CA1294882C - Pyrimidine derivative based compositions to promote and stimulate hair growth and to counteract hair loss - Google Patents

Abstract

The invention relates to a composition for inducing and stimulating hair growth and reducing hair loss, based on pyrimidine derivatives. The composition according to the invention is characterized in that it comprises, in an essentially aqueous and thickened medium, at least one compound corresponding to the general formula: - (I) <IMG> in which R1 denotes a group <IMG> in which R3 and R4 are identical or different, represent a hydrogen atom or an alkyl, alkenyl, alkylaryl or lower cycloalkyl group, or else R3 and R4 form with the nitrogen atom to which they are linked a heterocycle chosen from aziridinyl groups , azetidinyl, pyrrolidinyl, piperidinyl, hexahydroazepinyl, heptamethyleneimine, octamethyleneimine, morpholine and lower alkyl-4-piperazidinyl, the heterocyclic groups being able to be substituted on the carbon atoms by one to three lower alkyl, hydroxy or alkoxy groups; R2 denotes a hydrogen atom or an alkyl, alkenyl, alkylalkoxy, cycloalkyl, aryl, alkylaryl, arylalkyl, alkylarylalkyl, alkoxyarylalkyl or lower haloarylalkyl group, or one of its cosmetically or pharmaceutically acceptable acid addition salts, in a concentration at least equal to the solubility limit of the compound of formula (I) in the medium. This composition has the advantage of not being irritating and oily and of not sticking to the hair.

Description

The invention relates to new compounds to induce and stimulate hair growth and decrease their fall, based on pyrimidine derivatives.
Man has a capital of 100,000 to 150,000 hairs and it is normal to lose 50 to 100 hairs daily.
The maintenance of this capital essentially results from the fact that the life of a hair is subject to a cycle called cycle hair during which the hair is formed, grows and falls before being replaced by a new item that appears in the same follicle.
We observe during a successive hair cycle There are three phases: namely, the anagen phase, the phase catagen and the telogen phase.
During the first phase, called anagen, the hair goes through a period of active growth associated with intense metabolic activity in the bulb.
The second phase called catagen is transient and it is marked by a slowdown in mito-ticks. During this phase, the hair undergoes an evolution tion, the follicle axophies and its dermal implantation appears higher and higher.
The so-called telogen terminal phase corresponds to a rest period of the follicle and the hair ends up falling out grows by an incipient anagen hair.
This process of permanent physical renewal undergoes a natural evolution during aging, the hair becomes thinner and its cycles more short.
Alopecia occurs when this process of physical renewal is accelerated or disrupted, that is say that the growth phases are completed, the ~ b 3 ~ 2 hair transition to the telogen phase is earlier and more hair is falling out. The cycles of successive growths lead to more and more hair thinner and shorter and shorter, slowly changing little down. This phenomenon can lead to baldness.
The hair cycle is dependent on many factors that can cause more or less pronounced alopecia. Among these factors r we can cite the ~ food actors, endocri-niens, nervous, .... The variations of the different categories hair streaks can be determined by tricho-gram.
We have been researching for many years in the cosmetic or pharmaceutical industry of compositions to suppress or reduce ef ~ and alopecia and in particular to induce or stimulate the growth of hair.
With this in mind, compounds have already been proposed such as amino-6 dihydro-1,2 hydroxy-1 imino-2 piperi-4-dino pyrimidine and its derivatives. Such compounds are described in particular in US Patent No. 4,139,619.
We also proposed in the patent application international WO-A-83 02 558 to associate retinoids with aforementioned compounds.
Preparations based on amino-6 dihydro-1,2 hydroxy-l 2-imino-4 piperidino-pyrimidine generally contain-also water, ethyl alcohol and propylene glycol or mixtures of these compounds taken two by two From such compositions, however, have the disadvantage of sticking charging the hair, making it greasy and sticky.
This disadvantage becomes more pronounced after applications , repeated topicals. Such compositions although having a efficacy on hair growth, 'do not prove not completely satisfactory on the cosmetic level.
In addition, the solvents used to present the active substance in solution are present in high proportions and they can be irritating.
The Applicant has discovered that it is possible to improve the effectiveness of pyrimidines having an effect on hair growth using these compounds in concentrations at least equal to their solubllite limit in thickened aqueous media.
She noted that this composition had a activity at the level of induction and stimulation of hair growth and action on decreasing the fall.
She noted in particular that the effectiveness was greater than or at least equal to that of the compositions previous for lower doses of active substance and for lower application frequencies.
The composition according to the invention leads to improved skin bioavailability of the substance active.
Furthermore, these compositions are particular.
stable in storage. Finally, use in the form thickened also allows good storage at the level of the horny layer.
The essentially aqueous compositions present also try, compared to the compositions of art the advantage of not being irritating and oily and not to stick the hair.
The present invention therefore relates to a composition in thickened, stable form, based on derivatives pyrimidine.
The composition to induce and stimulate growth ~
hair growth and decrease hair loss, based on the pyrimidine, according to the present invention, is essential characteristically characterized by the fact that it comprises in a essentially aqueous and thickened medium, at least one compound corresponding to the general formula:
OH
H2 ~ ~ NH (I)

2 ~
R
in which Rl designates a group -N

in which R3 and R4, identical or different, represent a hydrogen atom or an alkyl group, preferably having 1 to 4 carbon atoms, alkenyl, alkylaryl or lower cycloalkyl, or else R3 and R ~ form with the atom ; nitrogen to ~ uel they are linked a selected heterocycle. Between others among the aziridinyl groups, a ~ etidinyl, pyrrolidinyl, piperidinyl, hexahydroazepinyl, heptame-thyleneimine, octamethyleneimine, morpholine and alkyl lower-4-piperazidinyl, heterocyclic groups ; can be substituted on carbon atoms by one to three lower alkyl, hydroxy or alkoxy groups; R2 denotes a hydrogen atom or an alkyl group, ~ L ~ g ~
alkenyl, alkylalkoxy, cycloalkyl, aryl, alkylaryl, arylalkyl, alkylarylalkyl, alkoxyarylalkyl or haloaryl-lower alkyl, or one of its acid addition salts cosmetically acceptable, in at least one concentration equal to the solubility limit of the compound of formula (I) in the middle.
According to a preferred embodiment, the concentration of the compound of formula (I) is greater than its solubility limit so that the thickened aqueous medium comprises at least part of the compounds of formula (I) in suspension, in the form of particles. ;
The compound of formula (I) is found in particular in suspension in the form of particles having a granule: Lome-sorting average less than 80 jum, preferably less than 20 ~ um and more particularly less than 5 Jum.
The preferred implementation form is constituted by the use of compound (I) in micronized form.
The active substance used in accordance with the invention is in the form of a crystalline powder obtained in particular by dry grinding in a mortar mechanically until particles having prefe-Rence an average diameter less than 20 ~ um and preferably less than 5 µm or by air flow micronization.
We call essentially aqueous medium, uses in accordance with the invention, a medium containing less than 20%
of solvent and preferably between 1 and 10% of solvent.
The solvent is chosen from inferior alcohols laughing, alkylene glycols and alkylene alkyl ethers glycols or dialkylene glycols.
413 ~ 2 The compounds of formula (I) more particularly preferred are chosen from the compounds in which R2 denotes a hydrogen atom and Rl represents a group -N \ 4 in which R3 and R4 form a piperidinyl ring as well as their salts such as for example sulfate.
The particularly preferred compound is made up by amino-6 dihydro-1,2 hydroxy-l imino-2 piperidino-4 pyrimidine also called "Minoxidil '~.
We call thickened medium having a viscosity greater than 0.4 Pa.s. and preferably between 1.5 Pa.s and 10 Pa.s.
The aqueous suspensi ~ n medium contains thickeners that do not cause agglomeration of the parties active ingredient. These thickeners are preferably selected from polyacrylic acids crosslinked by a polyfunctional agent such as more particularly products sold under the CARBOPOL trademark by the GOODRICH company such as Carbopol 910, 934, 934 P, 940, 941, 1342, or thickeners resulting from the interaction ionic of a cationic polymer constituted by a copolymer of cellulose or of a cellulose derivative grafted with a salt of water-soluble quaternary ammonium monomer and a anionic carboxylic polymer having absolute viscosity in dimethylformamide or methanol, to a concentration tion of 5 ~ and 30 ~ C, less than or equal to 30 x 10 3 Pa.s, ~ 2 ~
the thickener itself having an Epprecht-Drage viscosity, 3r module in 1% solution in water at 25 ~ C, higher or equal to 0.50 Pa.s.
The cationic polymer causes it to react with the anionic polymer is preferably chosen from hydroxyalkyl cellulose copolymers grafted by the radical with a water-soluble ammonium monomer salt quaternary chosen from methacryloylethyltrime salts-thylammonium, methacrylamidopropyltrimethylammonium, dimethyldiallylammonium. The anionic carboxylic polymer is preferably chosen from homopolymers of acid methacrylic having a molecular weight, determined by light scattering ~ greater than 20,000, copolymers methacrylic acid with a monomer chosen from C1-C4 alkyl acrylates or methacrylates, the derivatives acrylamide, maleic acid, an alkyl monomaleate in Cl-C ~ and the copolymers of ethylene and maleic anhydride.
The weight ratio between the cationic polymer and the anionic carboxylic polymer is between 1/5 and 5/1.
Particularly preferred thickeners are chosen from the products resulting from the interaction ion of a hydroxyethyl cellulose copolymer grafted with radical route with diallyldimethylammonium chloride such as products sold under the trademark CELQUAT L 200 or H 100 by the NATIONAL STARCH Company with:
- a copolymer of methacrylic acid and methyl methacrylate, having a viscosity, measured in solution in dimethylformamide at the concentration of 5 and at 30 ~ C, of the order of 15 x 10 3 Pa.s;
, ~ 2 ~
- a copolymer of methacrylic acid with monomaleate of ethyl presents an absolute viscosity, measured in solution in dimethylformamide at the concentration tration of 5P ~ and at 30 ~ C, of the order of 13 x 10 3 Pa.s;
- a methacrylic acid copolymer with butyl methacrylate, the absolute viscosity of which is measured dissolved in methanol at a concentration of 5% ~ is of the order of lO x lO 3 Pa.s;
- a copolymer of methacrylic acid with the acid maleique whose absolute viscosity, measured in solution in dimethylformamide at a concentration of 5 ~, is the order of l6 x lO 3 Pa.s.
The compounds of formula (I) in accordance with the invention;
tion are present in the composition in proportions between 0.2 and 5% by weight relative to the weight total of the composition, preferably between 0.3 and 3 ~ in weight.
The thickening agent is used in the compounds positions in proportions of between 0.4 and 2 ~ and depreference between 0.4 and 1.5% by weight, relative to the weight total of the composition.
These compositions may optionally contain in addition to the solvents in the proportions indicated above above, preservatives, complexing agents, dyes, basifying or acidifying agents, perfumes.
The pH of these compositions can vary between 4 and 9 and preferably between 7 and 8.5.
The particularly preferred composition includes 0.3 to 3% amino-6 dihydro-1,2 hydroxy-1 imino-2 piperi-4-dino pyrimidine in water containing 0.4 to l, S ~
8 - ;.

crosslinked polyacrylic acid having a molecular weight of

3,000,000 or a thickening agent consisting of hydroxyethyl cellulose copolymer grafted radically milk with diallyldimethylammonium chloride and methacrylic acid / methyl methacrylate copolymer and maximum 10 ~ by volume of ethyl alcohol.
The compositions according to the invention can be prepared, introducing into the thickened medium the compounds of formula (I) in powder form, the particles are as defined above, in sufficient proportions for all or part of the compounds of formula (I) passes into solution in the medium, in concentrations at least equal to the solubility limit the undissolved particles remaining in suspension in this mllleu.
Another embodiment may consist of prepare a saturated solution of the compounds of formula (I) and to be introduced in the form of particles as defined above another part of the compounds of formula (I) for form a suspension.
The proportions indicated are the proportions in composed of formula (I) present in the total composition either in dissolved form or suspended in the medium thick aqueous.
The treatment method for combating hair loss mainly involves applying on alopecic areas of the scalp and hair of a individual, a composition as defined above, by example after washing the scalp and hair using of a shampoo or shortly after shampooing.

The process according to the invention notably presents characteristics of a cosmetic process in the since it allows to treat hair or leather hairy in the cosmetic sense of the term, that is to say their wear the substances that it lacks and embellish them.
It also has characteristics of a therapeutic treatment insofar as it acts on the biological functions and mechanisms.
The following examples are intended to illustrate the invention without, however, having a limiting character tif.

The composition suspension medium is prepared next:
Crosslinked polyacrylic acid PM = 3 million, sold under CARBOPOL 934 trademark by GOODRICH 1.0 g Butoxy-2 ethanol 4.5 g Amino-2 methyl-2 propanol-l qs pH 8.5 Conservative qs Water qs 100.0 g 3 g are then added to this suspension medium.
amino-6 dihydro-1,2 hydroxy-l amino-2 piperidino-4 pyri-micronized midine, with an average particle diameter of 4 ~ um and then homogenized with the three-cylinder.
The Epprecht-Drage viscosity of the composition at 25 ~ C, module 4, is 7.2 Pa.s.
~ L ~ g ~

We prepare the composition suspension medium next:
CELQUAT L 200 (trademark! O, 7 g MA
Methacrylic acid copolymer /
methyl methacrylate 50/50 0.7 g MA
Ethyl alcohol 10 ~ in Vol.
Ethylene diaminotetracetic acid 0,02g Amino-2 methyl-2 propanol-l qs pH 7.5 Water qs 100.0 g Then added to this suspensi.on medium 3 g amino-6 dihydro-1,2 hydroxy-l imino-2 piperldino-4 pyri-midlne mlcronlse, with an average particle diameter of 4 ~ µm and it is homogenized with the three-cylinder.
The Epprecht-Drage viscosity of the composition at 25 ~ C, module 3, is 2.15 Pa.s.

The following composition is prepared:
Crosslinked polyacrylic acid PM: 3 million sold under the brand CARBOPOL 934 by the GOODRICH Company 1 g Propylene glycol 4.5 g Amino-2 methyl-2 propanol-l qs pH 7 Conservative qs Water qs 100 y ~ 2 ~
To this medium is then added 1 g of amino-6 1,2-dihydro-hydroxy-2-imino-4 piperidino-pyrimidine micronized, with an average particle diameter of less than 2 microns and then homogenized with a three-cylinder.
We note that part of the particles have dissolved in the medium (in ~ iron 0r25 g), the rest being suspension.
This composition applied to the scalp for 3 months at the rate of one treatment per day, allows note a clear increase in the number and density hair in the anagen phase of the order of 28 ~.
The Epprecht-Drage viscosity of the composition at 25 ~ C, module 4, is 7.8 Pa.s.

2 g of dlamino-6 are added to the middle of Example 3 1,2-dihydro-hydroxy-2-imino-4 piperidino-pyrimidine micronized with particle diameter less than 2 ~ µm and one homogeneous with the three-cylinder.
There is a net after 3 months of treatment increase in the number of hairs in the anagen phase (from around 30%).
The Epprecht-Drage viscosity of the composition at 25 ~ C, module 4, is 7.5 Pa.s.

0.5 g is added to the middle of Example 4 amino-6 dihydro-1,2 hydroxy-l imino-2 piperidino-4 pyrimi-micronized dine with particle diameter less than 2 ~ µm and it is homogenized with the three-cylinder.
We see, as before, an increase hair in the anagen phase.

.
~ 4 ~
Epprecht viscosity-drage of composition at 25 ~ C, module 4, is 7.5 Pa.s.

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Claims (30)

The realizations of the invention about which a right exclusive ownership or lien is claimed, are defined as follows: 1. Composition to induce and stimulate growth hair and reduce hair loss, based on derivatives of pyrimidine, characterized in that it comprises in an essentially aqueous and thickened medium, at least one compound corresponding to the general formula:
(I) in which R1 denotes a group in which R3 and R4, identical or different, represent a hydrogen atom or an alkyl or alkenyl group, lower alkylaryl or cycloalkyl, or R3 and R4 form with the nitrogen atom to which they are linked a heter-rocycle chosen from the group formed by the groups aziridinyl, azetidinyl, pyrrolidinyl, piperidinyl, hexahydroazepinyl, heptamethyleneimine, octamethyleneimine, morpholine and lower alkyl-4-piperazidinyl, the groups heterocyclic elements which can be substituted on the carbon atoms by one to three lower alkyl groups laughing, hydroxy or alkoxy; R2 denotes a hydrogen atom or an alkyl, alkenyl, alkylalkoxy, cycloalkyl group, aryl, alkylaryl, arylalkyl, alkylarylalkyle, alkoxyaryl-lower alkyl or haloarylalkyl, where one of its salts addition of cosmetically or pharmaceutically acids acceptable, in a concentration at least equal to the limit of solubility of the compound of formula (I) in the middle. 2. Composition according to claim 1, characterized by the fact that it contains as active substance, at minus a compound of formula (I) in which R3 and R4, identical or different, represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, alkenyl, lower alkylaryl or cycloalkyl, R2 having the aforementioned meaning, or one of its addition salts cosmetically or pharmaceutically acceptable acids. 3. Composition according to claim 1, characterized by the fact that the concentration of the compound of formula (I) is greater than the solubility limit so that the thickened aqueous medium comprises at least part of the compound of formula (I) in suspension in the form of a particle the. 4. Composition according to claim 3, characterized by the fact that the compound of formula (I) is present for the undissolved part in the form of particles having a average particle size less than 80 µm. 5. Composition according to claim 4, characterized by the fact that the average particle size is less than 20 µm. 6. Composition according to claim 4, characterized by the fact that the average particle size is less than 5 µm. 7. Composition according to claim 1, characterized by the fact that it contains as active substance at minus a compound of formula (I) in which R2 denotes a hydrogen atom, and R3 and R4 form with the nitrogen atom to which they are linked a piperidinyl ring, or one of its cosmetic or pharmaceutical acid addition salts acceptable. 8. Composition according to claim 7, characterized by the fact that the compound of formula (I) is amino-6 1,2-dihydro-1-hydroxy-2-imino-4 piperidino-pyrimidine. 9. Composition according to claims 1, 7 or 8, characterized in that the compound of formula (I) is present in micronized form. 10. Composition according to claims 1, 7 or 8, characterized in that the compound of formula (I) is present in the form of particles having a particle size average less than 5 µm. 11. Composition according to claim 1, characterized by the fact that it contains at least one thickening agent chosen from the group consisting of polyacrylic acids liques crosslinked with a polyfunctional agent. 12. Composition according to claim 1, characterized by the fact that it contains at least one thickening agent consisting of a product resulting from ionic interaction of a cationic polymer consisting of a copolymer of cellulose or a cellulose derivative grafted with a salt of water-soluble quaternary ammonium monomer and a anionic carboxylic polymer having a viscosity capil-absolute area in dimethylformamide or methanol, to a concentration of 5% and at 30 ° C, less than or equal to 30 x 10-3 Pa.s., the thickening agent having a viscosity Epprecht-drage, module 3, in 1% solution in water at 25 ° C
greater than or equal to 0.5 Pa.s. 13. Composition according to claim 12, character-laughed at by the fact that the thickening agent is chosen in the group formed by the products resulting from the ionic teraction of hydroxyalkyl cellulose copolymers radical grafted with a monomer salt water-soluble quaternary ammonium chosen from the group consisting of methacryloylethyltrimethylammo- salts nium, methacrylamidopropyltrimethylammonium, dimethyl-diallylammonium and an anionic carboxylic polymer chosen from the group consisting of homo-polymers of methacrylic acid having a molecular weight, determined by light scattering, greater than 20,000, copolymers of methacrylic acid with a monomer chosen from the group consisting of acrylates and metha-C1-C4 alkyl crylates, acrylamide derivatives, maleic acid, a C1-C4 alkyl monomaleate and the copolymers of ethylene and maleic anhydride. 14. Composition according to claim 13, character-sée by the fact that the thickening agent is chosen in the group formed by the products resulting from the interaction ionic acid of a hydroxyethyl cellulose copolymer grafted with radical route with diallyldimethylammonium chloride with:
- a copolymer of methacrylic acid and methyl methacrylate, having a capillary viscosity, measured in solution in dimethylformamide at the concentration 5% tration and at 30 ° C, of the order of 15 x 10-3 Pa.s;
- a copolymer of methacrylic acid with ethyl monomaleate with capillary viscosity absolute, measured in solution in dimethylformamide at the concentration of 5% and at 30 ° C, of the order of 13 x 10-3 Pa.s;
- a copolymer of methacrylic acid with butyl methacrylate whose absolute capillary viscosity, measured in solution in methanol at the concentration of 5%, is of the order of 10 x 10-3 Pa.s;
- a copolymer of methacrylic acid with the acid maleic whose absolute capillary viscosity, measured in solution in dimethylformamide at a concentration of 5%, is around 16 x 10-3 Pa.s. 15. Composition according to claims 11, 12 or 13, characterized by the fact that the thickened medium has a viscosity sity greater than 0.4 Pa.s. 16. Composition according to claims 11, 12 or 13, characterized by the fact that the thickened medium has a viscosity between 1.5 Pa.s. and 10 Pa.s. 17. Composition according to claims 11, 12 or 13, characterized by the fact that the thickening agent is present in a proportion of between 0.4 and 2% in weight, relative to the total weight of the composition. 18. Composition according to claims 11, 12 or 13, characterized by the fact that the thickening agent is present in a proportion of between 0.4 and 1.5% in weight, relative to the total weight of the composition. 19. Composition according to claim 1, characterized by the fact that the aqueous medium contains at least one organic solvent in a proportion of less than 20% by weight, relative to the total weight of the composition. 20. Composition according to claim 19, character-sée by the fact that the organic solvent is chosen in the group consisting of C1-C4 lower alcohols, alkylene glycols and the alkyl ethers of alkylene glycols and dialkylene glycols. 21. Composition according to claims 19 or 20, characterized by the fact that the organic solvent is present in a proportion of less than 10% by weight. 22. Composition according to claims 1, 7 or 8, characterized in that the compound of formula (I) is present in a proportion between 0.2 and 5% in weight, relative to the total weight of the composition. 23. Composition according to claims 1, 7 or 8, characterized in that the compound of formula (I) is present in a proportion of between 0.3 and 3% in weight, relative to the total weight of the composition. 24. Composition according to claim 1, characterized by the fact that it also contains at least one adjuvant cosmetic chosen from the group of agents preservatives, complexing agents, dyes, alkalizing or acidifying agents and perfumes. 25. Composition according to claim 1, characterized by the fact that it has a pH between 4 and 9. 26. Composition according to claim 25, character-sed by the fact that the pH is between 7 and 8.5. 27. Composition according to claim 1, characterized by the fact that it comprises from 0.3 to 3% of 6-amino dihydro-1,2-hydroxy-1 imino-2 piperidino-4 pyrimidine in water containing 0.4 to 1.5% crosslinked polyacrylic acid having a molecular weight of 3,000,000 or a thickening agent health consisting of the hydroxyethyl cellulose copolymer radically grafted with diallyldimide chloride thylammonium and the methacrylic acid / methacry- copolymer methyl late and a maximum of 10% by volume of ethyl alcohol than. 28. Composition according to claims 1, 7 or 8, characterized by the fact that it is intended to be used used as a medicine to treat the fall of hair, induction and stimulation of their growth. 29. Method for cosmetic treatment of the scalp and hair, characterized by the fact that one applies at least one composition on the scalp or the hair as defined in claims 1, 7 or 8. 30. Process for treating the scalp and hair to combat hair loss, and induce or stimulate their growth, characterized by applied to the scalp or hair at minus a composition as defined in the claims 1, 7 or 8.