STABILIZATION OF THIOPYRIDINONE COMPOUND AND COMPOSITION COMPRISING THE LATTER

Abstract

STABILIZATION OF THIOPYRIDINONE COMPOUNDS AND COMPOSITIONS COMPRISING THE LATTER The present invention relates to a composition comprising: (a) at least one thiopyridinone compound; and (b) at least one compound selected from ergothioneine and its derivatives. The present invention may provide a composition including (a) one or more thiopyridinone compounds with increased stability of the (a) thiopyridinone compound(s) over time, particularly even when the composition is maintained for a relatively long period at elevated temperature. Figure for abstract: none

Description

Title of the invention: STABILIZATION OF THIOPYRIDINONE COMPOUND AND COMPOSITION COMPRISING THE LATTER technical field

[0001] The present invention relates to the stabilization of a thiopyridinone compound in a composition including the thiopyridinone compound. STATE OF THE ART

[0002] At various times in their lives, some people notice the appearance on their skin, and more particularly on their face and hands, of browner and / or more colored spots, which give their skin a heterogeneous appearance. These spots are primarily due to a high concentration of melanin in the keratinocytes located on the surface of the skin.

[0003] The use of harmless topical depigmentation substances with good efficacy is particularly desired for the purpose of treating pigmentation spots.

[0004] For example, arbutin, niacinamide and kojic acid are known as skin depigmenting agents.

[0005] Furthermore, WO2017 / 102349 discloses a new depigmenting or bleaching agent, namely, a thiopyridinone compound. The thiopyridinone compound can exhibit strong depigmenting or bleaching effects by reducing melanin production. DISCLOSURE OF THE INVENTION

[0006] However, it has been discovered that a thiopyridinone compound tends to become unstable in a composition over time, particularly when the composition including the thiopyridinone compound is maintained for a relatively long period at a high temperature.

[0007] Thus, an objective of the present invention is to propose a composition including thiopyridinone compound(s) exhibiting increased stability of the thiopyridinone compound(s) over time, in particular when the composition is maintained for a relatively long period of time at high temperature.

[0008] The above objective can be achieved by a composition, preferably a cosmetic composition, and more preferably a cosmetic composition for the skin, comprising: a. at least one compound selected from the compounds of formula (I) below, the tautomers of formula (!') below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures:

[0009] [Chem.l] (H

[0010] in which

[0011] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-Cio or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3,

[0012] and

[0013] - R2 denotes a radical chosen from a. a hydrogen atom, b. a linear saturated CrCi2 or C3-Ci2 branched or C3-C8 cyclic hydrocarbon group, optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in the C1-C8 group, and a. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals

[0014] in which

[0015] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-Cio or a branched alkyl group in the form of C3-CiO;

[0016] and

[0017] (b) at least a second compound selected from ergothioneine and its derivatives.

[0018] It may be preferable that:

[0019] - Ri of formula (I) and (!') represents a hydrogen atom;

[0020] or

[0021] - Ri of formula (I) and (!') represents a linear alkyl group (in C1-C10) or a branched alkyl group (in C3-Ci0), in particular a linear alkyl group (in Ci-C6) or a branched alkyl group (in C3-C6), such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably ethyl, in particular said alkyl group of Rin' is not substituted.

[0022] It may be preferable that:

[0023] - R2 of formula (I) and (I') represents a hydrogen atom;

[0024] or

[0025] - R2 of formula (I) and (I') represents a linear alkyl group (in C1-C10) or a branched alkyl group (in C3-Ci0), in particular a linear alkyl group (in Ci-C6) or a branched alkyl group (in C3-C6), preferably a methyl, ethyl, n-pentyl, n-nonyl, isobutyl group, more preferably methyl or ethyl; said alkyl group of R2 not being substituted.

[0026] It may be preferable that:

[0027] - R2 of formula (I) and (I') represents a linear alkyl group (in Ci-CiO) or a branched alkyl group (in C3-Ci0), in particular a linear alkyl group (in Ci-C6) or a branched alkyl group (in C3-C6), preferably a methyl, ethyl, n-pentyl, n-nonyl, isobutyl group, more preferably methyl or ethyl group; said alkyl group being substituted by one or more groups selected from i), ii), iii) and iv) as defined above, preferably said alkyl group being substituted by one or two groups selected from i), ii) and iii), more preferably by one or two groups selected from i) and iii), better substituted by a group iii) such as carboxy.

[0028] It may be preferable that:

[0029] - R2 of formula (I) and (I') represents a cycloalkyl group (at C3-C8), preferably a cycloalkyl group (in C5-C7) such as cyclohexyl;

[0030] or

[0031] - R2 of formula (I) and (I') represents an optionally C5-Ci2 aryl group substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in CrC8, preferably a phenyl group in particular unsubstituted.

[0032] It may be preferable that:

[0033] - R3 of formula (I) and (I') represents a hydrogen atom;

[0034] or

[0035] - R3 of formula (I) and (!') represents a linear saturated alkyl group in Ci-Cio or branched in C3-C10; in particular a linear alkyl group (in Ci-C6) or a branched alkyl group (in C3-C6), preferably an alkyl group (in CrC4) such as a methyl group.

[0036] It may be more preferable that:

[0037] - Ri of formula (I) and (!') represents a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the C1-C6 range or branched in the C3-C6 range, optionally substituted by one or more groups, which may be the same or different, chosen from i. -O-R3, and ii. -S-R3,

[0038] preferably optionally substituted by one or more groups i);

[0039] - R2 of formula (I) and (!') represents a radical chosen from a. a hydrogen atom, and b. a linear saturated hydrocarbon group in C1-C10 or branched in C3-C10 or cyclic in C3-C8 such as in C5-C6, optionally substituted by one or more groups, which may be the same or different, selected from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. a phenyl group optionally substituted by one or more hydroxyl groups and / or by one or more C1-C4 alkoxy radicals such as methoxy,

[0040] preferably substituted by one or more groups selected from i) and iii), preferably iii) such as carboxy; and

[0041] - R3 of formula (I) and (!') represents a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the C1-C6 configuration or a branched C3-C6 configuration,

[0042] Preferably, the compounds of formula (I) and the tautomer (I'), their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures, have the following meanings:

[0043] - Ri of formula (I) and (!') represents a radical chosen from: a. a hydrogen atom, and b. a linear saturated alkyl group in C1-C4 or branched in C3-C4 optionally substituted by one or more groups, which may be identical or different, chosen from i) -OR3jplus preferably unsubstituted;

[0044] - R2 of formula (I) and (!') represents a radical chosen from a. a hydrogen atom, and b. a linear saturated hydrocarbon group in C1-C10 or branched in C3-C10 or cyclic in C3-C8 such as in C5-C6, optionally substituted by one or more groups, which may be identical or different, selected from

[0045] i) -O-R3,

[0046] iii) -C(O)-O-R3, and

[0047] iv) a C5-C12 aryl group, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in C1-C4; and

[0048] - R3 of formula (I) and (!') represents a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in C1-C4 or branched in C3-C4 such as methyl or ethyl.

[0049] The (a) first compound may be selected from compounds 1 to 24 below, their tautomers, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures, in particular compounds 1, 2, 4, 6, 7, 9, 11, 12, 14, 15, 16, 17, 18, 19, 20 or 21, more particularly 1, 9, 16, 18, 19, 20 or 21, preferably 18, 19, 20 or 21, and more preferably 20:

[0050] [Tables 1] No. Structure Chemical Name 1 hh H N-ethyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 2 ; --------X x \ N-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 3 & 0 N-octyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 4 l A. ' O '■‘il N-benzyl-2-thioxo-1,2-dihydrop yridine- 3 -c arboxamide 5 .-Z % / / H / \ X \ X % N-phényl-2-thioxo-1,2-dihydrop yridine- 3 -c arboxamide 6 X X-X H 5 H XX H N-cyclohexyl-2-thioxo-1,2-dihy dropyridine-3-carboxamide 7 ^i^xy'" N- [2- (4-méthoxyphény l)éthy 1] -2-thioxo-1,2-dihydropyridine-3-carboxamide 8 hv x .Av VY'X '^x'' N-(2-méthylpropyl)-2-thioxo-1,2 -dihy drop yridine- 3 -c arboxamide 9 N-pentyl-2-thioxo-1,2-dihydropy ridine- 3 -c arboxamide 10 N-nonyl-2-thioxo-1,2-dihydropy ridine- 3 -c arboxamide Cl A f r ~ ' - 11 & A. f '"A >;x ...-^ X "* ''"'X X H N-(2-hydroxyéthyl)-2-thioxo-1,2 -dihy dropyridine- 3 -c arboxamide 12 y? ,X x'lX xXV: •' ■ ■ k. 1 H N,N-diéthyl 2-mercaptonicotina mide 13 x xx '''N—s k k '"■■"■■OH "1C 'X \ H N-éthyl-N-(2-hydroxyéthyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide 14 O^A^V N-(2,3-dihydroxypropyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide 15 N-( 1,3-dihydroxypropan-2-yl)-2-thioxo-1,2-dihydropyridine-3-carboxamide OH 0 •■■■" 'X>X' ' x / ^ïX'' "Vj 16 H / N-[(2-thioxo-1,2-dihydropyridin 3-yl)carbonyl]ethyl alaninate 17 AY • X N-[(2-thioxo-1,2-dihydropyridin 3-yl)carbonyl]ethyl phenyl alaninate 18 N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate '.,: VY : (-,. --^ 1' X Au A is S § 19 N-[(2-thioxo-1,2-dihydropyridin 3-yl)carbonyl]ethyl glycinate 20 N-[(2-thioxo-1,2-dihydropyridin 3-yl)carbonyl]glycine 21 f 'Xy' L Jk ch, cm N N-methyl-N-[(2-thioxo-1,2-dihy dropyridin-3-yl)carbonyl]glycine 22 yk ,,y YY v $ O; N,N-bis(2-hydroxyethyl)-2-thioxo-1,2-dihydropyridine-3-carboxamide 23 N-(3-methoxypropyl)-2-thioxo-1,2-dihydropyridine-3-carboxami of 24 M> -'•'x N-butyl-2-thioxo-1,2-dihydropyr idine-3-carboxamide

[0051] The quantity of the (a) first compound(s) in the composition according to the present invention can be from 0.001% to 10% by weight, preferably from 0.005% to 5% by weight, and more preferably from 0.01% to 3% by weight, relative to the total weight of the composition.

[0052] The (b) second compound can be represented by the following chemical formula (II):

[0053] (II)

[0054] in which:

[0055] - X represents a group -O-R', -OM or -NR'R";

[0056] - R, R' and R" represent, simultaneously or independently of each other, a hydrogen atom, an alkyl, alkenyl or acyl group in the form Ci-Ci8, the alkyl, alkenyl or acyl group being linear or branched, optionally substituted by at least one substituent selected from the hydroxyl group, possibly esterified, halogen atoms, the carboxyl group and its derivatives, and the amine group and its derivatives, and optionally containing in the chain at least one heteroatom such as O and S; and

[0057] - M represents a cation such as a metallic cation.

[0058] It may be preferable that the groups R, R' and R" of the chemical formula (II) above designate, simultaneously or independently of each other, a hydrogen atom or an ethyl, acetyl or acyl group, and preferably R designates a hydrogen atom or an ethyl, acetyl or acyl group, and X designates NH2.

[0059] It is more preferable that (b) the second compound be ergothioneine.

[0060] The quantity of the (b) second compound(s) in the composition according to the present invention can be from 0.001% to 10% by weight, preferably from 0.005% to 10% by weight, more preferably from 0.01% to 5% by weight, relative to the total weight of the composition.

[0061] The present invention also relates to a cosmetic process, preferably a whitening process, for a keratinous material, preferably skin, comprising the step of:

[0062] application on keratinous material of the composition according to the present invention.

[0063] Another aspect of the present invention is the use of at least one (b) second compound selected from ergothioneine and its derivatives in a composition comprising (a) at least one first compound selected from the compounds of formula (I) below, the tautomers of formula (I1) below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures:

[0064] [Chem.3] H 0) (H

[0065] in which

[0066] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-Cio or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3,

[0067] and

[0068] - R2 denotes a radical chosen from a. a hydrogen atom, b. a saturated hydrocarbon group, linear in C1-C12 or branched in C3-C12 or cyclic in C3-C8, optionally substituted by one or more groups, which may be the same or different, chosen from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in CrC8, and a. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in Ci-C8

[0069] in which

[0070] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the C1-C10 configuration or a branched C3-C10 configuration.

[0071] in order to stabilize the (a) first compound(s). Best embodiment of the invention

[0072] After extensive research, the inventors discovered that it is possible to provide a composition including a thiopyridinone compound or thiopyridinone compounds exhibiting increased stability of the thiopyridinone compound(s) over time, particularly even when the composition is maintained for a relatively long period of time at high temperature.

[0073] Thus, the composition according to the present invention comprises:

[0074] (a) at least a first compound selected from the compounds of formula (I) below below, the tautomers of formula (T) below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures (hereafter, the compound of formula (I) or (I1) is called the "first compound" or "thiopyridinone compound"):

[0075] [Chem.4] O O G)

[0076] in which

[0077] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-CiO or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3,

[0078] and

[0079] - R2 denotes a radical chosen from a. a hydrogen atom, b. a linear saturated CrCi2 or C3-Ci2 branched or C3-C8 cyclic hydrocarbon group, optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals, and a. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals

[0080] in which

[0081] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in Ci-Cio or branched in C3-CiO;

[0082] and

[0083] (b) at least a second compound selected from ergothioneine and its derivatives.

[0084] The composition according to the present invention may exhibit increased stability of (a) thiopyridinone compound in this one.

[0085] In other words, the composition according to the present invention can increase the stability of (a) the thiopyridinone compound therein. The "stability" of (a) the thiopyridinone compound can be determined by the change in the amount of (a) the thiopyridinone compound in the composition according to the present invention over a certain period of time. Increased "stability" means that the change in the amount of (a) the thiopyridinone compound over time is more limited.

[0086] The composition according to the present invention may exhibit increased stability of the (a) thiopyridinone compound therein, even when the composition is maintained for a relatively long period of time such as two weeks and two months at a high temperature such as 45 °C and 55 °C.

[0087] Consequently, the composition according to the present invention can be stored for a long period of time even under hot conditions.

[0088] Furthermore, the increased stability of (a) thiopyridinone compound may offer improved or enhanced bioavailability of (a) thiopyridinone compound, which can act as a depigmenting or bleaching agent. Therefore, the composition according to the present invention may offer enhanced or improved depigmenting or bleaching effects.

[0089] The composition, use and similar properties according to the present invention will be described in detail below. [Composition]

[0090] The composition according to the present invention comprises: a. at least one first compound (thiopyridinone compound); and b. at least one second compound chosen from ergothioneine and its derivatives.

[0091] The (a) first compound and the (b) second compound, as well as the other features of the composition according to the present invention, will be explained below.

[0092]

[0093]

[0094] (First compound) The composition according to the present invention comprises (a) at least one first compound. Two or more (a) first compounds may be used in combination. Thus, a single type of (a) first compound or a combination of different types of (a) first compounds may be used. The (a) first compound is chosen from the compounds of formula (I) below, the tautomers of formula (!') below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates and their mixtures: [Chem. 5] H H (I)

[0095]

[0096]

[0097]

[0098] in which - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-CiO or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3, And - R2 denotes a radical chosen from a. a hydrogen atom, b. a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8, optionally substituted by one or more groups, which may be the same or different, chosen from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in CrC8, and a. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in Ci-C8

[0099] in which

[0100] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in Ci-Cio or branched in C3-Ci0.

[0101] Hereinafter, within the meaning of the present invention and unless otherwise indicated:

[0102] - a hydrocarbon group "saturated, linear in C1-C12 or branched in C3-C12" is equivalent to a "linear (C1-C12) or branched (C3-Ci2) alkyl group" which corresponds to a saturated hydrocarbon-based group, linear in C1-C12 or branched in C3-Ci2, preferably a linear in C1-C10 or branched in C3-Ci0 hydrocarbon-based group, and more preferably a linear in Ci-C6 or branched in C3-C6 hydrocarbon-based group; Preferably, the linear or branched groups may be selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl; More preferably, the saturated alkyl groups, linear or branched, can be chosen from methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl and octyl, such as methyl, ethyl, n-pentyl, n-nonyl and isobutyl;

[0103] - a saturated hydrocarbon group "cyclic in C3-C8" is a cycloalkyl group mono- or bicyclic containing 3 to 8 carbon atoms, and is notably a monocyclic cycloalkyl group in C5 to C7 such as a cyclohexyl group,

[0104] - an "alkoxy radical" is an alkyl-oxy radical for which the alkyl radical is a linear or branched hydrocarbon-based radical in CrCi6, and preferably in Ci-C8;

[0105] - when the alkoxy group is optionally substituted, this implies that the group alkyl is optionally substituted as defined above;

[0106] - an "aryl" group represents a carbon-based, monocyclic or bicyclic, fused or not, comprising from 5 to 12 carbon atoms, preferably from 6 to 10 carbon atoms, and in which at least one ring is aromatic; preferably, the aryl radical is a phenyl, biphenyl, naphthyl group, more preferably phenyl;

[0107] - the expression "at least one" is equivalent to the expression "one or more"; and

[0108] - the term "included" for a range of concentrations means that the limits of this ranges are included in the defined range.

[0109] The salts of compounds of formula (I), (I'), (II), or (II') as defined below include conventional non-toxic salts of said compounds, such as those formed from an organic or inorganic acid or an organic or inorganic base.

[0110] Examples of salts of compounds of formula (I), (I'), (II) or (II') include:

[0111] the salts obtained by adding the compound of formula (I) or (II) to:

[0112] - a mineral base, such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonium hydroxide, magnesium hydroxide, lithium hydroxide, and sodium, potassium or calcium carbonate or hydrogen carbonate, for example;

[0113] or

[0114] - an organic base such as a primary, secondary or tertiary alkylamine, by Examples include triethylamine and butylamine. This primary, secondary, or tertiary alkylamine may contain one or more nitrogen and / or oxygen atoms and may thus include, for example, one or more alcohol groups. Notable examples include 2-amino-2-methylpropanol, ethanolamine, triethanolamine, 2-dimethylaminopropanol, 2-amino-2-(hydroxymethyl)-1,3-propanediol, and 3-(dimethylamino)propylamine.

[0115] Other examples include amino acid salts, for instance lysine, arginine, guanidine, glutamic acid, and aspartic acid. Advantageously, the salts of compounds of formula (I) or (II) (when they include a carboxy group) can be selected from alkali or alkaline earth metal salts such as sodium, potassium, calcium, or magnesium salts and ammonium salts.

[0116] A "salt of an organic or inorganic acid" is more particularly chosen from among the salts chosen from a salt derived from i) hydrochloric acid HCl, ii) hydrobromic acid HBr, iii) sulfuric acid H2SO4, iv) alkylsulfonic acids: Alk-S(O)2OH such as methanesulfonic acid and ethanesulfonic acid; v) arylsulfonic acids: Ar-S(O)2OH such as benzenesulfonic acid and toluenesulfonic acid; vi) citric acid; vii) succinic acid; viii) tartaric acid; ix) lactic acid; x) alkoxysulfinic acids: Alk-OS(O)OH such as methoxysulfinic acid and ethoxysulfinic acid; xi) aryloxysulfinic acids such as tolueneoxysulfinic acid and phenoxysulfinic acid; xii) phosphoric acid H3PO4; xiii) acetic acid CH3C(O)OH; xiv) triflic acid CF3SO3 H; and xv) tetrafluoroboric acid HBF4.

[0117] Acceptable solvates of the compounds described in the patent memorandum include conventional solvates such as those formed during the preparation of said compounds due to the presence of solvents. Examples include solvates due to the presence of water or linear or branched alcohols, such as ethanol or isopropanol.

[0118] Optical isomers are, in particular, enantiomers and diastereomers.

[0119] Compound (I') is the tautomeric form of compound (I) when a tautomeric equilibrium exists according to the following scheme:

[0120] According to one embodiment of the present invention, Ri represents a hydrogen atom.

[0121] [Chem 6

[0122] According to another embodiment of the present invention, Ri represents a linear (Ci-Ci) or branched (C3-C10) alkyl group, in particular a linear (Ci-C6) or branched (C3-C6) alkyl group, preferably methyl, ethyl, n-pentyl, n-nonyl, or isobutyl, more preferably ethyl. In particular, said alkyl group of Ri is unsubstituted.

[0123] According to one embodiment of the present invention, R2 represents a hydrogen atom.

[0124] According to another embodiment of the present invention, R2 represents a linear (C1-C10) or branched (C3-C10) alkyl group, in particular a linear (C1-C6) or branched (C3-C6) alkyl group, preferably a methyl, ethyl, n-pentyl, n-nonyl, isobutyl group, more preferably methyl or ethyl; said alkyl group of R2 not being substituted.

[0125] According to another embodiment of the present invention, R2 represents a linear (C1-C10) or branched (C3-C10) alkyl group, in particular a linear (C1-C6) or branched (C3-C6) alkyl group, preferably methyl, ethyl, n-pentyl, n-nonyl, or isobutyl, more preferably methyl or ethyl; said alkyl group being substituted by one or more groups selected from i), ii), iii), and iv) as defined above. Preferably, said alkyl group being substituted by one or two groups selected from i), ii), and iii), more preferably by one or two groups selected from i) and iii), better substituted by a group iii) as a carboxy.

[0126] Another variant for the radical R2 is that said alkyl group is substituted by a group iv) in particular substituted by a phenyl group.

[0127] According to another embodiment of the present invention, R2 represents a cycloalkyl group (in C3-C8), preferably a cycloalkyl group (in C5-C7) such as cyclohexyl.

[0128] According to another embodiment of the present invention, R2 represents a C5-Ci2 aryl group optionally substituted by one or more hydroxyl groups and / or by a or several CrC8 alkoxy radicals, preferably with a particularly unsubstituted phenyl group.

[0129] According to one embodiment, R3 represents a hydrogen atom.

[0130] According to another embodiment, R3 represents a saturated, linear alkyl group in Ci-Cio or branched in C3-Ci0; in particular a linear (Ci-C6) or branched (C3-C6) alkyl group, preferably an alkyl group (CrC4) such as the methyl group.

[0131] Preferably, the compounds of formula (I) and the tautomer (!') or their salts, their optical isomers, their racemates, and / or their solvates such as their hydrates, alone or in mixture, have the following meanings:

[0132] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the C1-C6 configuration or a branched C3-C6 configuration optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3,

[0133] preferably optionally substituted by one or more groups i);

[0134] - R2 denotes a radical chosen from a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1O or branched in C3-C1O or cyclic in C3-C8 such as C5-C6 optionally substituted by one or more groups, which may be identical or different, chosen from: i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. a phenyl group optionally substituted by one or more hydroxyl groups and / or by one or more Ci-C4 alkoxy radicals such as methoxy,

[0135] preferably substituted by one or more groups selected from i) and iii), preferably iii) such as carboxy; and

[0136] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the C1-C6 configuration or a branched C3-C6 configuration.

[0137] Preferably, the compounds of formula (I) and the tautomer (!') or their salts, their optical isomers, their racemates, and / or their solvates such as their hydrates, alone or in mixture, have the following meanings:

[0138] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in C1-C4 or branched in C3-C4 optionally substituted by one or more groups, which may be identical or different, chosen from i) -OR3jplus preferably unsubstituted;

[0139] - R2 denotes a radical chosen from a. a hydrogen atom; and b. a linear saturated hydrocarbon group in C1-C1 or branched in C3-C10 or cyclic in C3-C8 such as in C5-C6, optionally substituted by one or more groups, which may be identical or different, selected from

[0140] i) -O-R3,

[0141] iii) -C(O)-O-R3,

[0142] iv) an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals at C1-C4; and

[0143] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated CrC4 or C3-C4 branched alkyl group such as methyl or ethyl.

[0144] Preferably, the compounds of formula (I) and the tautomer (!') or their salts, their optical isomers, their racemates, and / or their solvates such as their hydrates, alone or in mixture, have the following meanings:

[0145] Ri is a hydrogen atom; and

[0146] R2 denotes a radical chosen from

[0147] a) a hydrogen atom, and

[0148] b) a saturated hydrocarbon group, linear in C1-C5 or branched in C3-C5 or cyclic in C3-C8 such as in C5-C6, may be identical or different, chosen from v) -C(O)-O-R3, preferably substituted by a group iii) -C(O)-O-R3; R2 is more preferably a saturated hydrocarbon group, linear in C1-C4 or branched in C3-C4 substituted by a group iii) -C(O)-OR3; and

[0149] R3 denotes a radical chosen from

[0150] a) a hydrogen atom, and

[0151] b) a linear saturated CrC4 or C3-C4 branched alkyl group such as methyl or ethyl.

[0152] According to another preferred embodiment, the compounds of formula (I) and the tautomer (!') are chosen from the compounds of formula (II) below and also their tautomers of formula (II') below, their salts, their solvates and their optical isomers, and their racemates, alone or in mixture:

[0153] [Chem.7] on

[0154] In formulas (II) and (II'), Ri and R3 have the same meaning as Ri and R3 in the compounds of formula (I) and (I'), and X denotes an alkylene radical -(CH2)n-, n being an integer from 1 to 10 inclusive, preferably from 1 to 6, more preferably from 1 to 4, such that 1, preferably R3 represents a hydrogen atom.

[0155] Among the compounds of formula (I), the following compounds are preferably used, as well as their tautomer or their salts, their optical isomers, their racemates, and / or their solvates such as their hydrates, alone or in mixture:

[0156] [Tables2] No. Structure Chemical Name CAS No. 1 PHHH N-ethyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-75-5 2 \ ZX N-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-74-4 3 1 N-octyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-77-7 4 N-benzyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-79-9 H 1 ü 5 .—, «—4 M / %....... / \\ N-phényl-2-thioxo-1,2-d ihydropyridine-3-carboxamide 104857-16-1 6 o 4 'xrr"" M * H N-cyclohexyl-2-thioxo-1 ,2-dihydropyridine-3-carboxamide 91859-78-8 7 N- [2- (4-méthoxyphény 1 )éthyl]- 2-thioxo-1,2-dihydropyr idine- 3-carboxamide 923682-88-6 8 f fl T 4*K / 4 .,-x N-(2-méthylpropyl)-2-thioxo-1,2-dihydropyr idine-3-carboxamide 1100027-79- 9 9 f" V-^Xç.-'* xx.-‘' : j j H. N-pentyl-2-thioxo-1,2-di hydropyridine-3-carboxamide 330667-57-7 10 N-nonyl-2-thioxo-1,2-di hydropyridine-3-carboxamide 1031149-44- 6 ri ï 7 ' ' 11 / 7 / o—7 " """""\ \ 7 / \____( / / / \ / / \_ / N-(2-hydroxyéthyl)-2-thioxo-1,2-dihydropyr idine-3-carboxamide 12 0 / "5S. / N / 'XH'-r x r h • i < ..-i-s r. 5 N,N-diéthyl 2-mercapto nicotinamide 13 Vs x" Xy'"' Xj--,X !s Xx 1 "-'■■qm 1" \h N-éthyl-N-(2-hydroxyét hyl)-2-thioxo-1,2-dihydr opyridine-3-carboxamide 14 S!y J^x -^x >-4< >;SH N-(2,3-dihydroxypropyl )-2-thioxo-1,2-dihydrop yridine-3-carboxamide 15 N-( 1,3-dihydroxypropan -2-yl)-2-thioxo-1,2-dihy dropyridine-3-carboxamide 0 X z\ JK. .,ûh « 16 i -'■" S^XV*X 'hX' t X " 4 ''M'' XH / N-[(2-thioxo-1,2-dihydropyridin-3-yl)carb°nyl]ethyl laninate 17 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl phenyl laninate 18 X )r~\ : / ) / / / ' x\ / \ S .g-^ / '0 N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate 19 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate 20 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl] opyridin-3-yl)carbonyl]glycine 9 p.m....... / ____Z ; % N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl) carbonyl]glycine 22! H 11 ■SN,N-bis(2-hydroxyethyl)-2-thioxo-1,2-dihydrop yridine-3-carboxamide 23 J N-(3-methoxypropyl)-2-thioxo-1,2-dihydropyr idine-3-carboxamide 24 N-butyl-2-thioxo-1,2-dih ydropyridine-3-carboxamide Among these compounds, the following are particularly preferred:

[0157]

[0158] [Tables 3] No. Structure Chemical Name CAS No. 1 X t / hh H $ N-ethyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-75-5 2 / y >.\ x N-methyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-74-4 4 N-benzyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-79-9 6 :.X'X ...■■••■■■ ;; H N-cyclohexyl-2-thioxo-1,2-dihydropyridine-3-carboxamide 91859-78-8 7 .Ayx N-[2-(4-methoxyphenyl)ethyl] -2-thioxo-1,2-dihy dropyridine-3-carboxamide 923682-88-6 9 .-*' ?X N-pentyl-2-thioxo-1,2-di hydropyridine-3-carboxamide 330667-57-7 11 ,x' 1 0 )-2-thioxo-1,2-dihydrop yridine-3-carboxamide 15 § 1 ..CH x. -'^ % s< N-(1,3-dihydroxypropan -2-yl)-2-thioxo-1,2-dihy dropyridine-3-carboxamide 16 H ? opyridin-3-yl)carbonyl]alaninate ethyl 17 N-[(2-thioxo-l,2-dihydr pyridin-3-yl)carbonyl]phenylalanine ethyl x 18 L ZX- x, x. * 1 N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate 19 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate 20 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycine 21 GA .--x G n 'x <r" x"' Q CH; GW H N-méthyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycine More preferably, among these compounds, the following compounds are more

[0159]

[0160] particularly preferred: [Tables4] No. Structure Chemical Name CAS No. 1 HH N-ethyl-2-thioxo-1,2-dihydropyridine-3-carbamide 91859-75-5 9 < H ,-"X ..-"-x xS^ N-pentyl-2-thioxo-1,2-dihydropyridine-3-carbamide 330667-57-7 16 XK 'YS'" Ç\ N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl laninate 18 ^xx.. ,.* ^•î N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl glycinate 19 / m \ " \ s ' / \___ / N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]g lycinate ethyl 20 "V '■fi'* '-Î xx -0H rr V N-[(2-thioxo-l,2-dihydr pyridin-3-yl)carbonyl]g lycine

[0161] Even more preferentially, among these compounds, the following compounds are more particularly preferred:

[0162] [Tables5] No. Structure Chemical Name CAS No. 18 \ ,z ) %--------- / o Ethyl N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycinate 19 G il -v Q CH- / Il X " l1 H Ethyl N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycinate 20 N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycine 21 N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycine

[0163] In a most preferred embodiment, the compound according to the present invention is as follows:

[0165] All the above compounds can be obtained by a chemical process known to those skilled in the art, from commercially available reagents.

[0166] The (a) first compound can be prepared in accordance with the process described, for example, in EP-A-3390363 or WO 2017 / 102349.

[0167] The (a) first compound may be an active ingredient or an active compound in cosmetic or dermatological products. The term "active ingredient" or "active compound" used herein refers to an ingredient or compound that has an active cosmetic or dermatological property, such as antioxidant, bleaching, UV-filtering, and antibacterial effects. The (a) first compound used in the present invention may act as a depigmenting, bleaching, or bleaching agent, and thus the composition according to the present invention may be used as a bleaching product or as a cosmetic composition for bleaching keratinous material.

[0168] The (a) first compound can be used as an agent for depigmenting, bleaching or whitening skin, body hair, eyelashes or hair, and also lips and / or nails, and preferably skin, in particular for removing pigmentation spots or age spots, and / or as an anti-tanning agent.

[0169] As (a) the first compound, a commercially available product may be used. An example of (a) the first compound is Mexoryl SED sold by Noveal.

[0170] The quantity of the (a) first compound(s) in the composition according to the present invention may be 0.001% by weight or more, preferably 0.005% by weight or plus, and more preferably 0.01% by weight or more, relative to the total weight of the composition.

[0171] On the other hand, the quantity of the (a) first compound(s) in the composition according to the present invention may be 10% by weight or less, preferably 5% by weight or less, and more preferably 3% by weight or less, relative to the total weight of the composition.

[0172] Thus, the quantity of the (a) first compound(s) in the composition according to the present invention can range from 0.001% to 10% by weight, preferably from 0.005% to 5% by weight, and more preferably from 0.01% to 3% by weight, relative to the total weight of the composition.

[0173] (Second compound)

[0174] The composition according to the present invention comprises (b) at least one second compound selected from ergothioneine and its derivatives. Two or more second compounds may be used in combination. Thus, a single type of second compound or a combination of different types of second compounds may be used.

[0175] Ergothioneine and its derivatives may correspond to ergothioneine, as well as to their salts, esters and amides.

[0176] Ergothioneine has the following chemical structure.

[0177] [Chem.8]

[0178] Ergothioneine can act as an antioxidant or as an active oxygen scavenger. Examples of active oxygen include singlet oxygen, the superoxide ion (superoxide radical anion), the peroxide ion (hydrogen peroxide), and the hydroxyl radical.

[0179] Ergothioneine derivatives may correspond to compounds of the following formula (II):

[0180] (II)

[0181] in which:

[0182] - X represents a group -O-R', -OM or -NR'R";

[0183] - R, R' and R" represent, simultaneously or independently of each other, a hydrogen atom, an alkyl group, an alkenyl or acyl group in Ci-Ci8, and

[0184] - M represents a cation such as a metallic cation.

[0185] The expression "an alkyl, alkenyl or acyl group in C1 to C[8]" means a linear or branched alkyl, alkenyl or acyl group containing from 1 to 18 carbon atoms, optionally substituted by at least one substituent selected from the hydroxyl group (possibly itself esterified), halogen atoms, the carboxylic group and its derivatives and the amine group and its derivatives, and optionally containing in the chain at least one heteroatom such as O and S.

[0186] Preferably, R, R' and R" of chemical formula (II) above designate, simultaneously or independently of each other, a hydrogen atom or an ethyl, acetyl or acyl group, and preferably R designates a hydrogen atom or an ethyl, acetyl or acyl group, and X designates NH2.

[0187] More preferably, (b) the second compound is ergothioneine, and in particular L-(+)-ergothioneine, L-(-)-ergothioneine, D-(+)-ergothioneine or D-(-)-ergothioneine. The most preferred compound according to the invention is L-(+)-ergothioneine.

[0188] As (b) the second compound, a commercially available product may be used. An example of (b) the second compound is Bioyouth™ EGT Pure Ultrapure Ergothioneine sold by Bloomage Biotech.

[0189] The quantity of the (b) second compound(s) in the composition according to the present invention may be 0.001% by weight or more, preferably 0.005% by weight or more, and more preferably 0.01% by weight or more, relative to the total weight of the composition.

[0190] On the other hand, the quantity of the (b) second compound(s) in the composition according to the present invention may be 15% by weight or less, preferably 10% by weight or less, and more preferably 5% by weight or less, relative to the total weight of the composition.

[0191] The quantity of the (b) second compound(s) in the composition according to the present invention can range from 0.001% to 15% by weight, preferably from 0.005% to 10% by weight, more preferably from 0.01% to 5% by weight, relative to the total weight of the composition.

[0192] The weight ratio between the quantity of (a) first compound(s) and the quantity of (b) second compound(s) in the composition according to the present invention may be 0.1 or more, preferably 0.2 or more, and more preferably 0.3 or more.

[0193] On the other hand, the weight ratio between the quantity of the (a) first compound(s) and the quantity of the (b) second compound(s) in the composition according to the present invention may be 3 or less, preferably 2 or less, and more preferably 1 or less.

[0194] Thus, the weight ratio between the quantity of the (a) first compound(s) and the quantity of the (b) second compound(s) in the composition according to the present invention can go from 0.1 to 3, preferably from 0.2 to 2, and more preferably from 0.3 to 1. (Water)

[0195] The composition according to the present invention may include (c) water.

[0196] The quantity of (c) water in the composition according to the present invention may be 30% by weight or more, preferably 35% by weight or more, and more preferably 40% by weight or more, relative to the total weight of the composition.

[0197] On the other hand, the quantity of (c) water in the composition according to the present invention may be 99% by weight or less, preferably 95% by weight or less, and more preferably 90% by weight or less, relative to the total weight of the composition.

[0198] Thus, the quantity (c) of water in the composition according to the present invention can be from 30% to 99% by weight, preferably from 35% to 95% by weight, and more preferably from 40% to 90% by weight, relative to the total weight of the composition. (Fat)

[0199] The composition according to the present invention may comprise (d) at least one fat. If two or more fats are used, they may be identical or different.

[0200] The term "fat" here means an organic compound which is substantially insoluble in water at ordinary temperature (25 °C) and atmospheric pressure (760 mmHg or 101325 Pa) (with a solubility of less than 5% by weight, preferably less than 3% by weight, more preferably less than 1% by weight, and even more preferably less than 0.1% by weight).

[0201] On the other hand, (d) fat may be soluble in organic solvents under the same conditions of temperature and pressure, for example chloroform, ethanol, benzene or decamethylcyclopentasiloxane.

[0202] The (d) fat may contain, in its structure, a sequence of at least two siloxane groups or at least one hydrocarbon-based chain containing at least 6 carbon atoms. For the purposes of the present invention, it should be noted that the (d) fat does not comprise C2-C3 oxyalkylene motifs or glycerol motifs.

[0203] The (d) fat may be in the form of a liquid or a solid. Here, "liquid" and "solid" mean that the (d) fat is in the form of a liquid or a (non-solid) paste and a solid, respectively, at room temperature under atmospheric pressure. The term "solid" here refers to a substance that is not fluid under its own weight, unlike a liquid.

[0204] It is preferable that (d) fat be in the form of a liquid or a paste, preferably in the form of a liquid, at room temperature and under atmospheric pressure. Here, (d) fat which is in the form of a liquid at room temperature under atmospheric pressure may be called "oil".

[0205] The (d) fat may be volatile or non-volatile.

[0206] The (d) fat may be selected from the group consisting of oils and butters of animal or vegetable origin, aliphatic hydrocarbons, synthetic glycerides, silicone oils, fatty esters (other than oils and butters of animal or vegetable origin), fatty alcohols, fatty acids, and mixtures thereof.

[0207] Examples of oils of animal origin include, for example, squalene, perhydrosqualene and squalane.

[0208] Examples of oils of vegetable origin include, for example, linseed oil, camellia oil, macadamia nut oil, sunflower oil, apricot oil, soybean oil, arara oil, hazelnut oil, corn oil, mink oil, olive oil, avocado oil, sasanqua oil, castor oil, safflower oil, jojoba oil, sunflower oil, almond oil, grapeseed oil, sesame oil, soybean oil and peanut oil.

[0209] Examples of butters of vegetable origin include, for example, shea butter or Butyrospermum parkii butter, Nilotica shea butter, galam butter, Borneo butter or fat or tengkawang tallow (Shorea stenoptera), shorea butter, illipe butter, madhuca butter or Madhuca longifolia butter (Bassia), mowrah butter (Madhuca latifolia), katiau butter (Madhuca mottleyana), phulwara butter (M. butyracea), mango butter (Mangifera indica), murumuru butter (Astrocaryum murumuru), kokum butter (Garcinia indica), ucuuba butter (Virola sebifera), tucuma butter, painya (kpangnan) butter (Pentadesma butyracea), coffee butter (Coffea arabica), apricot butter (Prunus armeniaca), macadamia butter (Macadamia ternifolia), grape seed butter (Vitis vinifera), avocado butter (Persea gratissima), butter olive (Olea europaea), sweet almond (Prunus amygdalus dulcis), cocoa (Theobroma cacao) butter and sunflower butter.

[0210] In one embodiment of the present invention, it is preferable to use shea butter.

[0211] Examples of aliphatic hydrocarbons include, for example, linear or branched hydrocarbons such as mineral oil (e.g., liquid paraffin), paraffin, Vaseline or petrolatum, naphthalenes, and the like; hydrogenated polyisobutene, isoeicosane, polydecenes, hydrogenated polyisobutenes such as Parleam, and a decene / butene copolymer; and mixtures thereof.

[0212] Other examples of aliphatic hydrocarbons include lower C6-Ci6, C9-Ci2, and C15-C19 alkanes, whether linear, branched, or possibly cyclic. Examples that may be cited include hexane, undecane, dodecane, tridecane, and isoparaffins such as isohexadecane and isodecane.

[0213] Examples of synthetic glycerides include, for example, caprylic / capric acid triglycerides, for example those sold by Stéarineries Dubois or those sold under the names Miglyol® 810, 812 and 818 by Dynamit Nobel.

[0214] Examples of silicone oils include, for example, linear organopolysiloxanes such as dimethylpolysiloxanes, methylphenylpolysiloxanes, methylhydrogenopolysiloxanes and the like; cyclic organopolysiloxanes such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and the like; and mixtures thereof.

[0215] By way of examples of fatty esters (esters of a fatty acid and / or a fatty alcohol) that are different from the oils and butters of animal or vegetable origin, as well as the synthetic glycerides mentioned above, one may cite in particular the esters of mono- or polyaliphatic acids, saturated or unsaturated, linear or branched in C1-C26 and of aliphatic mono- or polyalcohols, saturated or unsaturated, linear or branched in Ci-C26, the total number of carbons of the esters being greater than or equal to 10.

[0216] Among the monoesters, the following may be mentioned: dihydroabietyl behenate; octyldodecyl behenate; isocetyl behenate; cetyl lactate; C12-C15 alkyl lactate; isostearyl lactate; lauryl lactate; linoleyl lactate; oleyl lactate; (iso)stearyl octanoate; isocetyl octanoate; octyl octanoate; cetyl octanoate; decyl oleate; isocetyl isostearate; isocetyl laurate; isocetyl stearate; isocetyl octanoate; isocetyl oleate; isononyl isononanoate; isostearyl palmitate; methylacetyl ricinoleate; myristyle stearate; octyl isononanoate; 2-ethylhexyl isononate; octyl palmitate; octyl pelargonate; octyl stearate; octyldodecyl erucate; oleyl erucate;ethyl and isopropyl palmitates, 2-ethylhexyl palmitate, 2-octyldecyl palmitate, alkyl myristates such as isopropyl, butyl, cetyl, 2-octyldodecyl, myristyle or stearyl myristate, hexyl stearate, butyl stearate, isobutyl stearate; dioctyl malate, hexyl laurate, and 2-hexyldecyl laurate.

[0217] Still within the context of this variant, C4-C22 dicarboxylic or tricarboxylic acid esters and C1-C22 alcohol esters and C2-C26 mono-, di- or tricarboxylic acid esters and di-, tri-, tetra- or pentahydroxy alcohol esters may also be used.

[0218] The following may be mentioned in particular: diethyl sebacate; diisopropyl sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl adipate; diisostearyl adipate; dioctyl maleate; glyceryl undecylenate; octyldodecyl stearoyl stearate; pentaerythrityl monoricinoleate; pentaerythrityl tetraisononanoate; pentaerythrityl tetrapelargonate; pentaerythrityl tetraisostearate; pentaerythrityl tetraoctanoate; propylene glycol dicaprylate; propylene glycol dicaprate; tridecyl erucate; triisopropyl citrate; triisostearyl citrate; glyceryl trilactate; glyceryl trioctanoate; trioctyldodecyl citrate; trioleyl citrate, propylene glycol dioctanoate; neopentyl glycol diheptanoate; diethylene glycol diisononanoate; and polyethylene glycol distearates.

[0219] Among the esters mentioned above, it may be preferable to use ethyl, isopropyl, myristyle, cetyl or stearyl palmitate, 2-ethylhexyl palmitate, 2-octyldecyl palmitate, alkyl myristates such as isopropyl, butyl, cetyl or 2-octyldodecyl myristate, hexyl stearate, butyl stearate or isobutyl stearate; dioctyl malate, hexyl laurate, 2-hexyldecyl laurate, isononyl isononanoate or cetyl octanoate.

[0220] The composition according to the present invention may also include, as fatty acid esters, sugar esters and C6 to C30 fatty acid diesters, and preferably C12 to C22. It is recalled that the term "sugar" refers to oxygen-bearing hydrocarbon compounds containing several alcohol functional groups, with or without aldehyde or ketone functional groups, and containing at least four carbon atoms. These sugars may be monosaccharides, oligosaccharides, or polysaccharides.

[0221] Examples of suitable sugars that may be cited include sucrose, glucose, galactose, ribose, fructose, maltose, mannose, arabinose, xylose, lactose and their derivatives, including alkyl derivatives, such as methyl derivatives, for example methylglucose.

[0222] Sugar esters of fatty acids may be selected in particular from the group comprising the esters or mixtures of esters of sugars described above and of linear or branched fatty acids, saturated or unsaturated in C6-C30> and preferably in C12-C22. If they are unsaturated, these compounds may comprise one to three conjugated or non-conjugated carbon-carbon double bonds.

[0223] The esters according to this variant can also be chosen from mono-, di-, tri-, tetraesters and polyesters, and their mixtures.

[0224] These esters may be selected, for example, from oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates and arachidonates, or mixtures thereof such as, in particular, mixed esters of oleopalmitate, oleostearate and palmitostearate.

[0225] It may be more preferable to use monoesters and diesters, and in particular mono- or dioleates, stearates, behenates, oleopalmitates, linoleates, linolenates and oleostearates of sucrose, glucose or methylglucose.

[0226] An example that can be cited is the product sold under the name Glucate® DO by the company Amerchol, which is a methylglucose dioleate.

[0227] Examples of esters or mixtures of sugar and fatty acid esters that may also be cited include:

[0228] - the products sold under the names Crodesta F160, F140, Fl 10, F90, F70 and SL40 by the company Crodesta, designating respectively sucrose palmitostearates formed from 73% monoester and 27% diester and triester, from 61% monoester and 39% diester, triester and tetraester, from 52% monoester and 48% diester, triester and tetraester, from 45% monoester and 55% diester, triester and tetraester, from 39% monoester and 61% diester, triester and tetraester, and sucrose monolaurate;

[0229] - products sold under the name Ryoto Sugar Esters, for example reference B370 and corresponding to sucrose behenate formed from 20% monoester and 80% di-, tri-, polyester;

[0230] - sucrose monodipalmitate / stearate sold by Goldschmidt under the name Tegosoft® PSE.

[0231] The (d) fat may be at least one fatty acid, and two or more fatty acids may be used.

[0232] The fatty acids must be in acidic form (i.e., unsalted, to avoid soaps) and may be saturated or unsaturated and contain from 6 to 30 carbon atoms, and in particular from 9 to 30 carbon atoms, which are optionally substituted, in particular by one or more hydroxyl groups (in particular 1 to 4). If unsaturated, these compounds may comprise one to three conjugated or non-conjugated carbon-carbon double bonds. They are particularly chosen from myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, linoleic acid, linolenic acid, and isostearic acid.

[0233] The (d) fat may be at least one fatty alcohol, and two or more fatty alcohols may be used.

[0234] The term "fatty alcohol" herein means any saturated or unsaturated, linear or branched C8-C30 fatty alcohol that is optionally substituted, in particular with one or more hydroxyl groups (in particular 1 to 4). If unsaturated, these compounds may comprise one to three conjugated or non-conjugated carbon-carbon double bonds.

[0235] Among C8-C30 fatty alcohols, C12-C22 fatty alcohols, for example, may be used. Examples include lauryl alcohol, cetyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, behenyl alcohol, linoleyl alcohol, undecylenyl alcohol, palmitoleyl alcohol, linolenylic alcohol, myristyl alcohol, arachidonyl alcohol, and erucyl alcohol, and mixtures thereof. In one embodiment, cetyl alcohol, stearyl alcohol, or a mixture thereof (for example, cetearyl alcohol), as well as myristyl alcohol, may be used as a solid fat. In another embodiment, isostearyl alcohol can be used as a liquid fat.

[0236] In one embodiment of the present invention, the (d) fat may be a wax. Here, "wax" means a fat that is substantially in the form of a solid at room temperature (25 °C) under atmospheric pressure (760 mmHg or 101,325 Pa), and generally has a melting point of 35 °C or higher. As waxy fats, waxes commonly used in cosmetics may be used alone or in combination.

[0237] For example, the wax may be selected from carnauba wax, microcrystalline waxes, ozokerites, hydrogenated jojoba oil, polyethylene waxes such as the wax sold under the name "Performalene 400 Polyethylene" by New Phase Technologies, silicone waxes, for example poly(C24-C28)alkylmethyldimethylsilane, such as the product sold under the name "Abil Wax 9810" by Goldschmidt, palm butter, C2O-C4O alkyl stearate sold under the name "Kester Wax K82H" by Koster Keunen, stearyl benzoate, shellac wax, and mixtures thereof. For example, a wax selected from carnauba wax, candelilla wax, ozokerites, hydrogenated jojoba oil, and polyethylene waxes may be used. In at least one embodiment, the wax is preferably selected from candelilla wax and ozokerite, and mixtures thereof.

[0238] It is preferable that the (d) fat be chosen from aliphatic hydrocarbons, vegetable oils, vegetable butters, and mixtures thereof, and more preferably from aliphatic hydrocarbons, vegetable butters, and mixtures thereof, and even more preferably from alkanes, shea butter, and mixtures thereof.

[0239] The quantity of the (d) fat(s) in the composition according to the present invention may be 0.1% by weight or more, preferably 0.5% by weight or more, and more preferably 1% by weight or more, relative to the total weight of the composition.

[0240] On the other hand, the quantity of the (d) fat(s) in the composition according to the present invention may be 15% by weight or less, preferably 10% by weight or less, and more preferably 5% by weight or less, relative to the total weight of the composition.

[0241] Thus, the quantity of the (d) fat(s) in the composition according to the present invention can be from 0.1% to 15% by weight, preferably from 0.5% to 10% by weight, and more preferably from 1% to 5% by weight, relative to the total weight of the composition. (Surfactant)

[0242] The composition according to the present invention may comprise (e) at least one surfactant. If two or more surfactants are used, they may be identical or different.

[0243] The (e) surfactant may be selected from the group consisting of (e1) anionic surfactants, (e2) cationic surfactants, (e3) amphoteric surfactants, (e4) non-ionic surfactants, and mixtures thereof.

[0244] It is preferable that the (e) surfactant be chosen from among the (e4) non-ionic surfactants.

[0245] The quantity of the surfactant(s) in the composition according to the present invention may be 0.01% by weight or more, preferably 0.05% by weight or more, and more preferably 0.1% by weight or more, relative to the total weight of the composition.

[0246] On the other hand, the quantity of the surfactant(s) in the composition according to the present invention may be 10% by weight or less, preferably 5% by weight or less, and more preferably 1% by weight or less, relative to the total weight of the composition.

[0247] Thus, the quantity of the surfactant(s) in the composition according to the present invention can range from 0.01% to 10% by weight, preferably from 0.05% to 5% by weight, and more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

[0248] Anionic surfactant:

[0249] It may be preferable that the anionic surfactant be selected from the group consisting of (C6-C30)alkyl sulfates, (C6-C30)alkyl ether sulfates, (C6-C30)alkylamido ether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates; (C6-C30)alkylsulfonates, (C6-C30)alkylamide sulfonates, (C6-C30)alkylaryl sulfonates, α-olefin sulfonates, and paraffin sulfonates; (C6-C30)alkyl phosphates; (C6-C30)alkyl sulfosuccinates, (C6-C30)alkyl ether sulfosuccinates, (C6-C30)alkylamide sulfosuccinates; (C6-C30)alkyl sulfoacetates; (C6-C24)acyl sarcosinates; (C6-C24)acyl glutamates; (C6-C30)alkylpolyglycoside carboxylic ethers; (C6-C30)alkylpolyglycoside sulfosuccinates; (C6-C30)alkyl sulfosuccinamates; (C6-C24)acyl isethionates; N-(C6-C24)acyl taurates; C6-C30 fatty acid salts; coconut oil acid salts or hydrogenated coconut oil acid salts; (C8-C20)acyl lactylates; (C6-C30)alkyl-D-galactoside uronic acid salts;salts of (C6-C30)alkyl ether polyoxyalkylenated carboxylic acids; salts of (C6-C30)alkylaryl ether polyoxyalkylenated carboxylic acids and salts of (C6-C30)alkylamido ether polyoxyalkylenated carboxylic acids; and their corresponding acidic forms.

[0250] In at least one embodiment, the anionic surfactants are in the form of salts such as alkali metal salts, for example sodium; alkaline earth metal salts, for example magnesium; ammonium salts; amine salts; and amino alcohol salts. Depending on the conditions, they may also be in acidic form.

[0251] Cationic surfactant:

[0252] The (e2) cationic surfactant may be selected from the group consisting of primary, secondary or tertiary fatty amine salts optionally polyoxyalkylated, quaternary ammonium salts, and mixtures thereof.

[0253] According to one embodiment, the (e2) cationic surfactant that can be used in the composition according to the present invention is selected from behenyltrimethylammonium chloride, cetyltrimethylammonium chloride, quaternium-83, quaternium-87, quaternium-22, behenyllamidopropyl-2,3-dihydroxypropyldimethylammonium chloride, palmitylamidopropyltrim ethylammonium chloride and stearamidopropyldimethylamine.

[0254] Amphoteric surfactant:

[0255] Amphoteric surfactants (zwitterionic surfactants) may be, for example (non-limiting list), amine derivatives such as aliphatic secondary or tertiary amines, and optionally quaternized amine derivatives, in which the aliphatic radical is a linear or branched chain including 8 to 22 carbon atoms and containing at least one water-soluble anionic group (e.g., carboxylate, sulfonate, sulfate, phosphate or phosphonate).

[0256] The (e3) amphoteric surfactant may preferably be chosen from the group consisting of betaines and amidoaminecarboxylated derivatives.

[0257] In one embodiment, the (e3) amphoteric surfactant may be selected from betaine-type surfactants.

[0258] The amphoteric surfactant of the betaine type is preferably selected from the group consisting of alkylbetaines, alkylamidoalkylbetaines, sulfobetaines, phosphobetaines, and alkylamidoalkylsulfobetaines, in particular, (C8-C24)alkylbetaines, (C8-C24)alkylamido(Ci-C8)alkylbetaines, sulfobetaines, and (C8-C24)alkylamido(Ci-C8)alkylsulfobetaines. In one embodiment, the (e3) amphoteric surfactants of the betaine type are selected from (C8-C24)alkylbetaines, (C8-C24)alkylamido(Ci-C8)alkylsulfobetaines, sulfobetaines, and phosphobetaines.

[0259] Non-limiting examples that may be cited include compounds classified in the CTFA International Cosmetic Ingredient Dictionary & Handbook, 15th edition, 2014, under the names cocobetaine, laurylbetaine, cetylbetaine, coco / oleamidopropylbetaine, cocamidopropylbetaine, palmitamidopropylbetaine, stearamidopropylbetaine, cocamidoethylbetaine, cocamidopropylhydroxysultaine, oleamidopropylhydroxysultaine, cocohydroxysultaine, laurylhydroxysultaine and cocosultaine, alone or in mixtures.

[0260] The amphoteric surfactant of the betaine type is preferably an alkylbetaine and an alkylamidoalkylbetaine, in particular cocobetaine and cocamidopropylbetaine. (Non-ionic surfactant)

[0261] The (e4) nonionic surfactants may be selected from alkyl and polyalkyl esters of poly(ethylene oxide), alkyl and polyalkyl ethers of poly(ethylene oxide), oxyalkyl alcohols, optionally alkyl and polyalkyl polyoxyethylenated esters of sorbitan, optionally alkyl and polyalkyl polyoxyethylenated ethers of sorbitan, alkyl and polyalkyl glycosides or polyglycosides, in particular alkyl and polyalkyl glucosides or polyglucosides, alkyl and polyalkyl esters of sucrose, optionally alkyl and polyalkyl polyoxyethylenated esters of glycerol, and optionally alkyl and polyalkyl polyoxyethylenated ethers of glycerol, and mixtures thereof.

[0262] In one embodiment, the (e4) nonionic surfactant can be selected from fatty acid polyglyceryl esters.

[0263] The fatty acid polyglyceryl ester may have a polyglycerol fraction derived from 2 to 10 glycerols, preferably from 2 to 8 glycerols, and more preferably from 2 to 6 glycerols. In other words, the fatty acid polyglyceryl ester may comprise from 2 to 10 polyglyceryl units, preferably from 2 to 8 polyglyceryl units, and more preferably from 2 to 6 polyglyceryl units.

[0264] The fatty acid polyglyceryl ester may be selected from mono, di and tri esters of linear or branched fatty acids, saturated or unsaturated, preferably of saturated fatty acids, including from 4 to 32 carbon atoms, preferably from 8 to 26 carbon atoms, and more preferably from 10 to 20 carbon atoms, such as lauric acid, oleic acid, stearic acid, isostearic acid, capric acid, caprylic acid and myristic acid.

[0265] It is preferable that the (c4) nonionic surfactant be chosen from polyglyceryl monoesters of saturated or unsaturated fatty acid.

[0266] The fatty acid polyglyceryl ester may have an HLB (hydrophilic-lipophilic balance) value of 7.0 to 16.0, preferably 7.5 to 15.5, and more preferably 8.0 to 15.0. The term HLB (hydrophilic-lipophilic balance) is well known to those skilled in the art and reflects the ratio between the hydrophilic and lipophilic parts in the molecule. If two or more fatty acid polyglyceryl esters are used, the HLB value is determined by the weighted average of the HLB values ​​of all the fatty acid polyglyceryl esters.

[0267] The fatty acid polyglyceryl ester may be selected from the group consisting of PG-2 caprate (HLB: 9.5), PG-2 laurate (HLB: 8.5), PG-4 oleate (HLB: 8.8), PG-4 laurate (HLB: 10.4), PG-4 isostearate (HLB: 8.2), PG-5 laurate (HLB: 15.8), PG-6 isostearate (HLB: 10.8), PG-3 cocoate (HLB: 12.0), PG-3 caprate (HLB: 10.0), PG-4 caprylate (HLB: 14), PG-4 caprate (HLB: 14.0), PG-5 myristate (HLB: 15.4), PG-5 stearate (HLB: 15.0), PG-5 oleate (HLB: 14.9), PG-6 caprylate (HLB: 14.6), PG-6 caprate (HLB: 13.1), PG-6 laurate (HLB: 14.5), and mixtures thereof.

[0268] It may be preferable that the (e4) nonionic surfactant be chosen from fatty acid polyglyceryl esters, more preferably saturated fatty acid polyglyceryl esters, and even more preferably saturated fatty acid polyglyceryl monoesters such as PG-4 caprate. (pH)

[0269] The pH of the aqueous phase of the composition according to the present invention can be from 3 to 7, preferably from 4 to 6.5, and more preferably from 5 to 6.

[0270] The pH of the composition according to the present invention can be corrected by the addition of at least one alkaline agent and / or at least one acid.

[0271] The pH of the composition according to the present invention can also be corrected by adding at least one buffering agent.

[0272] Alkaline Agent:

[0273] The composition according to the present invention may comprise at least one alkali agent. Two or more alkali agents may be used in combination. Thus, a single type of alkali agent or a combination of different types of alkali agents may be used.

[0274] The alkali agent may be an inorganic alkali agent. Preferably, the inorganic alkali agent should be chosen from the group consisting of ammonia, alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal phosphates, and monohydrogen phosphates such as sodium phosphate or sodium monohydrogen phosphate.

[0275] Examples of inorganic alkali metal hydroxides include sodium hydroxide and potassium hydroxide. Examples of alkaline earth metal hydroxides include calcium hydroxide and magnesium hydroxide. Sodium hydroxide is preferable as an inorganic alkali metal.

[0276] The alkali agent may be an organic alkali agent. Preferably, the organic alkali agent should be chosen from the group consisting of monoamines and their derivatives; diamines and their derivatives; polyamines and their derivatives; basic amino acids and their derivatives; oligomers of basic amino acids and their derivatives; polymers of basic amino acids and their derivatives; urea and its derivatives; and guanidine and its derivatives.

[0277] Examples of organic alkali-aggregates include alkanolamines such as mono-, di- and tri-ethanolamine, and isopropanolamine; urea, guanidine and their derivatives; basic amino acids such as lysine, ornithine; and diamines such as those described in the structure below:

[0278] [Chem. 10] RI R3 NRN / x

[0279] in which

[0280] - R denotes an alkylene such as propylene optionally substituted by a hydroxyl or an alkyl radical in Ci-C4, and Rb R2, Ri and R4 independently denote a hydrogen atom, an alkyl radical or a hydroxyalkyl radical in CrC4, an example of which may be 1,3-propanediamine and its derivatives.

[0281] The alkali agent(s) may be used in an amount from 0.01% to 15% by weight, preferably from 0.02% to 10% by weight and more preferably from 0.03% to 5% by weight, relative to the total weight of the composition, depending on their solubility.

[0282] Acid:

[0283] The composition according to the present invention may comprise at least one acid. Two or more acids may be used in combination. Thus, a single type of acid or a combination of different types of acids may be used.

[0284] As an acid, any inorganic or organic acids, preferably inorganic, that are commonly used in cosmetic products may be used. A monovalent acid and / or a polyvalent acid may be used. A monovalent acid such as citric acid, lactic acid, sulfuric acid, phosphoric acid, and hydrochloric acid (HCl) may be used. Lactic acid may be preferred.

[0285] The acid or acids may be used in a total quantity of 0.01% to 15% by weight, preferably 0.02% to 10% by weight, more preferably 0.03% to 5% by weight, relative to the total weight of the composition, depending on their solubility. (Other optional additives)

[0286] The composition according to the present invention may also include any other optional additive(s) commonly used in the field of cosmetics, chosen, for example, from solvents, thickeners, fillers, UV filters, fatty acids, cosmetic active agents other than ingredient (a), preservatives, and mixtures thereof.

[0287] It is part of the ordinary operations for a person skilled in the art to adjust the nature and quantity of the above optional additives which may be present in the composition according to the present invention in such a way that the desired cosmetic properties are not affected by them.

[0288] By way of solvents, one or more cosmetically acceptable organic solvents may be mentioned, which may be alcohols: in particular monovalent alcohols such as ethyl alcohol, isopropyl alcohol, benzyl alcohol and phenylethyl alcohol; diols such as ethylene glycol, propylene glycol and butylene glycol; other polyols such as glycerol, sugar and sugar alcohols; and ethers such as monomethyl, monoethyl and monobutyl ethers of ethylene glycol, monomethyl, monoethyl and monobutyl ethers of propylene glycol, and monomethyl, monoethyl and monobutyl ethers of butylene glycol.

[0289] The organic solvent(s) may be present in a concentration of 0.01% to 30% by weight, preferably 0.05% to 20% by weight, and more preferably 0.1% to 10% by weight, relative to the total weight of the composition. (Preparation)

[0290] The composition according to the present invention can be prepared by mixing the essential and optional ingredients described above in a conventional manner.

[0291] For example, the composition according to the present invention can be prepared by a process comprising the steps of

[0292] mixture a. of at least one first compound explained above; and b. of at least one second compound explained above.

[0293] It is also possible to mix in any of the optional ingredients.

[0294] The mixing can be carried out at any temperature such as room temperature (e.g., 20-25 °C, preferably 25 °C), preferably at 30 °C or higher, preferably 40 °C or higher, and more preferably 50 °C or higher. It is preferable to further carry out the mixing with any of the optional ingredients described above, such as a pH corrector.

[0295] The form of the composition according to the present invention is not limited in particular, and may take various forms such as a W / O emulsion, an O / W emulsion, a gel, a solution, or the like. Preferably, the composition according to the present invention is in the form of an emulsion, preferably an O / W emulsion, and more preferably an O / W gel emulsion. [Cosmetic process]

[0296] The composition according to the present invention can be used as a cosmetic or dermatological composition, preferably as a cosmetic composition, and more preferably as a cosmetic composition for keratinous material. Examples of keratinous material include skin, scalp, hair, and mucous membranes such as lips and nails. It is even more preferable that the composition according to the present invention is used as a cosmetic composition for the skin.

[0297] The composition according to the present invention can be used as a depigmenting, bleaching, or whitening product for keratinous material such as skin. In particular, the composition according to the present invention can be used as a whitening product.

[0298] The composition according to the present invention may preferably be intended for application on a keratinous material such as skin, scalp and / or lips, preferably skin.

[0299] Thus, the composition according to the present invention can be used for a cosmetic process on a keratinous material, preferably skin. In one embodiment, the present invention relates to a cosmetic process, preferably a whitening process, for a keratinous material, preferably skin, comprising the step of applying the composition according to the present invention to the keratinous material.

[0300] The composition according to the present invention can be used as a topical cosmetic composition in the form of a lotion, a milky lotion, a cream, a gel, a paste, a serum, a foam or a spray. [Use]

[0301] The present invention also relates to the use of (b) at least one second compound selected from ergothioneine and its derivatives in a composition comprising (a) at least one first compound selected from the compounds of formula (I) below, the tautomers of formula (!') below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and mixtures thereof:

[0302] [Chem. 11]

[0303] in which

[0304] - Ri designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in the form of Ci-Cio or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, and ii. -S-R3,

[0305] and

[0306] - R2 denotes a radical chosen from a. a hydrogen atom, b. a saturated hydrocarbon group, linear in C1-C12 or branched in C3-C12 or cyclic in C3-C8, optionally substituted by one or more groups, which may be identical or different, chosen from i. -O-R3, ii. -S-R3, iii. -C(O)-O-R3, and iv. an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in CrC8, and a. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals

[0307] in which

[0308] - R3 designates a radical chosen from a. a hydrogen atom, and b. a linear saturated alkyl group in C1-C10 or branched in C3-Ci0

[0309] in order to stabilize the (a) first compound(s).

[0310] The term "stabilize" has the same meaning as strengthening stability.

[0311] Use according to the present invention may increase the stability of (a) first compound in the composition comprising it.

[0312] Therefore, the use according to the present invention can allow a composition comprising the (a) first compound to be stored for a long period of time, and in particular even under high temperature conditions.

[0313] The above explanations concerning the (a) first compound and the (b) second compound for the compositions according to the present invention can also be applied to those used in the use according to the present invention.

[0314] The composition in use according to the present invention may include any of the optional ingredients as explained above for compositions according to the present invention. EXAMPLES

[0315] The present invention will be described in more detail by means of examples. However, these examples shall not be construed as limiting the scope of the present invention. Example 1 and Comparative Examples 1-6 [Preparation]

[0316] Each of the compositions according to Example 1 and Comparative Examples 1-6 was prepared by mixing the ingredients indicated in Table 1. The numerical values ​​for the quantities of the ingredients are all based on the "% by weight" as active substances.

[0317] [Tables?] Ingredients Ex. 1 Ex. C omp. 1 Ex. C omp. 2 Ex. C omp. 3 Ex. C omp. 4 Ex. C omp. 5 Ex. C omp. 6 Water qspl 00 qspl 00 qspl 00 qspl 00 qspl 00 qspl 00 qspl 00 Glycerin 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Oleic acid 5.0 5.0 5.0 5.0 5.0 5.0 5.0 Butylene glycol 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 C15-19 Alkane 3.0 3.0 3.0 3.0 3.0 3.0 3.0 Butyrospermum Parkii Butter (Shea) 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Homosalate 10.0 10.0 10.0 10.0 10.0 10.0 10.0 Polyglyceryl-4 Caprate 0.9 0.9 0.9 0.9 0.9 0.9 0.9 Perlite 4.0 4.0 4.0 4.0 4.0 4.0 4.0 Phenoxyethanol 0.6 0.6 0.6 0.6 0.6 0.6 0.6 Ammonium Acryloyldimethyl Yltaurate / VP Copolymer 0.4 0.4 0.4 0.4 0.4 0.4 0.4 2-Mercaptonicotinoyl Glycine 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Ergothioneine 1.0 - - - - - - Serine - - 1.0 - - - - Aspartic Acid - - - 1.0 - - - Carnosine - - - - 1.0 - - Histidine - - - - - 1.0 - Taurine - - - - - - 1.0

[0318] 2-Mercaptonicotinoyl Glycine: N-[(2-thioxo-l,2-dihydropyridin-3-yl)carbonyl]glycine (Compound 20) [Evaluations] (Remaining level of thiopyridinone compound)

[0319] 1.0 g of each of the compositions according to Example 1 and the Comparative Examples Parts 1 to 6 were mixed with 50 mL of water to prepare an aqueous solution of the composition. Methanol was added to the aqueous solution of the composition and the mixture was subjected to sonication followed by stirring for approximately 1.5 hours. The resulting solution was filtered.

[0320] A portion of the filtered solution was subjected to HPLC-UV analysis to determine the amount of the compound thiopyridinone (2-Mercaptonicotinoyl Glycine) at the next time step (1).

[0321] Another portion of the filtered solution was placed in a sealed container protecting from light at 55 °C for 2 weeks, and subjected to HPLC-UV analysis to determine the amount of the thiopyridinone compound (2-Mercaptonicotinoyl Glycine) at the next time point (2).

[0322] Another portion of the filtered solution was placed in a sealed container protecting from light at 45 °C for 2 months, and subjected to HPLC-UV analysis to determine the amount of the thiopyridinone compound (2-Mercaptonicotinoyl Glycine) at the next time point (3).

[0323] Instant (1) Just after preparation (T0)

[0324] Instant (2) 2 weeks after preparation (T2W)

[0325] Instant (3) 2 months after preparation (T2M)

[0326] The details of the HPLC-UV assay are as follows.

[0327] Apparatus / Reagents

[0328] [Tables8] High-performance liquid chromatography (UPLC) system. RP18 HPLC column, 1.7 µm, 2.1 mm x 100 mm. Eluent A: 0.1% phosphoric acid in water. Eluent B: Methanol.

[0329] HPLC Conditions

[0330] [Tables9] UV detector 296 nm, column temperature 30 °C Flow rate 0.4 mL / min Injection volume 1 pL Mobile phase Gradient mode A: Phosphoric acid 0.1% in water B: Methanol

[0331] The remaining level of thiopyridinone compound was determined by the following equation:

[0332] Remaining percentage of thiopyridinone compound T2W (%) =

[0333] Quantity of thiopyridinone compound at time (2) / Quantity of thiopyridinone compound at time (1)

[0334] Remaining percentage of thiopyridinone compound T2M (%) =

[0335] Quantity of thiopyridinone compound at time (3) / Quantity of thiopyridinone compound at time (1)

[0336] The results are presented in the rows "Remaining rate of thiopyridinone compound T2W (%)" and "Remaining rate of thiopyridinone compound T2M (%)" in Table 2 below.

[0337] [TableauxlO] Ex. 1 Ex. Comp. 1 Ex. Comp. 2 Ex. Comp. 3 Ex. Comp. 4 Ex. Comp. 5 Ex. Comp. 6 T2W Thiopyridinone Compound Remaining Percentage (%) 90.9 90.3 85.3 89.3 83.2 87.3 84.0 T2M Thiopyridinone Compound Remaining Percentage (%) 85.2 79.9 64.4 74.2 56.3 72.7 60.5 (Results)

[0338] The composition according to Example 1, which included ergothioneine, was stable, even at high temperature, for a long period, so that a larger quantity of the thiopyridinone compound remained than in the compositions according to Comparative Examples 1 to 6, which did not include ergothioneine or included an amino acid (serine, aspartic acid, or histidine), an amino acid peptide (carnosine), or an amino acid analogue (taurine), which is different from ergothioneine.

Claims

Demands

1. Composition, preferably a cosmetic composition, and more preferably a cosmetic composition for the skin, comprising (a) at least one compound selected from the compounds of formula (I) below, the tautomers of formula (!') below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures: [Chem. 12] O 0) in which - Ri designates a radical chosen from a) a hydrogen atom, and b) a linear saturated alkyl group in the form of Ci-CiO or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i) -O-R3, and ii) -S-R3, and - R2 denotes a radical chosen from a) a hydrogen atom, b) a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8 optionally substituted by one or more groups, which may be the same or different, selected from i) -O-R3, ü) -S-R3, iii) -C(O)-O-R3, and (iv) an aryl group in the C5-C12 position, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in the C1-C8 position, and (c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in Ci-c8, in which -R3 denotes a radical selected from (a) a hydrogen atom, and (b) a linear saturated alkyl group in Ci-Cio or branched in C3-Ci0; and (b) at least one second compound selected from ergothioneine and its derivatives.

2. Composition according to claim 1, wherein: - Ri of formula (I) and (!') represents a radical selected from a) a hydrogen atom, and b) a linear saturated alkyl group in Ci-C6 or branched in C3-C6 optionally substituted by one or more groups, which may be identical or different, selected from i) -O-R3, and ii) -S-R3, preferably optionally substituted by one or more i groups);- R2 of formula (I) and (!') represents a radical chosen from a) a hydrogen atom, and b) a linear saturated hydrocarbon group in Ci-Cio or branched in C3-Cio or cyclic in C3-C8 such as in C5-C6, optionally substituted by one or more groups, which may be identical or different, chosen from i) -O-R3, ii) -S-R3, iii) -C(O)-O-R3, and iv) a phenyl group optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in Ci-C4 such as methoxy, preferably substituted by one or more groups chosen from i) and iii), preferably iii) such as carboxy; and - R3 of formula (I) and (!') represents a radical chosen from a) a hydrogen atom, and b) a linear saturated alkyl group in Ci-C6 or branched in C3-C6,;

3. Preferably, the compounds of formula (I) and the tautomer (!'), their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures, have the following meanings: - Ri of formula (I) and (!') represents a radical chosen from: a) a hydrogen atom, and b) a linear saturated alkyl group in C1-C4 or branched in C3-C4 optionally substituted by one or more groups, which may be identical or different, chosen from i) -OR3jplus preferably unsubstituted; - R2 of formula (I) and (!') represents a radical chosen from a) a hydrogen atom, and (b) a linear saturated hydrocarbon group in C1-C10 or branched in C3-C10 or cyclic in C3-C8 such as in C5-C6, optionally substituted by one or more groups, which may be the same or different, selected from i) -O-R3, iii) -C(O)-O-R3, and (iv) an aryl group in the C5-C12 position, optionally substituted by one or more hydroxyl groups and / or by one or more Ci-C4 alkoxy radicals; and - R3 of formula (I) and (!') represents a radical chosen from: a) a hydrogen atom; b) a linear saturated CrC4 or C3-C4 branched alkyl group such as methyl or ethyl. Composition according to any one of claims 1 and 2, wherein: (a) the first compound is chosen from compounds 1 to 24 below, their tautomers, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and their mixtures, in particular compounds 1, 2, 4, 6, 7, 9, 11, 12, 14, 15, 16, 17, 18, 19, 20 or 21, more particularly 1, 9, 16, 18, 19, 20 or 21, preferably 18, 19, 20 or 21, and more preferably 20: [Tables II] No. Structure Chemical Name 1 A h H '"Y H N-éthyl-2-thioxo-1,2-dih ydropyridine-3-carboxa mide 2 x . / y S N-méthyl-2-thioxo-1,2-d ihydropyridine-3-carbox amide 3 ,Yx‘ vx-, Y ""X z" 'z" N-octyl-2-thioxo-1,2-dih ydropyridine-3-carboxa mide 4 ,-x ''*X Y x^ ->y \^o:Y^y A”'” -•Y: N-benzyl-2-thioxo-1,2-d ihydropyridine-3-carbox amide 5 _ — / Z / xX / \ V y—x:^x.'' X.S' ■ N-phényl-2-thioxo-1,2-d ihydropyridine-3-carbox amide 6 n i A. A. x xy >r v-- H -H N-cyclohexyl-2-thioxo-1 ,2-dihydropyridine-3-car boxamide 7 N-[2-(4-méthoxyphényl) éthyl]- ... i ... £ î w if ■-<v v x-" t..A 2-thioxo-1,2-dihydropyri dine- 3-carboxamide 8 H xk 3. N - (2-méthy Ipropy 1) -2-thi oxo-1,2-dihydropyridine-3-carboxamide 9 Y f< ‘■'M"' X"'"' :; !; $ M’ \ ■ Yy'X N-pentyl-2-thioxo-1,2-di hydropyridine-3-carboxa mide 10 N-nonyl-2-thioxo-1,2-di hydropyridine-3-carboxa mide 11 P X'^ A K N-(2-hydroxyéthyl)-2-thi oxo-1,2-dihydropyridine-3-carboxamide X OH 12 1 VY s ’: H N,N-diéthyl 2-mercapton icotinamide 13 QXX H-- ,-¼ 4 x'— N-ethyl-N-(2-hydroxyethyl)- 2-thioxo-1,2-dihydropyridin- 3-carboxamide 14 -SO N-(2,3-dihydroxypropyl )- 2-thioxo-1,2-dihydropyridin- 3-carboxamide 15 O y ..........J y X N-( 1,3-dihydroxypropan -2-yl)- 2-thioxo-1,2-dihydropyridin- 3-carboxamide 16 JA .Av A AA XA H / y N- [(2-thioxo-1,2-dihydropyridin- 3-yl)carbonyl]ethyl alaninate 17 ery N- [(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]ethyl alaninate 18 ethyl N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)carbonyl]glycinate X^X^ OS -O'' 'OH N-methyl-N-[(2-thioxo-1,2-dihydropyridin-3-yl)ca rbonyl]glycine 22 ■SH ^:v. X^ XX •'■■'x YY' N,N-bis(2-hydroxyéthyl )- 2-thioxo-1,2-dihydropyri dine- 3-carboxamide 23 N-(3-méthoxypropyl)-2-t hioxo-1,2-dihydropyridin e-3-carboxamide

4.

5. Composition according to any one of claims 1 to 3, wherein the quantity of the (a) first compound(s) of the composition is from 0.001% to 10% by weight, preferably from 0.005% to 5% by weight, and more preferably from 0.01% to 3% by weight, relative to the total weight of the composition. Composition according to any one of claims 1 to 4, wherein the (b) second compound is represented by the following chemical formula (II): [Chem. 13] SR (II) in which: - X represents a group -O-R', -OM or -NR'R"; - R, R' and R" represent, simultaneously or independently of each other, a hydrogen atom, an alkyl, alkenyl or acyl group in CrCi8, the alkyl, alkenyl or acyl group being linear or branched, optionally substituted by at least one substituent chosen from the hydroxyl group, possibly esterified, halogen atoms, the carboxyl group and its derivatives, and the amine group and its derivatives, and possibly containing in the chain at least one heteroatom such as O and S; and M represents a cation such as a metallic cation.

6. Composition according to claim 5, wherein the groups R, R' and R" of chemical formula (II) denote, simultaneously or independently of each other, a hydrogen atom or an ethyl, acetyl or acyl group, and preferably R denotes a hydrogen atom or an ethyl, acetyl or acyl group, and X denotes NH2

7. Composition according to claim 5 or 6, wherein the (b) second compound is ergothioneine.

8. Composition according to any one of claims 1 to 7, wherein the quantity of the (b) second compound(s) in the composition is from 0.001% to 15% by weight, preferably from 0.005% to 10% by weight, and more preferably from 0.01% to 5% by weight, relative to the total weight of the composition.

9. A cosmetic process, preferably a bleaching process, for a keratinous material, preferably skin, comprising the step of: applying to the keratinous material the composition according to any one of claims 1 to 8.

10. Use of (b) at least one second compound selected from ergothioneine and its derivatives in a composition comprising (a) at least one first compound selected from the compounds of formula (I) below, the tautomers of formula (I') below, their salts, their solvates, such as their hydrates, their optical isomers, their racemates, and mixtures thereof: [Chem. 14] in which - Ri designates a radical chosen from a) a hydrogen atom, and b) a linear saturated alkyl group in the form of Ci-Cio or branched in the form of C3-CiO optionally substituted by one or more groups, which may be identical or different, chosen from i) -O-R3, and ii) -S-R3, and - R2 denotes a radical chosen from a) a hydrogen atom, (b) a linear saturated hydrocarbon group in C1-C12 or a branched hydrocarbon group in C3-C12 or a cyclic hydrocarbon group in C3-C8, optionally substituted by one or more groups, which may be the same or different, selected from i) -O-R3, ii) -S-R3, iii) -C(O)-O-R3, and (iv) an aryl group in the C5-C12 position, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in the C1-C8 position, and c) an aryl group in the C5-C12 position, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in the C12 position -C8 in which - R3 designates a radical chosen from a) a hydrogen atom, and b) a linear saturated alkyl group in the C1-C10 range or a branched alkyl group in the C3-C10 range in order to stabilize the (a) first compound(s).