Process for depigmenting keratin materials using thiopyridinone compounds
11052028 · 2021-07-06
Assignee
Inventors
Cpc classification
A61K8/4933
HUMAN NECESSITIES
International classification
Abstract
The invention relates to cosmetic processes and compositions for depigmenting, lightening and/or whitening keratin materials, in particular the skin, which comprises the application of a cosmetic composition comprising thiopyridinone compounds to keratin materials.
Claims
1. A depigmenting or lightening composition for at least one human keratin material selected from the group consisting of body skin of human beings, face skin of human beings, lips of human beings, and scalp of human beings, in a physiologically acceptable medium which is compatible with at least one of body skin of human beings, face skin of human beings, lips of human beings, and scalp of human beings, comprising from 0.1 to 10% by weight relative to the total weight of the composition of at least one compound of formula (Ia) ##STR00057## or its tautomeric form of formula (I′a) ##STR00058## wherein R.sub.1 denotes a hydrogen atom or a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, when R.sub.1 denotes a hydrogen atom, then R.sub.2 denotes a radical chosen from unsaturated C.sub.2-C.sub.20 alkyls, cyclic C.sub.7 alkyl radicals, saturated linear C.sub.1-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, saturated branched C.sub.3-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, and (C.sub.1-C.sub.20)alkylaryls substituted with one or more identical or different —OR.sub.3 groups, R.sub.3 denoting a hydrogen atom or a saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 or unsaturated C.sub.2-C.sub.5 group; when R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, then R.sub.2 denotes a radical chosen from a saturated branched C.sub.3-C.sub.12 or cyclic C.sub.3-C.sub.7 alkyl group, optionally interrupted with one or more oxygen atoms, and/or optionally containing one or more identical or different —OR.sub.3 groups, and R.sub.3 denotes a hydrogen atom or an optionally hydroxylated, saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 hydrocarbon group, or a salt thereof, optical isomer thereof or racemate thereof, wherein the composition depigments or lightens a keratin material after application to the keratin material.
2. The composition of claim 1, wherein when R.sub.1 denotes a hydrogen atom, then R.sub.2 denotes a radical chosen from unsaturated C.sub.2-C.sub.20 alkyls, saturated linear C.sub.1-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, saturated branched C.sub.3-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, and (C.sub.1-C.sub.6)alkylphenyls substituted with one or more identical or different —OR.sub.3 groups, R.sub.3 denoting a hydrogen atom or a saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 or unsaturated C.sub.2-C.sub.5 group; when R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, then R.sub.2 denotes a radical chosen from a saturated branched C.sub.3-C.sub.12 or cyclic C.sub.3-C.sub.7 alkyl group, optionally interrupted with one or more oxygen atoms, and/or optionally containing one or more identical or different —OR.sub.3 groups, and R.sub.3 denotes a hydrogen atom or an optionally hydroxylated, saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 hydrocarbon group.
3. The composition of claim 1, wherein when R.sub.1 denotes a hydrogen atom, then R.sub.2 denotes a radical chosen from saturated linear C.sub.1-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, saturated branched C.sub.3-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, and (C.sub.1-C.sub.6)alkylphenyls substituted with one or more identical or different —OR.sub.3 groups, R.sub.3 denoting a hydrogen atom or a saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 or unsaturated C.sub.2-C.sub.5 group; when R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, then R.sub.2 denotes a radical chosen from a saturated branched C.sub.3-C.sub.12 or cyclic C.sub.3-C.sub.7 alkyl group, optionally interrupted with one or more oxygen atoms, and/or optionally containing one or more identical or different —OR.sub.3 groups, and R.sub.3 denotes a hydrogen atom or an optionally hydroxylated, saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 hydrocarbon group.
4. The composition of claim 1, wherein the compound is N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N,N-bis(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(2,3-dihydroxypropyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(1,3-dihydroxypropan-2-yl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(1,3-dihydroxypropan-2-yl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-ethyl-N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; or N-[2-(2-hydroxyethoxy)ethyl]-2-thioxo-1,2-dihydropyridine-3-carboxamide.
5. The composition of claim 1, wherein R.sub.1 denotes a hydrogen atom.
6. The composition of claim 1, wherein R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups.
7. The composition of claim 1, wherein the physiologically acceptable medium is compatible with body skin of human beings.
8. The composition of claim 1, wherein the physiologically acceptable medium is compatible with lips of human beings.
9. The composition of claim 1, wherein the compound is N-ethyl-N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide.
10. The composition of claim 1, wherein the composition comprises from 0.5 to 5% by weight relative to the total weight of the composition of at least one compound of formula (Ia).
11. The composition of claim 1, wherein the composition comprises from 0.5 to 3% by weight relative to the total weight of the composition of at least one compound of formula (Ia).
12. The composition of claim 1, which comprises 0.1 to 5% by weight of the compound of formula (Ia) or its tautomeric form of formula (I′a).
13. The composition of claim 12, wherein when R.sub.1 denotes a hydrogen atom, then R.sub.2 denotes a radical chosen from unsaturated C.sub.2-C.sub.20 alkyls, saturated linear C.sub.1-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, saturated, branched C.sub.3-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, and (C.sub.1-C.sub.6)alkylphenyls substituted with one or more identical or different —OR.sub.3 groups, R.sub.3 denoting a hydrogen atom or a saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 or unsaturated C.sub.2-C.sub.5 group; when R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, then R.sub.2 denotes a radical chosen from a saturated branched C.sub.3-C.sub.12 or cyclic C.sub.3-C.sub.7 alkyl group, optionally interrupted with one or more oxygen atoms, and/or optionally containing one or more identical or different —OR.sub.3 groups, and R.sub.3 denotes a hydrogen atom or an optionally hydroxylated, saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 hydrocarbon group.
14. The composition of claim 12, wherein when R.sub.1 denotes a hydrogen atom, then R.sub.2 denotes a radical chosen from saturated linear C.sub.1-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, saturated branched C.sub.3-C.sub.20 alkyls optionally substituted with one or more identical or different —OR.sub.3 groups, and (C.sub.1-C.sub.6)alkylphenyls substituted with one or more identical or different —OR.sub.3 groups, R.sub.3 denoting a hydrogen atom or a saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 or unsaturated C.sub.2-C.sub.5 group; when R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups, then R.sub.2 denotes a radical chosen from a saturated branched C.sub.3-C.sub.12 or cyclic C.sub.3-C.sub.7 alkyl group, optionally interrupted with one or more oxygen atoms, and/or optionally containing one or more identical or different —OR.sub.3 groups, and R.sub.3 denotes a hydrogen atom or an optionally hydroxylated, saturated linear C.sub.1-C.sub.5 or branched C.sub.3-C.sub.5 hydrocarbon group.
15. The composition of claim 12, wherein the compound is N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N,N-bis(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(2,3-dihydroxypropyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(1,3-dihydroxypropan-2-yl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-(1,3-dihydroxypropan-2-yl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; N-ethyl-N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide; or N-[2-(2-hydroxyethoxy)ethyl]-2-thioxo-1,2-dihydropyridine-3-carboxamide.
16. The composition of claim 12, wherein R.sub.1 denotes a hydrogen atom.
17. The composition of claim 12, wherein R.sub.1 denotes a saturated linear C.sub.1-C.sub.10 or branched C.sub.3-C.sub.10 or unsaturated C.sub.2-C.sub.10 alkyl group, optionally substituted with one or more —OR.sub.3 groups.
18. The composition of claim 12, wherein the physiologically acceptable medium is compatible with body skin of human beings.
19. The composition of claim 12, wherein the physiologically acceptable medium is compatible with lips of human beings.
20. The composition of claim 12, wherein the compound is N-ethyl-N-(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide.
Description
EXAMPLES 1 to 4
Demonstration of the Activity on Constitutive Melanogenesis
(1) A biological test demonstrated the depigmenting activity of 7 compounds of formula (I) (compounds 2, 7, 12, 16, 19, 21 and 27).
(2) The modulatory effect of each compound on melanogenesis was measured according to the method described in FR-A-2734825 and also in the article by R. Schmidt, P. Krien and M. Regnier, Anal. Bichem., 235(2), 113-18,1996. This test is carried out on a coculture of keratinocytes and melanocytes.
(3) For the compounds tested, the following were determined: the cytotoxicity, by estimating leucine incorporation, the inhibitory activity on melanin synthesis, by estimating the ratio of thiouracil incorporation to leucine incorporation, relative to 100% of the control (the control corresponds to the test carried out without test compound). The IC50 values (concentration for which 50% of the melanin synthesis is inhibited) were determined.
(4) The test was also carried out with arbutin, niacinamide and kojic acid, which are known depigmenting compounds.
(5) The results are collated in the following table:
(6) TABLE-US-00003 Cytotoxicity Compound on coculture IC50 Arbutin Non-cytotoxic Not attained (or greater than 500 μM) Kojic acid 100 μM Not attained (or greater than 500 μM) Niacinamide Non-cytotoxic Not attained Compound 2
(7) Compounds 2, 7, 12, 16, 19, 21 and 27 therefore demonstrate their efficacy in inhibiting melanogenesis and are, moreover, more effective than arbutin, kojic acid and niacinamide.
(8) Compound 2 is the most effective compound.
EXAMPLE 5
(9) A depigmenting gel for the skin is prepared, comprising (% by weight):
(10) TABLE-US-00004 Compound 2 2% Carbomer (Carbopol 981 from Lubrizol) 1% preservative qs water qs 100%
(11) When applied to the skin, the composition makes it possible to fade out brown marks.
(12) A similar composition is prepared with compound 3 or compound 11 or compound 16.