Abstract

A compound having formula (B) and salts or adducts thereof wherein R1 and R2 are the same or different and represent H, OH, NH2, CO2H or OR6; R4 and R5 are the same or different and represent H, OH, NH2 or OR6; R6 is a straight or branched chain C1-C16 alkyl, alkylene or alkylyne or a substituted or unsubstituted homocyclic or heterocyclic aromatic group; R3 is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring which is in conjugation with a group R7; R7 is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring, an alkene, or an alkane substituted with a functional group capable of entering into conjugation with R3. Such a compound has the ability to absorb ultraviolet radiation in both the uvA and uvB regions of the ultraviolet spectrum and antioxidant activity, making it useful as an additive in a sunscreen composition and in a variety of cosmetic and non-cosmetic compositions including hair care products, inks, paints and dyes.

Description

CHEMICAL COMPOUNDS AND METHODS OF PRODUCTION THEREOF

The present invention relates to novel compounds having properties which make them useful as sunscreen additives, processes for their preparation and formulations containing them, including formulations of cosmetic products.

As the harmful effects of strong sunlight become more widely publicized and concern grows over the depletion of the ozone layer, the general public is becoming more aware of the harmful effects of atmospheric ultra-violet radiation. In particular, the identification of atmospheric radiation as a major causative agent in skin cancers has increased the demand for effective and economic protection against atmospheric ultra- violet radiation.

Of the three types of ultraviolet radiation, uvA, uvB and uvC, uvC does not penetrate the earth's atmosphere, being absorbed by the ozone layer. Of the two types of ultraviolet radiation that reach the earth's surface, uvB has been identified as the causative agent of skin cancer. Accordingly, the majority of sunscreens currently available concentrate on the reduction of uvB rays contacting the skin. However. uvA has now been identified as a cause of ageing of skin and hair wrinkling. As such, it is considered preferable to provide sunscreen agents which reduce the harmful effects of both uvA and uvB in sunlight.

When used in cosmetic preparations there is a desire in the art to produce sunscreens which not only have the primary function of blocking ultraviolet light but also have the secondary function of caring for the skin to which they are applied. Thus many sunscreens also contain moisturisers and antioxidants as skin care additives.

Users of sunscreens require new materials with improved uv radiation absorbing properties in order to create improved products with substantially superior protective properties. These products would be advantageous for a variety of applications where uv protection is important, for example in a range of personal care products such as hair shampoos, conditioners and hairsprays, in polymers, inks, colouring materials such as paints and dyes and also to prevent uv induced degradation of other actives and additives formulated or added to a system. Ideally, such materials should exhibit the following properties:

• Intense and broad spectrum absorbance covering both the uvB and uvA regions, so that very effective protection against cancer causing uvB radiation and skin-ageing uvA radiation can be achieved using easily co-formulated materials.

• Combined uvA and uvB absoφtion in just one molecule, instead of current products that must contain mixtures of molecules with different uv absorbing properties.

• High uv absorbance, thermostability and photostability, so that higher sun protection factor (SPF) products can be made much more easily, or so that lower concentrations of uv absorbing materials can be used.

• Antioxidant activity.

It has now surprisingly been discovered that certain novel compounds show a marked increase in uvB absorption and/or a particularly good ability to absorb light emitted in the uvA and uvB wavelength regions of ultraviolet radiation.

According to the present invention there is provided a compound of the formula B

(B)

and salts or adducts thereof,

wherein

R, and R₂ are the same or different and represent H, OH, NH₂, C0₂H or OR₆

R₄ and R₅ are the same or different and represent H, OH, NH₂ or OR₆

R₆ is straight or branched chain C, - C₁₆ alkyl, alkylene or alkylyne or a substituted or unsubstituted homocyclic or heterocyclic aromatic group

R₃ is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring which is in conjugation with a group R₇

R₇ is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring, an alkene, or is an alkane substituted with a functional group capable of entering into conjugation with R₃

The preferred compounds of this invention may be used in sunscreen preparations that have the ability to absorb uv radiation in both the uvA and uvB region and measurements of this property are expressed by the terms defined below.

The definition of the values in. a. v. and E^{ι i} _knι are as follows: m.a.v. is the molar absorbance value (E) being the absorbance of one molar solution of a substance, measured in a 1cm path length cell at the given wavelength. E^1% _lcm is the specific absorbance of a substance being the absorbance of that substance at 1 % concentration in a 1 cm path length cell at the given wavelength. The total uv absorbance is a representation of the area under the curve of the specific absorbance over the range 290nm to 450nm.

The preferred compounds described herein exhibit m.a.v. values > 1 x 10⁴ at wavelength maxima and exhibit a total uv absorbance > 4 x 10⁴.

Unexpectedly, it has further been discovered that for many of the compounds of the invention, an alteration in pH of a solution of the compound results in an advantageous change in uv spectrum with a change in the measured λmax often resulting in two maxima where previously there had been one. This is embodied in the appearance of λmax in the uvA region of the spectrum in addition to a λmax in the uvB region and causes an increase in the total uv absorbance. The nature of the ionic species involved in changing the pH influences the extent of alteration of the UV spectrum. This allows for manipulation and alteration of the uv absorbance characteristics exhibited by the chemical compound. Alteration of the pH as described above can be effected by the use of acids or bases or Lewis acids or bases or solutions of buffer preparation containing these. Solutions of alkaline metal salts such as sodium hydroxide are, for example, of use in this respect. (See Advanced Organic Chemistry; Reactions. Mechanisms and Structure; J. March, McGraw-Hill, New York, 1968.)

Preferred embodiments of the present invention include compounds which individually exhibit combined uvA and uvB absoφtion properties. Accordingly, by using such a compound, rather than using separate compounds each exhibiting only one of either uvA or uvB absoφtion properties, the manufacture of product formulations is facilitated.

Preferred embodiments of the invention also include compounds which exhibit antioxidant activity. The antioxidant activity can be measured by one of two primary methods. One method is based on the protection of lipids from oxidation and is described in Fat Sci. Technol., 1992, 94, 428 by Marinova and Yanishlieva. Another method is based on the measurement of antiradical activity as described in Lebensm. -Wiss. u-Technol , 1995, 28, 25 by Brand-Williams, Cuvelier and Berset. Suitable examples of R₃ include the following or salts thereof:

wherein the alkene bond can be either cis or trans,

or

wherein the alkene bond can be either cis or trans and where C0₂X can represent an acid or ester moiety.

or

which can be present in the form depicted or in the monocyclic form which arises from hydrolytic cleavage of the cyclic ketone i.e.,

wherein the alkene bond can be either cis or trans,

or

wherein the alkene bond can be either cis or trans and where C0₂X can represent an acid or ester moiety,

or

Preferably, the group C0₂X mentioned above as an example of R₃ represents an ester moiety. Particularly preferred esters include 2- (ethyl)hexyl esters or 2-ethoxyethyl esters, ie. C,H,

I

X = -CH₂CHC₄H₉, or -CH₂CH,OCH,CH₃

Conveniently, X represents a straight or branched chain C, - C₁₆ alkyl, alkene, or alkylyne optionally incoφorating a hetero atom replacement of a carbon to give, for example, an ether; also substituted or unsubstituted ring compounds, either homocyclic or hetercyclic including aromatic ring compounds.

Substitution of the above preferred examples of R₃ is optional.

A skilled person will appreciate that in some cases R₃ will contain functional groups capable of forming salts or polarised associations with other ionic entities such as added acids or bases.

The present invention enables a large number of different formulations to be produced so as to cater precisely for particular consumer and product requirements. In addition, in certain preferred embodiments, which comprise isomers which may be present in two forms, such as a trans form and a cis form, photochemical energy may be dissipated by reversible trans-cis isomerisation. This is a mechanism that is indicative of good photochemical stability.

The common structural feature of the compounds of the present invention including each of the following examples:-

is that the ester radical R₃ is an aromatic ring further conjugated with a multiple bond or functional group capable of entering into conjugation. The conjugation may be continued through the carbon-carbon double bond to a carbonyl function in the form of a cyclic ester as in Structure I or in the form of an acid as in Structure II above. The carbonyl function may also be in the form of an ester of an acid e.g. the methyl ester of Structure II above.

The addition of base, which creates a corresponding salt or adduct, causes a shift in uv spectrum, resulting in compounds with improved properties. It is likely that, for the cyclic esters, the shift in uv spectrum may be accompanied by a ring opening reaction, for example as shown below:-

or

Umbelliferyl 4-methoxycinnamate (Structure III) is a novel molecule that provides very intense absorption, double that of octyl methoxycinnamate, with a λmax. of 321 nms. Upon addition of NaOH, intense and combined uvA and uvB absoφtion is obtained with λmax. of 376 and 310nms respectively. Such absorption is superior to that exhibited by known mixtures of uvA and uvB absorbing materials.

Preferably, R, represents hydroxy. The presence of a 4-hydroxy group appears to allow the UV absoφtion effect of the molecule to be shifted more into the uvA region by adjusting the pH of a formulation containing the molecule.

Particularly preferred compounds of the invention include esters of ferulic acid, ie. compound B wherein R, = OH, R₂ = OCH₃. and R₄ and R₅ = H. Ferulic acid and its ester derivatives exhibit advantageous antioxidant activity.

Ferulic acid esters of especial interest include

A skilled person will be able to synthesise the above preferred ferulic acid esters using standard methods. For example, compound (a) can be made by protecting the 4-hydroxy functionality of ferulic acid with a chemical protecting group which can be later removed such as an acetyl or benzyl group as described, for example, in Vogel's Textbook of Practical Organic Chemistry, A Vogel, revised B Furniss et al, Longman Scientific & Technical Publishing, 1989. Then formation of an acid chloride and reaction with ferulic acid (R = OCH₃) would form a cinnamate ester. Formation of a second acid chloride and reaction with 2-ethylhexan-l-ol is then followed by removal of the protecting group to give compound (a). An alternative approach is to use an enzyme catalysed reaction to condense 4-hydroxycinamate acid (R = H) with ferulic acid and then again use enzyme catalysis to add the 2-ethylhexyl ester radical.

The 2-ethoxyethyl esters can be prepared in the same ways using 2-ethoxyethanol in place of 2-ethylhexan- l -ol .

A further preferred compound of the invention is

Methods for the preparation of the compounds embodied herein include methods for the formation of esters. Enzyme catalysed reaction to form an ester may be as described in outline in Enzymes in Synthetic Organic Chemistry. C-H Wong and G M Whitesides. Pergamon, Elsevier Science Ltd, 1994. Methods for coupling the acid functionality of a substituted cinnamic acid, for example caffeic acid, with an alcohol group, for example hydroxycinnamic acid, to form an ester encompassed by structure B are suitable. For the various products disclosed these methods can include dehydration by azeotropic water removal, as described for example in Vogel's Textbook of Practical Organic Chemistry, A Vogel, revised B Furniss et al, Longman Scientific & Technical Publishing, 1989; mechanical or chemical water removal; conversion of the acid functionality to an activated derivative e.g. acid halide or activated ester followed by reaction with the alcohol; transesterification of a suitable ester derivative; enzyme catalysed ester formation from the acid and alcohol structure; enzyme catalysed transesterification of a suitable structure, e.g. chlorogenic acid. It will be apparent to a skilled person that control of the relative quantities of substrate and reagents used in the protocol for ester formation will determine the extent of ester formation.

In order to illustrate the features and advantages of the present invention, preferred embodiments of the present invention will be further described with reference to the following examples:-

EXAMPLE 1

3,4-Dimethoxycinnamyl chloride synthesis.

3,4-dimethoxycinnamic acid (52Jg, 0.25 mole) and thionyl chloride (28ml, 0.38 mole) were boiled under reflux in dry toluene (400ml) for 1 hour. The excess thionyl chloride was removed by repeated evaporation under vacuum from toluene. The solution was evaporated under vacuum to dryness to leave dimethoxycinnamyl chloride as a brown solid which was used without further purification. EXAMPLE 2

4-Methoxycinnamyl chloride synthesis.

The procedure used here was identical to that described in example 1 with the use of 4-methoxycinnamic acid. The resulting product obtained was used without further purification.

EXAMPLE 3

Umbelliferyl 3.4-dimethoxycinnamate (3.4-Dimethoxycinnamic acid ester with 7-Hydroxycoumarin) synthesis.

The unpurified dimethoxycinnamyl chloride prepared in example 1 (25 mmole) was resuspended in toluene and added to umbelliferone (7-hydroxycoumarin. 3.9g, 25 mmole). The mixture was boiled under reflux for 1 hour and then left to cool. The resulting precipitate was filtered, dried and then recrystallised from ethanol to yield a white solid, m.p. 181-183°C.

The UV spectrum of this material when measured as 0.001 % w/v solution in ethanol exhibited a λmax of 335nm; m.a.v. of 26787; E^1%, of 761. The addition of sodium hydroxide solution to the ethanolic solution gave a resulting UV spectrum of; λ_max of 328nm; m.a.v. of 19782; E^1% _lcm of 562 and also λ_max of 375nm; m.a.v. of 16614; E^I% _lcm of 472.

Η nmr, δ, J in Hz, (270 MHz, DMSO-d₆): 8.10 [IH, d. J 9.6]; 7.84 [IH, d, J 15.9]; 7.81 [IH, d, J 8.3]; 7.48 [IH, d, J 1.9]; 7.38 [IH, d, J 2.2]; 7.36 [IH, dd, J 8.2, 1.9]; 7.24 [IH, dd, J 8.2, 2.2]; 7.03 [IH, d, J 8.2]; 6.84 [I H, d. J 15.9]; 6.49 [IH, d, J 9.6] ; 3.84 [3H, s]; 3.82 [3H,s] .

EXAMPLE 4

4-Cinnamyl 3,4-dimethoxycinnamate (3.4-Dimethoxycinnamic acid ester with 4-hydroxycinnamic acid) synthesis.

The unpurified dimethoxycinnamyl chloride prepared in example 1 ( 0.25 mole) was resuspended in toluene (400ml) and -coumaric acid

(4-hydroxycinnamic acid, 41. Og, 0.25 mole) was added. The mixture was boiled under reflux for 1 hour and then left to cool. The resulting beige solid was recrystallised twice from DMF/EtOAc to yield a light beige solid (36.6g, 41 %) which was 85 % pure and contained 15 % of a double ester i.e. 4-(4-cinnamyl)cinnamyl 3,4-dimethoxycinnamic acid. At 90: 10 ratio of products the m.p. was 194-197 ^° C

The UV spectrum of this material when measured as a 0.001 % solution in ethanol exhibited a λ_lluv of 300nm; m.a.v. of 24743; E^1% _lcm of 697 and λ_max of 328nm; m.a.v. of 25773 : E^l* _κ._nι of 726.

'H nmr. δ, J in Hz, (270 MHz, DMSO-d₆): 12.44 [IH, br s,]; 7.82 [IH, d. J 15.8]; 7.78 [2H, d. J 8.8] : 7.63 [I H, d. J 16.0]; 7.46 [IH, d, J 1.6]; 7.35 [IH, dd, J 8.5, 1.6]: 7.26 [2H, d,J 8.5] ; 7.03 [I H, d. J 8.6]; 6.82 [IH, d, J 15.8]; 6.54 [ I H, d. J 16.0]; 3.83 [3H, s]; 3.82 [3H, s] .

EXAMPLE 5

Umbelliferyl 4-methoxycinnamate (4-Methoxycinnamic acid ester with 7-hydroxycoumarin) synthesis.

The unpurified 4-methoxycinnamyl chloride (0.57 mole) as prepared in example 2 was resuspended in toluene (500ml) and added to umbelliferone (92Jg, 0.57 mole). The mixture was boiled under reflux for 1 hour and the precipitate which formed upon cooling was filtered, dried and recrystallised from DMF/EtOAc to yield a white solid (158.6g, 86%). m.p. 194-196 ° C.

The UV spectrum of this material when measured as a 0.001 % solution in acetonitrile exhibited a λ„ _ιϊ of 321 nm: m.a.v. of 43253 : E 1 %

1cm of 1342.

The addition of sodium hydroxide solution to the solution gave a resulting UV spectrum of, λ_max of 310nm; m.a.v. of 23721 ; E^{1 %} _lcm of 736 and also λ_max of 376nm; m.a.v. of 17984; E^{1 %} _lcm of 538.

Η nmr, δ, J in Hz, (270 MHz, DMSO-d₆): 8.10 [IH, d, J 9.5]; 7.87 [IH, d, J 16.1]; 7.81 [I H, d, J 8.2]; 7.80 [2H, d, J 8.9]; 7.38 [I H, d, J 2.2]; 7.24 [IH, dd,J 2.2. 8.5]; 7.03 [2H, d, J 8.9]; 6.76 [I H, d, J 16.1]; 6.50 [ IH, d, J 9.5]; 3.83 [3H, s] .

EXAMPLE 6

4-Cinnamyl 4-methoxycinnamate (4-Methoxycinnamic acid ester with 4-Hvdroxycinnamic acid) synthesis.

The unpurified 4-methoxycinnamyl chloride (28 mmole) as prepared in example 2 was resuspended in toluene (40ml) and added to -coumaric acid (4.6g, 28 mmole). The mixture was boiled under reflux for 1 hour and the mauve precipitate which formed upon cooling was filtered and washed with diethyl ether to yield a white solid. This was dried with heating in vacuo to yield the title compound. (8.08g, 75 % purity, 97% yield). The main impurity was the diester as described in example 8.

The UV spectrum of this material when measured as a 0.001 % solution in ethanol exhibited a λ_ιnax of 312nm: E^{, s} „_ιn of 908.

Η nmr, δ, J in Hz, (270 MHz, DMSO-d₆): 7.84 [I H, d, J 15.9]; 7.78 [4H, d, J 8.8]; 7.63 [IH, d, J 15.9]; 7.26 [2H, d, J 8.8]; 7.02 [2H, d, J

8.8]; 6.73 [IH, d, J 15.9] ; 6.53 [ I H, d. J 15.9] ; 3.82 [3H, s].

EXAMPLE 7

Isoeugenyl 3.4-dimethoxycinnamate. (3.4-Dimethoxycinnamic acid ester with isoeugenol) synthesis.

3,4 Dimethoxycinnamic acid (5g) was added to freshly distilled thionyl chloride (70ml) and dry benzene (50ml), and the mixture was boiled under reflux for 1 hour. The excess thionyl chloride was removed by repeated rotary evaporation with benzene being added each time to ensure complete removal. The crude acid chloride was then resuspended in benzene and added to isoeugenol (50ml), and the mixture was boiled under reflux for 40 mins. The cooled mixture was added to IM NaHC0₃ solution (100ml) with careful release of pressure. The organic phase was removed and washed again with I M NaHC0 solution (4 x 100ml), dried over Na₂S0₄ (anhydrous) and rotary evaporated to dryness. The crude ester was recrystallised from ethanol to give a fine tan powder in 58 % yield, with a purity, determined by nuclear magnetic resonance (nmr), of approximately 90% , melting point (m.p.) 130-132°C.

The UV spectrum of this material when measured as a 0.001 % solution in ethanol exhibited a λ_max of 300nm; E^{1 <;!} _lcm of 571 and also λ_max of 327.5nm: E' ._m of 689.

^]H nmr, δ, J in Hz, (270 MHz. CDCl,): 7.81 [IH, d, J 15.9]; 7.15 [IH, dd, J 1 .9, 8.1]; 7.1 1 [IH, d. J 1.9]; 7.02 [IH, d, J 8.1]; 6.96-6.86 [3H, m] ; 6.54 [I H, d, J 15.9] ; 6.38 [ I H, dd. J 15.6, 1.4]; 6.19 [I H, dd. J 15.6, 6.6]; 3.92 [3H, s] ; 3.91 [3H, s] ; 3.84 [3H ,s] ; 1.88 [3H, dd, J 6.3, 1.4] .. EXAMPLE 8

4-(4-Cinnamyl)cinnamyl 4-methoxycinnamate (4-Cinnamyl

4-methoxycinnamic acid ester with 4-hydroxycinnamic acid) synthesis.

To 4-methoxycinnamic acid (l .Og, 5.6 mmole) in benzene (10ml) was added thionyl chloride (14ml, 0J9mole) to form the acid chloride as described in example 2. To this was added 4-hydroxycinnamic acid 0.9g, 5.6 mmole) and the reaction mixture boiled under reflux for 1 hour. The precipitate which formed upon cooling the mixture (1 .6g) was recrystallised from ethanol to give the title compound (1 .4g).

The UV spectrum of this material when measured as a 0.001 % solution in ethanol exhibited a λ_m.._ of 314nm; m.a.v. of > 36989; EX .,,, of > 787.

Η nmr, δ. j in Hz, (270 MHz, DMSO-d₆): 7.92 [I H. d. j 16.2] : 7.91 [2H, d, J 8.6]; 7.85 [I H, d, j 15.9] ; 7.80 [2H, d, j 8.8]; 7.78 [2H. d, J 8.8]; 7.66 [IH, d, j 15.4]; 7.31 [2H. d, J 8.6]; 7.28 [2H, d, j 8.8]; 7.02 [2H, d, J 8.8]; 6.90 [I H, d, 15.9]; 6.75 [ l H,d, 15.9] ; 6.54 [I H. d, J 16.0]; 3.82 [3H, s].

As can be seen from Examples 3 and 5 above, addition of a base such as a Lewis base to certain preferred compounds of the present invention causes a shift in the ultraviolet spectrum for the compound, often with the appearance of a wavelength maxima in the uvA region of the spectrum in addition to a wavelength maxima in the uvB region of the spectrum and an increase in total ultraviolet absorbance.

The compounds of the present invention. including the preferred compounds described in Examples 1 to 8, may be incoφorated into product formulations such as creams, lotions and emollients either directly as produced above or, alternatively, in the form of a salt or adduct thereof, for example, following addition of a base. Creams, lotions and emollients produced in this way are particularly useful as sun-care products due to their sunscreening effects which may be in both the uvA and uvB regions. Furthermore, such formulations are also useful as health-care and/or cosmetic products because many of the compounds of the present invention have other useful properties such as antioxidant and antimicrobial activities and can help prevent or mitigate wrinkling and/or ageing of the skin and hair.

The creams, lotions or emollients into which the compounds of the present invention may be incorporated may be water-based or oil-based many may contain other useful components providing such properties as aroma, skin permeability, moisturisers, antioxidants and antimicrobial components.

Compounds of the present invention also have uses outside the cosmetic industry. The thermostability and solubility characteristics of these novel compounds together with their uv absorbing properties make them suitable for a variety of applications including incoφoration into fabrics, dyes, polymers, inks, paints and other chemical compositions to confer protection from light induced decomposition. EXAMPLE 9

Sunscreen

A sunscreen oil formulation comprises a compound of the invention and an adjuvant as follows:

cyclomethicone 64.9 % weight

UV absorber 6.0% weight capric/caprylic triglyceride 5.0% weight fragrance 0J % weight isopropyl palmitate 24.0% weight

The UV absorber is a compound of the invention. The relative proportion of active UV absorber can be varied to alter the level of protection afforded by the sunscreen oil.

A water in oil sunscreen lotion of the invention comprises:

UV absorber 7.5 % weight isopropyl palmitate 6.0% weight stearic acid 3.0 % weight cetyl alcohol 1 .0% weight glycerol monostearate 1.0% weight water 66.5 % weight sorbitol 3.0% weight Carbomer 934 (2 % dispersion) 10.0% weight triethanolamine 1 .2% weight fragrance and preservative 0.8 % weight

Again, the relative proportion of active UV absorber can be varied to alter the level of protection afforded by the sunscren lotion. EXAMPLE 10

Hair products

Incoφoration of the compounds of the invention into hair products such as shampoos, conditioners, mousse and colorants is a preferred application. In the following examples the percentages refer to the weight of he ingredients.

(a) Conditioner formulation

Distearyl dimethyl ammonium chloride 2.40%

Hydroxyethyl cellulose 1.00%

Cetyl alcohol 2.00% Emulsifying wax 0.50%

Perfume 0.50%

UV absorber 2.00%

Water to 100.00%

(b) Hair spray formulation

Vinyl acetate/crotonic acid copolymer 1.60%

Aminomethyl propanol 0.15 % PEG-75 Lanolin 0.20%

Ethanol 67.05 %

Butane 30.00%

UV absorber 1.00%

(c) Hair mousse formulation

Polyquaternium- 1 1 3.00%

Polyquaternium-4 1.50%

Hydrogenated tallow trimonium chloride 0.20%

Nonoxynol-10 0.35 %

Ethanol 10.00%

Water 73.45 %

Butane-48 10.00%

UV asborber 1.50% In each case the relative amounts of ingredients can be varied to alter the properties of the product as desired.

EXAMPLE 11

Use of UV absorbers in plastics:

The UV absorber compound is incoφorated at 0.5 % w/w into polyolefin material prior to extrusion to form a plastic film which exhibits resistance to light-induced decomposition.

Claims

A compound having the formula:

and salts or adducts thereof, wherein

R, and R₂ are the same or different and represent H, OH, NH₂, C0₂H or OR₆,

R₄ and R₅ are the same or different and represent H, OH, NH₂ or OR₆,

R₆ is a straight or branched chain C , - C₁₆ alkyl, alkylene or alkylyne or a substituted or unsubstituted homocyclic or heterocyclic aromatic group,

R₃ is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring which is in conjugation with a group R₇,

R₇ is a substituted or unsubstituted homocyclic or heterocyclic aromatic ring, an alkene, or an alkane substituted with a functional group capable of entering into conjugation with R₃.

2. A compound according to Claim 1 which exhibits a molar absorbance value (m.a.v.) measured in a 1 cm path length cell, of more than 1 x IO⁴ at the wavelength of maximum absorbance, and/or exhibits a total ultra-violet absorbancy of at least 4 x 10⁴ Abs nm for a 1 % weight/volume solution.

A compound according to Claim 1 or 2, where R₃ comprises:

CH₃

and wherein the alkene bond is either cis or trans.

4. A compound according to Claim 1 or 2 wherein R₃ is

and wherein the alkene bond is either cis or trans and C0₂ X represents either an acid or ester moiety.

5. A compound according to Claim 1 or 2 wherein R₃ comprises:

6. A compound according to Claim 1 or 2 wherein R₃ comprises:

and wherein the alkene bond is either cis or trans.

7. A compound according to Claim 1 or 2 wherein R₃ comprises:

and wherein the alkene bond is either cis or trans and C0₂X represents an acid or ester moiety.

8. A compound according to Claim 1 or 2 wherein R₃ comprises:

9. A compound according to any of Claims 1 to 8 wherein R, is a para methoxy group.

10. A compound as claimed in any one of Claims 1 to 8 wherein R, represents OH and R₂ represents -OCH₃.

11. A compound as claimed in Claim 4 or 7, wherein C0₂X represents an ester moiety in which X is a straight or branched chain Cj - C₁₆ alkyl, alkene, alkylene which optionally incoφorates a hetero atom replacement of a carbon; or a substituted or unsubstituted homocyclic or heterocyclic ring.

12. A compound as claimed in Claim 4 or 7 wherein C0₂X represents an ester moiety in which

X = -CH₂CHC₄H₉, or -CH₂CH₂0CH₂CH₃

13. A compound comprising a compound according to any of Claims

1 to 12, which compound has been subjected to an alteration in pH conditions which causes a shift in the ultra-violet absorbtion spectrum of the original compound.

14. A compound according to Claim 13, wherein the alteration in the pH conditions results in an increase in total ultra-violet absoφtion.

15. A compound according to Claim 13 or 14, wherein the alteration in pH conditions results in the appearance of an additional wavelength maxima.

16. A compound according to Claim 15, wherein the additional wavelength maxima is in the uvA region of the ultra-violet spectrum.

17. A compound according to any one of Claims 13 to 16, wherein the alteration in the pH conditions is brought about by addition of a base.

18. A compound according to any of Claims 1 to 17, comprising a caffeate derivative.

19. A compound according to any of Claims 1 to 17, comprising an coumarate derivative.

20. A compound having the formula:

and salts or adducts thereof, wherein

R, and R₂ are the same or different and represent H, OH, NH₂, C0₂H or OR*,

R₄ and R₅ are the same or different and represent H, OH, NH₂ or 0R₆,

R₆ is a straight or branched chain C, - C,₆ alkyl, alkylene or alkylyne or a substituted or unsubstituted homocyclic or heterocyclic aromatic group,

R₃ is an aromatic ring to which is conjugated a group R₇, R₇ is either a homocyclic or heterocyclic aromatic ring or an unsaturated aliphatic group.

21. A method of producing a compound of any of Claims 1 to 20, which comprises esterification of 3, 4-dimethyoxycinnamyl chloride.

22. A method of producing a compound according to any one of Claims 1 to 20, which comprises esterification of 4-methoxycinnamyl chloride.

23. A compound according to any of Claims 1 to 20, for use in the prevention or reduction of ultra-violet light damage to the skin or hair of warm-blooded animals.

24. Use of a compound according to any of Claims 1 to 20, for the manufacture of a medicament for the prevention of or reduction of ultra¬ violet light damage to the skin of warm-blooded animals.

25. A cosmetic method of skin preservation, which method comprises applying to the skin a composition comprising a compound according to any of Claims 1 to 20. 26. A cosmetic method of preventing or reducing wrinkling of skin or hair, which method comprises applying to the skin or hair a composition comprising a compound according to any one of Claims 1 to 20.

27. A sunscreen composition comprising a compound according to any of Claims 1 to 20 and an adjuvant.

28. A cosmetic composition comprising a compound according to any of Claims 1 to 20 and an adjuvant.

29. An anti-wrinkling composition for application to the skin or hair which composition comprises a compound according to any of Claims 1 to 20 and an adjuvant.

30. A composition for application to the skin or hair, which composition comprises a compound according to any one of Claims 1 to 20 and an adjuvant.

31. Use of a compound as claimed in any one of Claims 1 to 20 as an additive in a composition selected from hair care products, polymers, and colouring materials such as inks, paints and dyes.

32. A method of shifting the ultraviolet absoφtion spectrum of a compound as claimed in any one of Claims 1 to 12, or 18 to 20 comprising altering the pH conditions of the compounds environment.

33. A method as claimed in Claim 32 wherein the alteration in pH conditions is effected by addition of a base.