COSMETIC COMPOSITION COMPRISING THIOPYRIDINONE COMPOUNDS, A REDUCING AGENT AND AN AMINO ACID

Abstract

COSMETIC COMPOSITION COMPRISING THIOPYRIDINONE COMPOUNDS, A REDUCING AGENT, AND AN AMINO ACID. The present invention relates to a composition, preferably a cosmetic composition, comprising at least one thiopyridinone compound of formula (I) or formula (I'), with at least one reducing agent of formula (II) and at least one amino acid of formula (III). The composition of the present invention provides a lightening or depigmenting effect on keratinous material, preferably skin. The composition comprising a thiopyridinone compound of formula (I) or formula (I') offers increased stability of the thiopyridinone compound of formula (I) or formula (I'). Figure for the abstract: none

Description

Title of the invention: COSMETIC COMPOSITION COMPRISING THIOPYRIDINONE COMPOUNDS, A REDUCING AGENT AND AN AMINO ACID FIELD OF INVENTION

[0001] The present invention relates to the field of cosmetics, in particular cosmetic compositions. More particularly, the present invention relates to a cosmetic composition comprising a thiopyridinone compound, a reducing agent, and an amino acid. The present invention also relates to cosmetic compositions for whitening or depigmenting keratinous material, namely skin. CONTEXT OF THE INVENTION

[0002] Many people develop brown spots or marks on their skin over the course of their lives, particularly on the face and hands. These brown spots or marks are due to the presence of a high concentration of melanin in the keratinocytes on the surface of the skin.

[0003] For the treatment of these pigmentation spots, it is necessary to use harmless topical depigmenting substances that offer good efficacy and may also have a skin-lightening effect. Certain organic compounds such as arbutin, niacinamide, and kojic acid are known as skin-depigmenting agents.

[0004] It is known that certain thiopyridinone compounds exhibit good depigmenting activity, even at low concentrations, for example those cited in documents WO2012 / 080075 and WO2017 / 102349. The thiopyridinone compound can show strong depigmenting or lightening effects by reducing melanin production. Nevertheless, there is a need to develop a cosmetic composition comprising a thiopyridinone compound with increased stability, to confer skin lightening and whitening effects. Summary of the invention

[0005] This disclosure relates to a composition, preferably a cosmetic composition, comprising one or more thiopyridinone compounds of formula (I) or (I'), one or more amino acids, and one or more reducing agents, wherein the stability, preferably the thermal stability and / or photostability, of the thiopyridinone compound(s) is increased. The inventors have discovered, surprisingly, that the combination of amino acid(s) and reducing agent(s) improves the stability, preferably thermal stability and / or photostability, of the compound of formula (I) or (I1) in the composition.

[0006] The present invention proposes a composition, preferably a cosmetic composition comprising: I. at least one compound chosen from a compound of formula (I) below, its tautomer of formula (!') below, their salts, solvates, hydrates,

[0008] R i designates a radical chosen from:

[0009] a) a hydrogen atom;

[0010] 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, selected from:

[0011] i)-O-R3;

[0012] ii) -S-R3;

[0013] R 2 designates a radical chosen from:

[0014] a) a hydrogen atom;

[0015] b) a linear saturated CrCi2 hydrocarbon group or a C3-Ci2 branched hydrocarbon group or a C3-C8 cyclic hydrocarbon group, optionally substituted by one or more groups, which may be identical or different, selected from:

[0016] i) -O-R3;

[0017] ii) -S-R3;

[0018] iii) -C(O)-O-R3 ;

[0019] iv) an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in Ci-C8 and

[0020] a) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in CrC8;

[0021] R 3 designates a radical chosen from: a. a hydrogen atom and

[0022] b) a linear saturated alkyl group in Ci-Cio or branched in C3-CiO;

[0023] (II) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates O (II) R--S--O"M +

[0024] in which

[0025] X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen;

[0026] m is equal to 0 or 1;

[0027] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0028] R a group selected from: i. -OH,

[0029] ü) -O-M'+ with M'+ as defined previously for M+,

[0030] iii) o —[SJ-—S--Q~ M"”

[0031] in which,

[0032] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0033] • m' is equal to 0 or 1, preferably 1;

[0034] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0035] • M' '+ is such as defined previously for M+, and M+, M'+, M' '+ are identical or different, preferably identical;

[0036] and

[0037] (III) at least one amino acid preferably of formula (III), its enantiomers, salts or solvates such as hydrates (HD

[0039] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0040] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0041] and

[0042] c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0043] or

[0044] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0045] and

[0046] R b represents one of the following elements: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-Ci2 or cyclic in C3-C8.

[0047] Another aspect of the present invention proposes a method for treating a keratinous material, the method comprising: the application of a composition comprising: I. at least one compound chosen from a compound of formula (I) below, its tautomer of formula (F) below, their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof: OQ II,-x. AAA AA N"' 4 y X AS ' k J- "SH î H Formula (I) Formula (!')

[0048] in which

[0049] R i designates a radical chosen from: a. a hydrogen atom; 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; ii. -S-R3;

[0050] R 2 designates 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 identical or different, chosen from: i. -O-R3; ii. -S-R3; iii. -C(O)-O-R3 ; iv. an aryl group at C5-C12, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in CrC8 and

[0051] c) an aryl group in C5-C12, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in Ci-C8;

[0052] R 3 designates a radical chosen from: a. a hydrogen atom and b. a linear saturated alkyl group in C1-C10 or branched in C3-C10;

[0053] (II) at least one reducing agent of formula (II) its mesomeric forms and its solvates such as hydrates O (II) R--S--OM *

[0054] in which

[0055] X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen;

[0056] m is equal to 0 or 1;

[0057] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0058] R a group selected from:

[0059] i) -OH,

[0060] H) -O-M'+ with M'+ as defined previously for M+,

[0061] iii) o

[0062] in which,

[0063] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0064] • m' is equal to 0 or 1, preferably 1;

[0065] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0066] • M' '+ is such as defined previously for M+, and M+, M'+, M' '+ are identical or different, preferably identical;

[0067] and

[0068] (III) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates (III)

[0069] in which

[0070] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0071] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0072] and

[0073] c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0074] or

[0075] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0076] and

[0077] R b represents one of the following elements: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8,

[0078] on keratinous material, preferably skin.

[0079] Another aspect of the present invention proposes a use of the composition comprising: I. at least one compound chosen from a compound of formula (I) below, its tautomer of formula (F) below, their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof: OR It „ A K'? 1 I 4, ISI 'N" 'SHH Formula (I) Formula (!')

[0080] in which

[0081] R 1 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in C1-C10 or branched in C3-C10 optionally substituted by one or more groups, which may be identical or different, chosen from: i. -O-R3 and ii. -S-R3;

[0082] R 2 denotes a radical chosen from: a. a hydrogen atom; b. a linear saturated CrCi2 hydrocarbon group, or a C3-Ci2 branched hydrocarbon group, or a 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 ; iv. 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 and c. an aryl group in C5-C12, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals;

[0083] R 3 designates a radical chosen from: a. a hydrogen atom and b. a linear saturated alkyl group in C1-C10 or branched in C3-C10;

[0084] (II) at least one reducing agent of formula (II) its mesomeric forms and its solvates such as hydrates O (II) R.........S........OMT

[0085] in which

[0086] X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen;

[0087] m is equal to 0 or 1;

[0088] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0089] R a group chosen from:

[0090] i) -OH,

[0091] ü) -O-M'+ with M'+ as defined previously for M+,

[0092] iii) o —S--Q

[0093] in which,

[0094] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0095] • m' is equal to 0 or 1, preferably 1;

[0096] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0097] • M' '+ is such as defined previously for M+, and M+, M'+, M' '+ are identical or different, preferably identical;

[0098] and

[0099] (III) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates

[0100] in which

[0101] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0102] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(Ci-Ci2) and v. an optionally substituted C3-C8 heterocyclyl,

[0103] and

[0104] c) -C(O)-R d, wherein Rd is selected from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0105] or

[0106] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0107] and

[0108] R b represents one of the following: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8,

[0109] for lightening or depigmenting keratinous material, preferably skin.

[0110] Another aspect of the present invention proposes the use of a combination of

[0111] (I) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates O (H) rxi

[0112] in which

[0113] X represents a heteroatom selected from oxygen or sulfur, preferably oxygen;

[0114] m is equal to 0 or 1;

[0115] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0116] R represents a group chosen from:

[0117] i)-OH,

[0118] ü) -O-M'+ with M'+ as defined previously for M+,

[0119] iii) o

[0120] in which,

[0121] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0122] • m' is equal to 0 or 1, preferably 1;

[0123] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0124] • M' '+ is such as defined previously for M+, and M+, M'+, M”+ are identical or different, preferably identical and

[0125] (II) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates

[0126] in which

[0127] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0128] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0129] and

[0130] c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0131] or

[0132] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0133] and

[0134] R b represents one of the following: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8>

[0135] in a composition comprising at least one compound selected from the compounds of formula (I), its tautomer of formula (I1), their salts, optical isomers, racemates, solvates, hydrates or mixtures thereof: O fYY* U <4^ N 'S ' HO a / VA, H Formula (IJ Formula (F)

[0136] formulas (I) and (I') in which:

[0137] R 1 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in C1-C10 or branched in C3-C10 optionally substituted by one or more groups, which may be identical or different, chosen from: i. -O-R3; ii. -S-R3;

[0138] R 2 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 identical or different, chosen from: i. -O-R3; ii. -S-R3; iii. -C(O)-O-R3 ; iv. an aryl group at C5-Ci2, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in CrC8;

[0139] c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals; and

[0140] R 3 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in Ci-Cio or branched in C3-CiO, to stabilize the compound of formula (I), its tautomer of formula (!'), their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof, in the composition.

[0141] These features, aspects, and advantages, as well as others, of the present subject matter will be better understood by reference to the following description and the attached claims. The purpose of this summary is to present a selection of concepts in a simplified form. This summary is not intended to identify key features or essential features of the claimed subject matter, nor to be used to limit the scope of the claimed subject matter. DESCRIPTION OF THE INVENTION

[0142] A person skilled in the art will be aware that this disclosure is subject to variations and modifications other than those specifically described. It should be understood that this disclosure includes all such variations and modifications. The disclosure also includes all such steps, features, compositions, and compounds designated or indicated in this patent memorandum, individually or collectively, and any combination of one or more of these steps or features.

[0143] Definitions

[0144] For convenience, before describing this disclosure in more detail, certain terms used in the patent memorandum and examples are defined here. These definitions should be read in light of the rest of the disclosure and understood as by a person skilled in the art. The terms used in this document have meanings recognized and known to a person skilled in the art, However, for reasons of convenience and completeness, specific terms and their meanings are presented below.

[0145] The terms “include” and “comprising” are used in an inclusive and open sense, meaning that additional elements may be included. They are not intended to be interpreted as “consists solely of”.

[0146] The expression "at least one" is used to mean one or more and therefore includes individual components as well as mixtures / combinations.

[0147] Throughout this patent brief, unless the context otherwise requires, the term "include", and variations such as "includes" and "comprising", shall be understood to imply the inclusion of any element or step or group of elements or steps stated, but not the exclusion of any other element or step or group of elements or steps.

[0148] The term "including" is used to mean "including, but not limited to". "Including" and "including, but not limited to" are used interchangeably.

[0149] The term "INCI" is an abbreviation for International Nomenclature of Cosmetic Ingredients, which is a system of names provided by the International Nomenclature Committee of the Personal Care Products Council to describe the ingredients of personal care products.

[0150] All percentages, parts, and ratios are based on the total weight of the compositions in this disclosure, unless otherwise stated. Ratios, concentrations, quantities, and other numerical data may be presented herein in a range format. It should be understood that this range format is used solely for convenience and conciseness and should be interpreted flexibly as including not only the numerical values ​​explicitly cited as the range limits, but also as including all individual numerical values ​​or subranges encompassed within that range as if each numerical value and subrange were explicitly cited.For example, a percentage range by weight of about 0.01% to 10% should be interpreted as including not only the explicitly quoted limits of about 0.01% to about 10%, but also as including sub-ranges, such as 0.02% to 0.05%, 1% to 10%, and so on, as well as individual quantities, including fractional quantities, within the specified ranges, such as 1.5%, 5.3% and 9.25%, for example.

[0151] For the purposes of this disclosure, unless otherwise indicated: a. A "linear saturated hydrocarbon group in CrCi2 or branched in C3-Ci2" is equivalent to a "linear (C1-C12) or branched (C3-C12) alkyl group" which corresponds to a linear saturated hydrocarbon group in C1-C12 or branched at C3-Ci2, and preferably to a linear hydrocarbon group in the Ci-Cio or branched at C3-C10, more preferably to a linear hydrocarbon group in the Ci-C6 or branched at C3-C6; preferably, the linear or branched groups may be selected from the methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl groups. More preferably, the linear or branched saturated alkyl groups may be selected from the methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl and octyl groups, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl; b. A saturated hydrocarbon group "C3-C8 cyclic" is a mono- or bicyclic cycloalkyl group containing 3 to 8 carbon atoms and, in particular, is a monocyclic cycloalkyl group having C5 to C7 atoms, such as a cyclohexyl group, c. an "alkoxy radical" is an alkyl-oxy radical in which the alkyl radical is a linear or CrCi6-branching hydrocarbon radical and, preferably, a Ci-C8 radical; when the alkoxy group is optionally substituted, this implies that the alkyl group is optionally substituted as defined herein; d. an 'aryl' group represents a carbon-based group, monocyclic or bicyclic, fused or unfused, 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, a biphenyl, a naphthyl, more preferably a phenyl group; e. The expression "at least one" is equivalent to the expression "one or more"; and f. The term "included" for a concentration range means that the limits of that range are included within the defined range.

[0152] The salts of compounds of formula (I), (!'), (la) or (la') include conventional non-toxic salts of said compounds, such as those formed from an organic or inorganic acid or an organic or inorganic base.

[0153] As salts of compounds of formula (I), (P), (la) or (la1), mention may be made of the addition of the compound of formula (I) to i. 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; or ii. an organic base such as a primary, secondary, or tertiary alkylamine, for example, triethylamine or butylamine. This primary alkylamine, secondary or tertiary may include one or more nitrogen and / or oxygen atoms and may therefore include, for example, one or more alcohol functions; examples include 2-amino-2-methylpropanol, ethanolamine, triethanolamine, 2-dimethylaminopropanol, 2-amino-2-(hydroxymethyl)-1,3-propanediol and 3-(dimethylamino)propylamine.

[0154] Other examples include amino acid salts, for instance lysine, arginine, guanidine, glutamic acid, and aspartic acid. Advantageously, the salts of compounds of formula (I) (when they include a carboxy group) can be selected from alkali metal or alkaline earth metal salts such as sodium, potassium, calcium, or magnesium salts and ammonium salts.

[0155] A "salt of an organic or inorganic acid" is more particularly chosen from 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.

[0156] 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.

[0157] Optical isomers of formula (I) or (!') are, in particular, enantiomers and diastereomers.

[0158] The mesomeric forms of formula (II) represent isomers of compounds of formula (II) resulting from the delocalization of electrons around heteroatoms such as oxygen and / or sulfur.

[0159] For the purposes of the present invention, the term "guanidino group" refers to guanidine with at least one less hydrogen atom. The guanidino group is linked to the rest of the compound by the amino nitrogen of guanidine. The guanidino group includes, but is not limited to, -N(H)-C(=NH)-NH2, -N(H)-C(=NH)-(H)N-, or -NC(=NH)-NH2, which may optionally be substituted. Preferably, the guanidino group refers to N(H)-C(=NH)-NH2.

[0160] The term "heterocyclyl" refers to a molten or unmolten monocyclic, bicyclic, or polycyclic ring compound, which may be saturated, unsaturated, or partially unsaturated, comprising 3 to 8 carbons with at least one heteroatom selected from nitrogen, sulfur, and oxygen. Preferably, the heterocyclyl comprises one to four heteroatoms and 3 to 5 carbon atoms, which may be unsaturated.

[0161] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by a person skilled in the art of this disclosure. Although all processes and materials similar or equivalent to those described herein may be used in the practice or testing of the disclosure, preferred processes and materials are now described.

[0162] This disclosure shall not be limited in scope by the specific embodiments described herein, which are intended for illustrative purposes only. Functionally equivalent products, compositions, and processes clearly fall within the scope of the disclosure as described herein. Composition

[0163] The present invention proposes a composition, preferably a cosmetic composition comprising: I. at least one compound chosen from a compound of formula (I) below, its tautomer of formula (F) below, their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof: O y 1 '-s ' HG i .¾ x ​​"N h JN" 'S ï H Formula (I) Formula (!')

[0164] in which

[0165] R i designates a radical chosen from:

[0166] a) a hydrogen atom;

[0167] b) a linear saturated alkyl group in C1-C10 or branched in C3-C10 optionally substituted by one or more groups, which may be identical or different, selected from:

[0168] i) -O-R3;

[0169] ii) -S-R3;

[0170] R 2 denotes a radical chosen from:

[0171] a) a hydrogen atom;

[0172] 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, selected from:

[0173] i) -O-R3;

[0174] ii) -S-R3;

[0175] iii) -C(O)-O-R3 ;

[0176] iv) 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 and

[0177] c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in CrC8;

[0178] - R 3 designates a radical chosen from:

[0179] a) a hydrogen atom and

[0180] b) a linear saturated alkyl group in Ci-Cio or branched in C3-CiO;

[0181] (II) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates O (II) pL

[0182] in which

[0183] X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen;

[0184] m is equal to 0 or 1;

[0185] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0186] R a group chosen from:

[0187] i) -OH,

[0188] ü) -O-M'+ with M'+ as defined previously for M+,

[0189] iii) o —FS]—S--G' ' p II

[0190] in which,

[0191] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0192] • m' is equal to 0 or 1, preferably 1;

[0193] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0194] • M' '+ is such as defined previously for M+, and M+, M'+, M' '+ are identical or different, preferably identical;

[0195] and

[0196] (III) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates

[0197] in which

[0198] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0199] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0200] and

[0201] c) -C(O)-R d, in which Rd is selected from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0202] or

[0203] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0204] and

[0205] R b represents one of the following: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-Ci2 or cyclic in C3-C8.

[0206] The composition, preferably a cosmetic composition according to an embodiment of the present invention, includes at least one compound of formula (I) or (P), referred to as a "thiopyridinone-type compound" or "thiopyridinone compound." It may be preferable for the present invention to provide cosmetic compositions that include a combination of a thiopyridinone-type compound (I) or (I') with at least one reducing agent of formula (II) and at least one amino acid, which enhances the stabilization, preferably thermal stabilization and / or photostabilization, of the thiopyridinone compounds and the cosmetic composition comprising them. The "stability" of the thiopyridinone compound can be determined by the change in the amount of the thiopyridinone compound in the composition according to the present invention over a certain period of time.The "thermal stability" of the thiopyridinone compound can be determined by observing the change in the amount of thiopyridinone in the composition according to the present invention over a certain period of time, particularly when the composition is maintained for a relatively long period, such as two weeks, at room temperature or even at elevated temperatures such as above 40°C. The "photostability" of the thiopyridinone compound can be determined by observing the change in the amount of thiopyridinone in the composition according to the present invention after exposure to light. Increased "stability," "thermal stability," or "photostability" means that the change in the amount of thiopyridinone over time is more limited.

[0207] In some embodiments, the combination of at least one reducing agent and at least one amino acid improves the stabilization, preferably thermal stabilization and / or photostabilization, of the compound of formula (I) or (I1) in the composition. In other embodiments, the composition according to the present invention exhibits increased stability, preferably thermal stability and / or photostability, of the thiopyridinone compound of formula (I) and (I1) herein. In some embodiments, the composition according to the present invention exhibits increased stability of the compound of formula (I) or (I') under prolonged storage at room temperature. In some embodiments, the composition according to the present invention exhibits increased stability of the compound of formula (I) or (I') even when the composition is maintained and stored for a longer period, such as two to three weeks, at elevated temperatures such as 40 to 60 °C.In yet another embodiment, the increased stability of the compound of formula (I) or (I1) in the composition provides improved bioavailability to produce prolonged lightening or depigmenting effects on keratinous matter.

[0208] The present invention, according to one embodiment, provides methods for improving the stability of a thiopyridinone (I) or (I1) type compound in Cosmetic compositions useful for treating keratinous material, such as human facial and neck skin. In some embodiments, the present invention provides cosmetic skin treatment methods comprising applying the cosmetic composition of the present invention to the skin to produce a lightening or whitening effect. These cosmetic compositions are also useful in non-therapeutic methods for treating brown spots and uneven skin texture. Thiopyridinone compound

[0209] The composition, preferably a cosmetic composition according to an embodiment, includes:

[0210] i) at least one compound selected from a compound of formula (I) below, its tautomer of formula (!') below, their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof: OOH Formula 0) Format (f)

[0211] in which

[0212] R i designates a radical chosen from:

[0213] a) a hydrogen atom;

[0214] 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, selected from:

[0215] i) -O-R3;

[0216] ii) -S-R3;

[0217] R 2 denotes a radical chosen from:

[0218] a) a hydrogen atom;

[0219] 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 identical or different, selected from:

[0220] i) -O-R3;

[0221] ii) -S-R3;

[0222] iii) -C(O)-O-R3 ;

[0223] iv) an aryl group at C5-C12, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals at C1-C8 and

[0224] 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;

[0225] R 3 designates a radical chosen from:

[0226] a) a hydrogen atom and

[0227] b) a linear saturated alkyl group in Ci-Cio or branched in C3-CiO;

[0228] The compounds used according to the present invention therefore correspond to the formula (I) or the tautomer (!') below or to their salts, their optical isomers, racemates, and / or solvates such as hydrates and their, alone or in mixture. (I) (D

[0229] In these formulas (I) and (!'):

[0230] R i designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in the form of C1-C10 or branched in the form of C3-C10 optionally substituted by one or more groups, which may be identical or different, chosen from:

[0231] i)-O-R3;

[0232] ii) -S-R3;

[0233] R 2 designates 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

[0234] i) -O-R3;

[0235] ii) -S-R3;

[0236] iii) -C(O)-O-R3 ;

[0237] iv) an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or one or more CrC8 alkoxy radicals; and

[0238] c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals

[0239] in which

[0240] R 3 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in Ci-Cio or branched in C3-CiO;

[0241] The compound (!') is the tautomeric form of compound (I) when a tautomeric equilibrium exists according to the following scheme:

[0242] It may be preferable for Ri to represent a hydrogen atom.

[0243] It may be preferable for Ri to represent a linear (Ci-Ci0) alkyl group or in (C3-C10) branched, in particular a linear (C1-C6) or branched (C3-C6) alkyl group, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably ethyl. In particular, said alkyl group of Rin' is unsubstituted.

[0244] It may be preferable for R2 to represent a hydrogen atom.

[0245] It may be preferable for R2 to represent a linear alkyl group (in C1-C10) or branched (in C3-C10), in particular a linear (in Ci-C6) or branched (in C3-C6) alkyl group, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably a methyl or ethyl group; said alkyl group of R2 not being substituted.

[0246] It may be preferable that R2 represent a linear (C1-C10) or branched (C3-C10) alkyl group, in particular a linear (C1-C6) or branched (C3-C6) alkyl group, such as methyl, ethyl, n-pentyl, n-nonyl, 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 is substituted with one or two groups selected from i), ii) and iii), more preferably with one or two groups selected from i) and iii), or better yet substituted with a group iii) such as a carboxy.

[0247] Another variant for the radical R2 is that said alkyl group is substituted by a group iv) in particular substituted by a phenyl group.

[0248] It may be preferable that R2 represents a cycloalkyl group (in C3-C8), preferably a cycloalkyl group (in C5-C7) such as cyclohexyl.

[0249] It may be preferable that R2 represents an aryl group in C5-Ci2 optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in CrC8, preferably a phenyl group in particular unsubstituted.

[0250] It may be preferable for R3 to represent a hydrogen atom.

[0251] It may be preferable that R3 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 the methyl group.

[0252] It may be preferable that the compounds of formula (I) and the tautomer (I') or their salts, their optical isomers, racemates, and / or solvates such as hydrates and theirs, alone or in mixture;

[0253] have the following meanings:

[0254] R 1 designates a radical chosen from: a. a hydrogen atom; 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 identical or different, chosen from: i. -O-R3; ii. -S-R3;

[0255] preferably optionally substituted by one or more groups i);

[0256] R 2 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C10 or branched in C3-C10 or cyclic in C3-C8 such as C3 C6, optionally substituted by one or more groups, which may be identical or different, chosen from: i. -O-R3; ii. -SR3; iii. -C(O)-O-R3 ; 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;

[0257] preferably substituted by one or more groups selected from i) and iii), preferably iii) such as carboxy;

[0258] R 3 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in C1-C6 or branched in C3-C6.

[0259] It may be preferable that the compounds of formula (I) and the tautomer (I') or their salts, their optical isomers, racemates, and / or solvates such as hydrates and their, alone or in mixture, have the following meanings:

[0260] R 1 designates a radical chosen from: a. a hydrogen atom;

[0261]

[0262]

[0263]

[0264]

[0265]

[0266]

[0267]

[0268]

[0269] b. a linear saturated alkyl group in Ci-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; R 2 denotes a radical chosen from: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C10 or branched in C3-C10 or cyclic in C3-C8 as in C5-C6, optionally substituted by one or more groups, which may be identical or different, chosen from: i. -O-R3; ii. -C(O)-O-R3 ; iii. an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in Ci-C4; R 3 designates 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. It may be preferable that the compounds of formula (I) and the tautomer (!') or their salts, their optical isomers, racemates, and / or solvates such as hydrates and their, alone or in mixture; have the following meanings: Ri is a hydrogen atom and R 2 denotes a radical chosen from: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C5 or branched in C3-C5 or cyclic in C3-C8 such as in C5-C6, substituted by one or more groups, which may be identical or different, selected from v) —C(O)-O-R3, preferably substituted by a group iii) —C(O)-O-R3 and R2 is even more preferentially a linear saturated CrC4 hydrocarbon group or a C3-C4 branched group substituted by a iii) -C(O)-OR3 group and R 3 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated CrC4 or C3-C4 branched alkyl group such as methyl or ethyl. It may be preferable that the compounds of formula (I) and the tautomer (I') be chosen from the compounds of formula (la) and also their tautomers of formula (la') below, their salts, their solvates and their optical isomers, and their racemates, alone or in mixture:

[0270] In formulas (la) and (la'), Ri and R3 have the same meaning as for compounds of formula (I) and (!') 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.

[0271] Among the compounds of formula (I), the following compounds are preferably used, and their tautomer or their salts, their optical isomers, racemates, and / or solvates such as hydrates and their derivatives, alone or in mixtures: Structure Kom chemical K° CAS 1 U N-ethy1-2-thisxo- 1 ;2-dshydropyridîf3e- 3-cafboxamkfe 91859-75-5 2 x \\ x'; SX N-métby^2.4hi:Oxo- 1 ..2-dîhÿdrapyndme- 3-cadjoxamide 91859-74-4 3 N-benzyi-2-th®xo- 1,2-Æhycfrapyndme-3-cariîoxamKfe' 91859-7S-9 5 ...... % f A  JHA<4. N-cyctehexyt-24hiaxo- 1 ..2-ddiydrQpytidme-3-carijoxamkfe 91859-78-8 IX{2-(4-meth£5xyphenyl) ^^-2^09(0- 1 ..2-àhydrQpyrjdjns- 3-catbaxamide 923682-88-6 8 N-[2-methylpropyl]-24-hydroxy-12-hydroxypyridine-3-carboxiamide 1100027-78-9 9 M-phenyl-24-hydroxy-1,2-hydroxypyridine-3-carboxiamide 330667-57-7 10 fY N-fluoro-2-thioxo-1,2-hydroxypyridine-3-carboxamide 1031149-44-6 11 0 x -^--:xs >< N-(2-hydroxypropyl)-2-thio-1,2-hydroxypyridine-3-carboxamide 12 C -¾. HN^IM 2-mercaptopropyl 13 X' / X. U " ï / \ ; i î / \, V 'x^ ^■""■"ÛH MWrN-{24rydrexyéîhyr)-2-thfâxc- 1,3-dîhydropytidsne-3-ca^jaxamide 14 ■■.y •} <> N423-cW <toyF<W$- 2-thiexo- 1,2-<Shyctopyrâfi^ icætXKæÉMe 15 f^-{1 ;.3-rJhydrQKÿ'pïspan-2-yî)-2-®e> '.ï3- 1,2-^hy dropÿndme- 3-Œfbûxarsiide 16 HCI^-K2:4hsox6- d'éWls 17 y-.-■ XX K4(2-ihffi <a- 1 ..2-dàhÿtopyïj^ 18 N-næW4HC2^ 1,2-dshy topyWn-3-yfj d'é^yfe 19 Xy■' 1 .ï-dshy'dropyddsn-S-yl) .Œta^aiSÈSWs d’éWle 2G yÀ-X / ' j T " T H-K2-lhsO'C- 1 ^-d^ydropyndln-a-yl) 21 XX f T Y T l> d3hydrapraphii> 2? .O f s- 24biQKD- 1,2-^hy droj^ndme- 3-eafi50xafsi^s 23 * 2-$wo- 1,2-dhy stapyïkisne- 3-carboKafni£te 24 ri .s. ... „ T 1 "" N-bütyt-2-SâoKO- 3-cafto:arasde

[0272] Among these compounds, the following compounds are particularly preferred: K Structured Mom chemique N^CAS 1 : : H N-ê:ftyk2-iWicxo-1,2-®ÿ£ta3pyf^ 3-cafeoK®rede 91B5S-75-5 fsS-fné^-^-thiQXo- 1,2-cW$ixam WW'&'ca 91859-74-4 4 ><.. ^.-y ■N-tenzy-2-SHŒO-i ;2-®ÿ&opyntene-3-carbaxawde 91359-79-9 c> f- '" ”\ S ; •? ^-- ^5 N-cydd^eKykï-^i^^ i ,2-dshyÆopyddsne-3-carta <amjde 91359-78-8 7 s [ i àteH-feiaxo-1.2Æy^i^yï Kâne-, 3-castomiKSé 923W-SS-6 9 f'XX'XX'' ' N-pertÿ{-2-Si8CKG- 1 ^-d^î&îW'Wifi- 7-313-ca^xam6de N424iyto^fty$- 24hi8xo- 1.2-® y ^ropyslctae-a-ca&oxaiwJe 12 S. / ' X:x'' $; XCB;. N.WkWl 24îien^0^cütam^ 14 ' y ■'y^' '■■■•■ N42;34Shyto<yï»wJ> l^-cfasycaiw-. 3-eaîbsxajïiide 15 ..... A - M41 .Ml^axjçrapso-2-yl>2-tlwxo- 1 .a^W'âRW^Sne-3 <aîteæ®;fe 16 x ...-Y sx* “• \ H-g2-îhsoxo- 1.S-dshyctopyOtF^-yl) of ethyte 17 ff 'X n-K2-83mko- MnttM sl'ethyte XX Y 18 1 •' X-.X'' 19 v ,Y> 1f2-dàhy <toj$T^n-3-:^

[0273] More preferably, among these compounds, the following compounds are particularly preferred: Structure Chemical Name IF CAS 1 s Y -c N-êîhyC2-thioXQ-1,2^y&opyôsine-3-ca>'tean§cte 91859'75-5 9 <S5ÿ(&0{wfêne- 3-cæfcoxamMfe 330667-57- 7 16 ... A I' ... ( L ' < :< J 1,2-®ry dfapyïjü§n<ï^ d'êthyte 13 X. CX T T 1 .Z-Ayà’opyôà^S-yl) d’è^yte 19.. R.... . (X v T v :N-[(2-ïhMKQ-V- rfê&syle 20 A -CH ( Ir ï N-mé§8^-M(2-^i«xo- gaa»§gtyciœ

[0274] Even more preferentially, among these compounds, the following compounds are more particularly preferred: Chemical structure Ptom PF CAS 18 H 1,2-ctihytopyr^^ of ethyl 19 N-K2«oxo-12- 20 hh ^-[(2-8s^o-1.2-dthyj&opyr^^ carbony[]^yck>e 21 I [ 1 1 N-mé8*yi4^(24hi8x<^ 12-W &opyhdln-3-yl)

[0275] In a most preferred embodiment, the compound according to the present invention is as follows:

[0276] All the above compounds can be obtained by a chemical process known to a person skilled in the art, from commercially available reagents.

[0277] It may be preferable that the (1) thiopyridinone compound of formula (I) or (I1) can be prepared according to the process described, for example, in EP-A-3 390 363 or WO 2017 / 102349.

[0278] The (1) compound thiopyridinone may be an active ingredient or an active compound in cosmetic or dermatological products. The term active ingredient or 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 (1) thiopyridinone compound used in the present invention can function as a depigmenting, lightening, bleaching, or whitening agent, and thus the composition according to the present invention can be used as a lightening product or as a cosmetic composition for lightening keratinous material.

[0279] The (1) thiopyridinone compound may be used as an agent for depigmenting, lightening, bleaching or whitening the skin, body hair, eyelashes or hair, and also the lips and / or nails, and preferably the skin, in particular for removing pigmentation spots or age spots and / or as an anti-tanning agent.

[0280] In some embodiments, the amount of the (1) thiopyridinone compound(s) in the composition 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.

[0281] In some embodiments the amount of the (1) thiopyridinone compound(s) in the composition 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.

[0282] In certain embodiments, the quantity of the (1) thiopyridinone compound(s) in the composition according to the present invention may range from 0.01% to 10% by weight, preferably from 0.05% to 5% by weight, and more preferably from 0.1% to 3% by weight, relative to the total weight of the composition.

[0283] In some embodiments, the amount of the (1) thiopyridinone compound(s) in the composition may range from 0.01% to 10% by weight, preferably from 0.1% to 5% by weight and, more preferably, from 0.5% to 3% by weight, relative to the total weight of the composition.

[0284] It may be preferable for the composition according to the present invention to comprise (1) at least one thiopyridinone compound. Two (1) or more thiopyridinone compounds may be used in combination. Thus, a single type of (1) thiopyridinone compound or a combination of different types of (1) thiopyridinone compounds may be used.

[0285] The (1) thiopyridinone compound is 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: . M R-: 'N' " H cF W (H

[0286] In these formulas (I) and (!'):

[0287] R i designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in the form of C1-C10 or branched in the form of C3-C10 optionally substituted by one or more groups, which may be identical or different, chosen from:

[0288] i) -O-R3;

[0289] ii) -S-R3;

[0290] R 2 designates 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 identical or different, chosen from:

[0291] i) -O-R3;

[0292] ii) -S-R3;

[0293] iii) -C(O)-O-R3 ;

[0294] iv) an aryl group at C5-Ci2, optionally substituted by one or more hydroxyl groups and / or one or more CrC8 alkoxy radicals; and

[0295] c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals

[0296] in which

[0297] R 3 designates a radical chosen from: a. a hydrogen atom; b. a linear saturated alkyl group in Ci-Cio or branched in C3-Ci0. Reducing agent

[0298] The composition of the present invention according to one embodiment comprises at least one (2) reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates O (H) rxi

[0299] in which

[0300] X represents a heteroatom selected from oxygen or sulfur, preferably oxygen;

[0301] m is equal to 0 or 1;

[0302] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0303] R a group chosen from:

[0304] i) -OH,

[0305] ü) -O-M'+ with M'+ as defined previously for M+ and

[0306] iii) o

[0307] in which,

[0308] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0309] • m' is equal to 0 or 1, preferably 1;

[0310] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0311] • M' '+ is such as defined previously for M+, and M+, M'+, M”+ are identical or different, preferably identical.

[0312] In certain embodiments, the composition comprises at least one (2) reducing agent of formula (II) in which

[0313] X of formula (II) represents a heteroatom selected from oxygen or sulfur, preferably oxygen;

[0314] m of formula (II) is equal to 0 or 1;

[0315] M + of formula (II) is a cation, preferably of sodium or potassium;

[0316] R of formula (II) represents a group chosen from

[0317] i)-OH,

[0318] ü) -O-M'+ with M'+ as defined previously for M+ and

[0319] iii) o

[0320] in which,

[0321] • p is equal to 0 or 2;

[0322] • m' is equal to 0 or 1;

[0323] • X' is such that defined for X, preferably X' represents an oxygen atom; and

[0324] M+, M'+, M”+ are identical.

[0325] In certain embodiments, in which the (2) reducing agent of formula (II)

[0326] R represents a group chosen from:

[0327] i) -OH,

[0328] ü) -O-M'+ with M'+ and

[0329] iii) o

[0330] in which

[0331] • p is equal to 0 or 2;

[0332] • m' is equal to 0 or 1;

[0333] • X' represents an oxygen atom and

[0334] M+, M'+ and M”+ are identical and chosen from sodium or potassium.

[0335] In certain embodiments, in which the (2) reducing agent of formula (II)

[0336] X of formula (II) represents sulfur;

[0337] m of formula (II) is equal to 1;

[0338] M+ of formula (II) is sodium or potassium;

[0339] R of formula (II) represents a group chosen from i. -OH and ü. -O-M'+ with M'+,

[0340] M+ and M+ are identical

[0341] In certain embodiments, the compounds of formula (II) may be found in their delocalized or marginal mesomeric limiting forms,

[0342] when m = 0 therefore rs(ow>= g rS[=O)-ow

[0343] and

[0344] when m = 1, the mesomeric limiting forms are R—8(01^)(=^)^0 R—O"WR—S(=0)(X'W)m=0 ,

[0345] where, M+, M'+, M"+ are present to ensure the electroneutrality of the molecule of formula (II).

[0346] It may be preferable that the (2) reducing agent be chosen from sodium bisulfite, sodium metabisulfite, sodium sulfite, sodium thiosulfate, sodium sulfate, potassium metabisulfite, potassium sulfite, potassium thiosulfate, potassium sulfate or potassium tetrathionate.

[0347] It may be preferable that the (2) reducing agent be chosen from sodium bisulfite, sodium metabisulfite, sodium sulfite, sodium thiosulfate or sodium sulfate.

[0348] The composition of the present invention according to one embodiment comprises a reducing agent of formula (II) which may be in an amount of 0.01% by weight or more, preferably 0.02% by weight or more, and more preferably 0.03% by weight or more, relative to the total weight of the composition.

[0349] The composition of the present invention according to one embodiment comprises a reducing agent of formula (II) which may be in an amount of 2.0% by weight or less, preferably 1.0% by weight or less, and more preferably 0.05% by weight or less, relative to the total weight of the composition.

[0350] It may be preferable that the quantity of the (2) reducing agent in the anhydrous composition according to the present invention be from 0.01% to 2% by weight, preferably from 0.02% to 1.0% by weight and, better still, from 0.03% to 0.5% by weight, relative to the total weight of the composition. Amino acid

[0351] The third ingredient of the composition according to the invention is one or more amino acids, preferably of natural origin, in particular selected from alanine - ala, asparagine - asn, aspartic acid - asp, cysteine ​​- cys, glutamine - gin, glutamic acid - glu, glycine - gly, histidine - his, isoleucine - ile, leucine - leu, lysine - lys, methionine - met, phenylalanine - phe, proline - pro, serine - sér, threonine - thr, tryptophan - trp, tyrosine - tyr, valine - val and their optical isomers, their salts, their solvates such as hydrates and their combinations.

[0352] More preferably, at least one amino acid is of formula (III), its enantiomers, salts or solvates such as hydrates

[0353] in which

[0354] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0355] Ra and Rc independently represent one of the following elements: a. a hydrogen atom; b. a linear saturated hydrocarbon group in C1-C1 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. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0356] and

[0357] c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0358] or

[0359] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0360] and

[0361] R b represents one of the following: i. a hydrogen atom; ii. a linear saturated hydrocarbon group in C1-C12 or branched in C3-Ci2 or cyclic in C3-C8.

[0362] In some embodiments, the composition comprises at least one amino acid of formula (III), in which

[0363] Y of formula (III) is hydrogen;

[0364] R a and R c of formula (III) independently represent one of the following elements: 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 identical or different, chosen from: i. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(Ci-Ci2) and v. an optionally substituted C3-C8 heterocyclyl,

[0365] and

[0366] c) -C(0)-R d, in which Rd is chosen from the aminoalkyl in (Ci-Ci2), the alkyl in (CrC12) the alkoxy in (CrC12);

[0367] or

[0368] R a and R c of Formula (III) being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0369] and

[0370] R b of formula (III) represents one of the following: a. a hydrogen atom; b. a linear saturated hydrocarbon group in Ci-Ci2 or branched in C3-Ci2 or cyclic in C3-C8.

[0371] In certain embodiments, in which

[0372] R of formula (III) represents one of the following: a. a hydrogen atom; b. a linear saturated CrCi2 group optionally substituted by one or more groups, which may be the same or different, chosen from: i. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0373] R cde formula (III) represents one of the following elements:

[0374] a) a hydrogen atom;

[0375] b) -C(O)-R d, in which Rd is chosen from the aminoalkyl in (Ci-Ci2), the alkyl in (CrC12) the alkoxy in (CrC12);

[0376] or

[0377] R a and R c of Formula (III) being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0378] and

[0379] R b of formula (III) is a hydrogen atom

[0380] In certain embodiments, in which

[0381] R has formula (III) represents one of the following elements: a. a hydrogen atom; b. a linear saturated CrCi2 group optionally substituted by one or more groups, which may be the same or different, chosen from: i. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. Guanidino group and iv. alkyl -S-(CrC12);

[0382] R c of formula (III) represents a hydrogen atom;

[0383] or

[0384] Ra and Rc of formula (III) being combined together to form a heterocyclyl ring having 3 to 8 atoms and

[0385] R b of formula (III) represents a hydrogen atom.

[0386] In certain embodiments, in which

[0387] R has formula (III) represents one of the following elements: a. a hydrogen atom; b. a linear saturated CrCi2 group optionally substituted by one or more groups, which may be the same or different, chosen from: i. a hydroxy; ii. Carboxylated or carboxylate salts, in particular of alkali metal or alkaline earth metal, preferably sodium or potassium; and iii. -S-alkyl in CrCi2;

[0388] R c of formula (III) represents a hydrogen atom;

[0389] or

[0390] Ra and Rc of formula (III) being combined together to form a ring heterocyclyl having 3 to 8 atoms; and

[0391] R of formula (III) represents a hydrogen atom.

[0392] According to one embodiment of the invention, the amino acid(s) is / are chosen from the aliphatic amino acid(s) such as alanine, glycine, isoleucine, leucine, proline or valine, their enantiomers, their salts and solvates such as hydrates or their combinations, more preferably proline or glycine.

[0393] According to one embodiment of the invention, the acid or amino acid(s) is / are chosen from hydroxylic acid(s) such as serine and threonine, their enantiomers, their salts and solvates such as hydrates or their combinations, more particularly threonine.

[0394] According to one embodiment of the invention, the acid or amino acid(s) is / are chosen from the acid or amino acid(s) containing sulfur such as cysteine ​​and methionine, their enantiomers, their salts and solvates such as hydrates or their combinations, more particularly methionine.

[0395] According to one embodiment of the invention, the acid or amino acid(s) is / are chosen from acidic amino acid(s) such as aspartic acid and glutamic acid, their enantiomers, their salts and solvates such as hydrates or their combinations, more particularly aspartic acid.

[0396] It may be preferable that the amino acid of formula (III) be chosen from a) serine, b) methionine, c) proline, d) aspartic acid, e) glycine, their enantiomers, their salts and solvates such as their hydrates or their combinations.

[0397] The composition of the present invention according to one embodiment comprises an amino acid of formula (III) which may be in an amount of 0.01% by weight or more, preferably 0.1% by weight or more, and more preferably 0.2% by weight or more, relative to the total weight of the composition.

[0398] The composition of the present invention according to one embodiment comprises an amino acid of formula (III) which may be in an amount of 10.0% by weight or less, preferably 8.0% by weight or less, and more preferably 6.0% by weight or less, relative to the total weight of the composition.

[0399] It may be preferable that the quantity of the amino acid in the composition according to the present invention be from 0.01% to 10% by weight, preferably from 0.1% to 8.0% by weight and more preferably from 0.2% to 6% by weight, relative to the total weight of the composition. pH adjuster

[0400] The composition of the present invention according to one embodiment may include at least one pH adjuster (pH correcting agent). Two or more pH adjusters may be used in combination. Thus, a single type of pH correcting agent or a combination of different types of pH correcting agents may be used.

[0401] As a pH correcting agent, at least one acidifying agent and / or at least one alkaline agent may be used.

[0402] The acidifying agent may be a monovalent or polyvalent acid, such as divalent.

[0403] Acidifying agents may be, for example, mineral (inorganic) acids such as hydrochloric acid, sulfuric acid, phosphoric acid, or organic acids such as carboxylic acids, for example tartaric acid, citric acid and lactic acid, as well as sulfonic acids.

[0404] The alkalizing agent may be a monovalent or polyvalent base, such as divalent. Alkalizing agents may be mineral (inorganic) or organic, or hybrid.

[0405] Mineral alkalizing agents may be selected from aqueous ammonia; alkali metal carbonates or bicarbonates such as sodium or potassium carbonates and sodium or potassium bicarbonates; hydroxides of alkali metals such as sodium hydroxide and potassium hydroxide; and mixtures thereof.

[0406] Organic alkalizing agents may be selected from organic amines having a pKb at 25 °C of less than 12, preferably less than 10, and even more advantageously less than 6. It should be noted that this is the pKb corresponding to the highest basicity functional group. Furthermore, the organic amines do not include any alkyl or alkenyl fatty chain comprising more than ten carbon atoms.

[0407] The organic alkalizing agent may be chosen, for example, from alkanolamines, oxyethylenated and / or oxypropylenated ethylenediamines, amino acids and amine compounds of formula (A) below:

[0408] in which

[0409] W represents a divalent Ci-C6 alkylene radical optionally substituted by one or more hydroxyl groups or a Ci-C6 alkyl radical, and optionally interrupted by one or more heteroatoms such as O and N, and

[0410] Rx, Ry, Rz and R t, which may be identical or different, represent a hydrogen atom or an alkyl radical in Ci-C6, hydroxyalkyl in Ci-C6, or aminoalkyl in CrC6.

[0411] Examples of amine compounds of formula (A) that may be mentioned include 1,3-diaminopropane, 1,3-diamino-2-propanol, spermine and spermidine.

[0412] The term "alkanolamine" means an organic amine comprising a primary, secondary or tertiary amine function, and one or more linear or CrC8 branched alkyl groups bearing one or more hydroxyl radicals.

[0413] Alkanolamines such as monoalkanolamines, dialkanolamines or trialkanolamines comprising one to three identical or different C1-C4 hydroxyalkyl radicals may be suitable for the present invention. Among compounds of this type, monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N-dimethylaminoethanolamine, 2-amino-2-methyl-1,3-propanediol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol and tris(hydroxymethylamino)methane may be mentioned.

[0414] The amino acids that may be used are of natural or synthetic origin, in their L, D or racemic form, and comprise at least one acid function Specifically chosen from among the carboxylic acid, sulfonic acid, phosphonic acid, or phosphoric acid functional groups. Amino acids can be in neutral or ionic form.

[0415] Amino acids that can be used in the present invention include, in particular, aspartic acid, glutamic acid, alanine, arginine, ornithine, citrulline, asparagine, carnitine, cysteine, glutamine, glycine, histidine, lysine, isoleucine, leucine, methionine, N-phenylalanine, proline, serine, taurine, threonine, tryptophan, tyrosine and valine.

[0416] It may be preferable for the amino acids to be basic amino acids comprising an additional amine function optionally included in a ring or in a ureido function.

[0417] Such basic amino acids may preferably be chosen from those corresponding to formula (B) below:

[0418] in which

[0419] R of formula (IV) represents a group chosen from:

[0420] -(CH2)3-NH2,

[0421] -(CH2)2-NH2,

[0422] -(CH2)2-NH-CO-NH2, and

[0423] Compounds corresponding to formula (B) include the following: histidine, lysine, arginine, ornithine and citrulline.

[0424] The organic alkalizing agent may be chosen from among the heterocyclic organic amines. In addition to histidine, which has already been mentioned among the amino acids, pyridine, piperidine, imidazole, triazole, tetrazole, and benzimidazole may be mentioned in particular.

[0425] The organic alkalizing agent can also be chosen from amino acid dipeptides. Examples of amino acid dipeptides that can be used in the present invention include carnosine, anserine, and balein.

[0426] The organic alkalizing agent can also be chosen from compounds comprising a guanidine function. As amines of this type that can be used in the present invention, besides arginine, which has already been mentioned as an amino acid, creatine, creatinine, 1,1-dimethylguanidine, 1,1-diethylguanidine, glycocyamine, metformin, agmatine, N-amidinoalanine, 3-guanidinopropionic acid, 4-guanidinobutyric acid and 2-([amino(imino)met hyl]aminojethane-1 -sulfonic acid.

[0427] In a preferred embodiment of the present invention, the organic alkalizing agent may be selected from amino acids, preferably basic amino acids, and more preferably, arginine, lysine, histidine, or mixtures thereof. Even more preferably, the organic alkalizing agent may be arginine.

[0428] Hybrid compounds that may be mentioned include salts of the amines mentioned above with acids such as carbonic acid or hydrochloric acid. Guanidine carbonate or monoethanolamine hydrochloride may be used in particular.

[0429] In some embodiments, the amount of the pH correcting agent in the composition 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.

[0430] In some embodiments, the quantities of the pH correcting agent in the composition 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.

[0431] In some embodiments, the pH correcting agent may be present in an amount ranging from 0.01% to 15% by weight, preferably from 0.05% to 10% by weight, and more preferably from 0.1% to 5% by weight or less, relative to the total weight of the composition.

[0432] It is preferable that the composition according to the present invention has a pH of 4.5 or more, and more preferably of 5 or more.

[0433] It is preferable that the composition according to the present invention has a pH of 6.5 or less, and more preferably of 6 or less.

[0434] It is preferable that the composition according to the present invention has a pH of 4.5 to 6.5, and more preferably of 5 to 6.

[0435] The pH of the composition means the pH of the aqueous phase of the composition according to the present invention.

[0436] It may be preferable that at least one buffer or buffering agent also be used, as a pH correcting agent, in combination with the acidifying agent and / or the alkalizing agent, in order to stabilize the pH of the composition according to the present invention.

[0437] Any commonly known buffer may be used. For example, salts of acids or bases, preferably salts of weak acids or weak bases, may be used. For example, sodium citrate or sodium lactate may be used as a buffer if citric acid or lactic acid is used as the acidifying agent. Medium / solvent

[0438] The composition according to an embodiment of the present invention may advantageously comprise at least one medium / solvent, including water and / or an organic medium / solvent.

[0439] In some embodiments, the composition may comprise water in varying amounts. For low-viscosity applications of the composition, for example as a leave-on lotion, a relatively large amount of water may be used. For example, water is used at a content greater than or equal to 20% by weight relative to the total weight of the composition. The water content in the low-viscosity composition according to the invention preferably ranges from 20% to 99% by weight, or preferably from 30% to 95% by weight, or from 40% to 90% by weight, relative to the total weight of the composition. For high-viscosity applications of the composition, for example as a leave-on cream, a relatively smaller amount of water may be used. The high-viscosity composition according to the invention advantageously comprises water at a content less than or equal to 40% by weight relative to the total weight of the composition.

[0440] In some embodiments, the amount of water in the composition may be 20% by weight or more, preferably 30% by weight or more, and more preferably 40% by weight or more, relative to the total weight of the composition.

[0441] In some embodiments, the amount of water in the composition 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.

[0442] It may be preferable that the quantity of water in the composition according to the present invention be from 20% to 99% by weight, preferably from 30% to 95% by weight and, more preferably, from 40% to 90% by weight, relative to the total weight of the composition.

[0443] The composition according to the invention may also comprise one or more organic media / solvents, preferably soluble organic media / solvents in water (solubility greater than or equal to 5% in water at 25°C and atmospheric pressure).

[0444] Examples of organic media / solvents that may be cited include 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, a 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.

[0445] The organic media / solvents, if any, are present in an amount ranging from 0.1% to 40% by weight, preferably from 1% to 30% by weight, or from 5% to 20% by weight, relative to the total weight of the composition according to the invention.

[0446] The composition according to the present invention may then include other additives, active agents, carriers, adjuvants which are known in the art as compatible with keratinous material and are cosmetically acceptable.

[0447] The composition according to the present invention lightens or depigments a keratinous material, preferably the skin.

[0448] The composition according to the present invention may be useful for treating keratinous material, preferably skin, to confer a whitening or depigmenting effect. Preparation of the composition

[0449] The present invention, according to one embodiment, provides a method for preparing the composition. The compositions according to the invention can be manufactured by known processes, generally used in the cosmetic or dermatological field.

[0450] The process comprises mixing the essential and optional components described above by any known method. In one embodiment, the composition of the present invention can be prepared by a process including the steps of mixing at least one compound of formula (I) or (1'), at least one reducing agent, and an amino acid with water or any suitable solvent. The mixing includes, if necessary, the addition of other additives. The process involves mixing the components at any temperature, preferably at room temperature, more preferably at 30°C or above, at 40°C or above, and more preferably at 50°C or above.

[0451] The composition of the according to the present invention may be in various forms, but not limited to, an emulsion, a solution, a gel or a cream. Method / Use of the composition

[0452] The present invention according to one embodiment proposes a cosmetic process for treating keratinous material, the process comprising: the application of the composition of the present invention to the keratinous material, preferably to the skin.

[0453] In certain embodiments, the present invention proposes a non-therapeutic cosmetic process for treating keratinous material, the process comprising: the application of the composition of the present invention to the keratinous material, preferably to the skin.

[0454] The present invention, according to one embodiment, proposes using the composition to lighten or depigment keratinous material, preferably skin. In some embodiments, the composition is suitable for treating darker and / or more pigmented spots on the skin. In some embodiments, the composition is useful for providing necessary skin care, preferably for lightening the skin and / or reducing or lightening darker and / or more pigmented spots on the skin.

[0455] The present invention, according to one embodiment, provides a cosmetic composition that can be applied once a day, twice a day, or more than once or more than twice a day. In some cases, the composition is applied in the evening before bedtime. In other cases, the compositions are applied in the morning. In still other cases, the composition can be applied immediately after washing the skin. The compositions can be used once, or for a series of days, weeks, or months. For example, the compositions can be used daily for a period of 1, 2, 3, 4, 5, 6, 7, 8 weeks or more, or months.

[0456] The present invention, according to one embodiment, proposes the use of the combination of:

[0457] (I) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates

[0458] in which

[0459] X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen;

[0460] m is equal to 0 or 1;

[0461] M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium;

[0462] R represents a group chosen from:

[0463] i) -OH,

[0464] H) -O-M'+ with M'+ as defined previously for M+,

[0465] iii) o (HD OY

[0466] in which,

[0467] • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2;

[0468] • m' is equal to 0 or 1, preferably 1;

[0469] • X' is such as defined for X, preferably X' represents an oxygen atom; and

[0470] • M' '+ is such as defined previously for M+, and M+, M'+, M”+ are identical or different, preferably identical and

[0471] (II) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates Ra RC JL H l Rb

[0472] in which

[0473] Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen;

[0474] Ra and Rc independently represent one of the following elements: 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 identical or different, chosen from: i. a hydroxy; ii. carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii. a Guanidino group; iv. an alkyl -S-(C1-C12) and v. an optionally substituted C3-C8 heterocyclyl,

[0475] and

[0476] c) -C(O)-R d, in which Rd is selected from an aminoalkyl in (C1-C12), an alkyl in (C1-C12), an alkoxy in (C1-C12);

[0477] or

[0478] Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms;

[0479] and

[0480] R b represents one of the following: a. a hydrogen atom; b. a saturated hydrocarbon group linear in C1-C12 or branched in C3-C12 or cyclic in C3-C8>

[0481] in a composition comprising at least one compound selected from the compounds of formula (I), its tautomer of formula (P), their salts, optical isomers, racemates, solvates, hydrates or mixtures thereof: (D (D

[0482] formulas (I) and (I') in which:

[0483] R 1 designates a radical chosen from:

[0484] a) a hydrogen atom;

[0485] b) a linear saturated alkyl group in C1-C10 or branched in C3-C10 optionally substituted by one or more groups, which may be identical or different, selected from:

[0486] i) -O-R3;

[0487] ii) -S-R3;

[0488] R 2 denotes a radical chosen from:

[0489] a) a hydrogen atom;

[0490] 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 identical or different, selected from:

[0491] i) -O-R3;

[0492] ii) -S-R3;

[0493] iii) -C(O)-O-R3 ;

[0494] iv) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyls and / or by one or more alkoxy radicals in CrC8;

[0495] c) an aryl group in C5-Ci2, optionally substituted by one or more hydroxyl groups and / or by one or more CrC8 alkoxy radicals; and

[0496] R 3 designates a radical chosen from:

[0497] a) a hydrogen atom;

[0498] b) a linear saturated alkyl group in the C1-C10 or branched in the C3-C10, for stabilizing the compound of formula (I), its tautomer of formula (I'), its salts, solvates, hydrates, optical isomers, racemates or mixtures thereof, in the composition. The term "stabilize" has the same meaning as enhance stability.

[0499] According to one embodiment of the invention, the composition comprises an aqueous phase. The composition is in particular formulated as water-in-oil or oil-in-water emulsions or as multiple emulsions (triple oil-in-water-in-oil or water-in-oil-in-water emulsions (such emulsions are known and described, for example, by C. Fox in "Cosmetics and Toiletries" - November 1986 - Vol. 101 - pages 101-112)).

[0500] According to a particular embodiment of the invention, the composition is a direct emulsion, that is to say, an oil-in-water or O / W emulsion. EXAMPLES

[0501] The disclosure will now be illustrated by practical examples, which are intended to demonstrate how the disclosure works and are not intended to impose restrictive limitations on the scope of this disclosure. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as that commonly understood by a person skilled in the art of this disclosure. Although processes and materials similar or equivalent to those described herein may be used in the practice of the disclosed processes and compositions, examples of processes, devices, and materials are described herein. It should be understood that this disclosure is not limited to any particular composition, processes, and experimental conditions described, to the extent that such processes and conditions may be applicable.The present invention will be described in more detail by means of examples. However, these examples should not be interpreted as limiting the scope of the present invention. Example 1: Synthesis of compound 20

[0502] Compound 20 is synthesized as disclosed in Example 2 of patent EP3 390 363. Example 2: Cosmetic compositions

[0503] Composition A (according to the invention) was prepared from the ingredients described in Table 1 below. 0.50% by weight of Compound 20 of Formula (I), i.e., 2-mercaptonicotinoyl glycine, 0.05% by weight of sodium thiosulfate, 1.00% by weight of serine, a total of 6.00% by weight of glyceryl stearate, PEG-100 stearate, and PEG-40 stearate, 2.40% by weight of fatty alcohols, 16.00% by weight of hydrogenated polyisobutene, 1.20% by weight of preservatives, 0.20% by weight of chelating agent, 18.00% by weight of isohexadecane, 0.36% by weight of thickening agent, and 0.36% by weight of triethanolamine, as well as a sufficient quantity of water to obtain Composition A1. Similarly, compositions A2 to A5 (according to the invention) were prepared with 1% by weight each of methionine, proline, aspartic acid and glycine respectively.The comparative composition B without amino acids was also prepared in a similar manner, including the ingredients as mentioned in Table 1 below.

[0504] [Tables 1] Composition / Ingredients / INCI (% by weight) Al A2 A3 A4 A5 B Compound 20 of formula (I) 2-Mercaptonicotinyl Glycine 0.50 0.50 0.50 0.50 0.50 0.50 Reducing Agent Sodium Thiosulfate 0.05 0.05 0.05 0.05 0.05 0.05 Amino Acid Serine 1.00 0.00 0.00 0.00 0.00 0.00 Methionine 0.00 1.00 0.00 0.00 0.00 0.00 Proline 0.00 0.00 1.00 0.00 0.00 0.00 Aspartic Acid 0.00 0.00 0.00 1.00 0.00 0.00 Glycine 0.00 0.00 0.00 0.00 1.00 0.00 Glyceryl Stearate (and) PEG-100 Stearate 3.00 3.00 3.00 3.00 3.00 3.00 PEG-40 Stearate 3.00 3.00 3.00 3.00 3.00 3.00 Fatty Alcohols 2.40 2.40 2.40 2.40 2.40 2.40 Hydrogenated Polyisobutene 6.00 6.00 6.00 6.00 6.00 6.00 6.00 Preservatives 1.20 1.20 1.20 1.20 1.20 1.20 Chelating Agent 0.20 0.20 0.20 0.20 0.20 0.20 Isohexadecane 18.00 18.00 18.00 18.00 18.00 18.00 Thickening Agent 0.36 0.36 0.36 0.36 0.36 0.36 Triethanolamine 0.36 0.36 0.36 0.36 0.36 0.36 Water (Water) / Aqua Qs 10 0 Qs 10 0 Qs 10 0 Qs 10 0 Qs 10 0 Qs 10 0 Example 3 Composition stability

[0505] The compositions as prepared in Example 1 were analyzed to determine their stability when stored at different temperatures.

[0506] Approximately 1.0 g of each composition was independently 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 subjected to sonication followed by stirring for approximately 1.5 hours. The resulting solution was filtered. A portion of the filtered solution was subjected to HPLC-UPLC analysis to determine the amount of compound 20 (2-Mercaptonicotinoyl Glycine) at time T0. Another portion of the filtered solution was placed in an oven at 45°C for a period of 2 months, and the presence of compound 20 at accelerated aging T2M at 45°C was determined. Another portion of the filtered solution was stored at room temperature for 2 months, and the presence of compound 20 in the T2M solution at TA was determined.

[0507]

[0508] The details of the HPLC-UV assays are as follows: [Table 2] Apparatus / Reagents

[0509] HPLC System Ultra-performance liquid chromatography (UPLC) HPLC column RP18, 1.7, 2.1 mm x 100 mm Eluent A 0.1% phosphoric acid Eluent B Methanol

[0510] [Table 3] HPLC conditions UV detector 296 nm Column temp. 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

[0512] The quantity of compound 20 of formula (I) in each of the solutions was determined and the % values ​​of compound 20 of formula (I) measured are presented in Table 2.

[0513] [Tables4] Composition Compound 20 of formula (I) remaining (% by weight) T2M at TA T2M at 45°C Al (invention) 100 98 A2 (invention) 97.9 97.9 A3 (invention) 96 98 A4 (invention) 96 98 A5 (invention) 100 95.8 B (comparative) 96 94.6

[0514] It was found that compositions A1 to A5, comprising respectively an amino acid such as serine, methionine, proline, aspartic acid, and glycine, retained approximately 96% by weight of the compound thiopyridinione 20 of formula (I) when stored at room temperature for 2 months and approximately 95% by weight of the compound thiopyridinione 20 of formula (I) when stored under accelerated conditions at 45°C for 2 months. Thus, in the composition according to the present invention, the stability of the compound thiopyridinione 20 of formula (I) is increased compared to the comparative composition B without an amino acid. Therefore, the composition according to the present invention, comprising an amino acid with a reducing agent, provided a stable composition with an extended shelf life.

Claims

1. Demands Composition, preferably a cosmetic composition, comprising: (I) at least one compound selected from a compound of formula (I) below, its tautomer of formula (F) below, their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof: Formula (I) Formula (F) in which R i of formula (I) and (F) represents a radical chosen from: a) a hydrogen atom; b) a linear saturated alkyl group in the C1-C6 range or a branched C3-C6 range optionally substituted by one or more groups, which may be identical or different, chosen from: i) -O-R3 ii) -S-R3; preferably optionally substituted by one or more groups i) R 2 of formula (I) and (F) represents a radical chosen from: a) a hydrogen atom; b) a linear or branched saturated hydrocarbon group in C3-C1 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; ü) -SR3; iii) -C(O)-O-R3 ; (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; preferably substituted by one or more groups chosen from i) and iii), preferably iii) such as carboxy; R 3 of formula (I) and (F) represents a radical chosen from: a) a hydrogen atom; b) a linear saturated alkyl group in C1-C6 or branched in C3-C6; (II) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates O (II) WWW g WWW Q| ” ' rL in which X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen; m is equal to 0 or 1; M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal, or ammonium, more preferably chosen from an alkali metal such as sodium or potassium; Run group chosen from: i) -OH, ii) -O-M'+ with M'+ as defined previously for M+, iii) o in which, • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2; • m' is equal to 0 or 1, preferably 1; • X' is such that defined for X, preferably X' represents an oxygen atom; and • M”+ is such as defined previously for M+, and M+, M'+, M”+ are identical or different, preferably identical; And (III) at least one amino acid preferably of formula (III), its enantiomers, salts or solvates such as hydrates

2. in which Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen; Ra and Rc independently represent one of the following: a) a hydrogen atom; b) a linear saturated hydrocarbon group in C1-C1 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) a hydroxy; ii) carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii) a Guanidino group; (iv) an alkyl -S-(Ci-Ci2) and (v) an optionally substituted C3-C8 heterocyclyl, and c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (Cr C12), an alkyl in (C1-C12), an alkoxy in (C1-C12); Or Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms; And R b represents one of the following: i) a hydrogen atom; ii) a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 or cyclic in C3-C8. Composition according to claim 1, wherein (1) compound is selected from compounds 1 to 24, their tautomers, salts, solvates, hydrates, optical isomers, racemates or mixtures thereof, 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: K* Structure Nom chWqüe<A'.> : ? ï K "'■■■fi-'-' H N-ê&syta-thioxa- 2 N-mé^yt-2 <isxo- f î h^adyS-2-Brôço- 4 N-benzy93-feis>:o- 1.2^ÿ^pw;jï <Sie-3-ea^<»Œm{te 5 y. N-p^é^yl-2-tfiÎQKS- t'2^y<&opyrâtëne?3^cæ^ 6 y; N-cydstexy92-&iaxü- 1.2^ÿdtopÿïW»^3-eætK!(^^ 7 •■• ‘\x N42-'i4-méttayph^yl;gth^}-2-ta> :D-1,2-3years <topyfi^ 3-cafbcKarâte ÎS bH2-ffiéffiyîpro$ŸÏ^ V^ytâopy&&ie-3-ca&ox^ 9 N-pertyj-24hiaxe- l,2^ÿ<fropyfic&^3-«ajfc0K3^^ JO Vy'-'— .■N-nonÿ^-Z-^faxo i^-^JWy^ns^-cartMwra^ 11 ' y "" y> hy / x V : OH N-(2-hytiRwéWt>24ftj^^ 1;24l^{l.V-z-xÀ^dme-3 y '■$: yyy ï$ N, 2-me;ca^cmc<^namk{e 13 r XI.......k.....« yy % H 2r8tao-î, 2-cW& 3-caïboxaraide 14 T "1 ■'Ss N-(2.3<W^ rwPWÿ^^hsoxc- 1 ;2-dshy îftopy^ 15 rx y .■ ■ Jx. .y y-'" xy N41 > ®y<$roxypîe^ 2-îœo- f. 2-(âhydropyfl <Sne- 3-caffeoKamsde 16 CH ; ji 1, .. , y y "X ) Mi24hkKS-12-^ihydropy^ 3-yl k-ato^ 17 0 I ^H(2-thiû> '<^12-dhy^^ 18 ... 1..„.... ; y- Y VAV' "'XA « ? 1,2-^ydropyrâmr3-yi) cæbwS&W^ : .•^ .A :>V X-. v / A: ■■ v^yy - . y - x., •■ Xs. •• XN ■ '■ ' X< N4(2®î«»c<3-1,2-dBiÿ*opyf»dm-ly^ 20 ? H 11 s >b- cafbcnyÊ]giiyŒe 21 A ai N-wB^(2-tâ <w-1 j^hy sîropyï^n-3^) rartmshy^cèrfe (" •s:-:^        a         ,x.         ,.'x y n ■smsp-hysfoxyésylbs-» 1 2<®yî^opyfwi&-3’£afbox3^^ N-buib / t2-§thioxy3-1,2- d^ÿ^pyrafee-3-caitM)xam? <te

3.

4.

5. Composition according to any one of the preceding claims, wherein: - the compound of formula (I) or its tautomer of formula (!'), its salts, solvates, hydrates, optical isomers, racemates, or mixtures thereof, is in an amount ranging from 0.01% to 10% by weight, preferably from 0.05% to 5% by weight and, more preferably, from 0.1% to 3% by weight, relative to the total weight of the composition; - wherein the reducing agent is present in an amount ranging from 0.01% to 2% by weight, preferably from 0.02% to 1.0% by weight and, more preferably, from 0.03% to 0.5% by weight, relative to the total weight of the composition; and - the amino acid is present in an amount ranging from 0.01% to 10% by weight, preferably from 0.1% to 8.0% by weight and, more preferably, from 0.2% to 6% by weight, relative to the total weight of the composition. Composition according to any one of the preceding claims, wherein: X of formula (II) represents sulfur; m of formula (II) is equal to 1; M + of formula (II) is sodium or potassium; R of formula (II) represents a group chosen from i) -OH and ii) -O-M'+, with M'+, M+ and M'+ identical. Composition according to any one of the preceding claims, wherein the reducing agent is selected from sodium bisulfite, sodium metabisulfite, sodium sulfite, sodium thiosulfate or sodium sulfate.

6. Composition according to any one of the preceding claims, wherein: R a of formula (III) represents one of the following: a) a hydrogen atom; b) a linear saturated CrCi2 group optionally substituted by one or more groups, which may be identical or different, selected from: i) a hydroxyl group; ii) carboxylated or carboxylate salts, in particular of alkali metal, or alkaline earth metal, preferably of sodium or potassium; and ii) alkyl -S-(C1-C12); R c of formula (III) represents a hydrogen atom; or R a and R c of formula (III) being combined together to form a heterocyclyl ring having 3 to 8 atoms; and R b of formula (III) represents a hydrogen atom.

7. Composition according to any one of the preceding claims, wherein the amino acid is selected from a) serine, b) methionine, c) proline, d) aspartic acid, e) glycine, their enantiomers, their salts and their solvates such as their hydrates or combinations.

8. Cosmetic process for treating keratinous material, the process comprising: applying the composition according to any one of claims 1 to 7 to the keratinous material, preferably the skin.

9. Use of the composition according to any one of claims 1 to 7 for lightening or depigmenting keratinous material, preferably skin.

10. Use of a combination of (I) at least one reducing agent of formula (II), its mesomeric forms and its solvates such as hydrates o (II) R---S--CT M + [X]m in which X represents a heteroatom chosen from oxygen or sulfur, preferably oxygen; m is equal to 0 or 1; M+ is a cation, preferably chosen from an alkali metal, an alkaline earth metal or ammonium, more preferably chosen from an alkali metal such as sodium or potassium; R represents a group chosen from: i) -OH, ii) -O-M'+ with M'+ as defined previously for M+, in which • p is an inclusive integer chosen between 0 and 4, preferably 0, 1, 2 and more preferably 0 or 2; • m' is equal to 0 or 1, preferably 1; • X' is such that defined for X, preferably X' represents an oxygen atom; and • M”+ is such as defined previously for M+, and M+, M'+, M”+ are identical or different, preferably identical and (II) at least one amino acid of formula (III), its enantiomers, salts or solvates such as hydrates in which Y is chosen from hydrogen, an alkali metal or an alkaline earth metal, preferably hydrogen; Ra and Rc independently represent one of the following: 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 several groups, which may be identical or different, chosen from: i) a hydroxy; ii) carboxylated or carboxylate salts, in particular of alkali metal, or of alkaline earth metal, preferably of sodium or potassium; iii) a Guanidino group; iv) an alkyl -S-(C1-C12) and (v) an optionally substituted C3-C8 heterocyclyl, and c) -C(O)-R d, in which Rd is chosen from an aminoalkyl in (Cr Ci2), an alkyl in (C1-C12), an alkoxy in (C1-C12); Or Ra and Rc being combined together to form a heterocyclyl ring having 3 to 8 atoms; And R b represents one of the following: i) a hydrogen atom; ii) a linear saturated hydrocarbon group in C1-C12 or branched in C3-C12 OR cyclic in C3-C8, in a composition comprising at least one compound selected from the compounds of formula (I), its tautomer of formula (I1), salts, optical isomers, racemates, solvates, hydrates or mixtures thereof: (D (D formulas (I) and (I') in which: R 1 designates a radical chosen from: a) a hydrogen atom; b) a linear saturated alkyl group in C1-C10 or branched in C3-C10 optionally substituted by one or more groups, which may be identical or different, chosen from: i) -O-R3 ü)-S-R3 ; R 2 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 identical or different, chosen from: i) -O-R3; ii) -S-R3; iii) -C(O)-O-R3 ; (iv) 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; (c) an aryl group in the C5-Ci2 range, optionally substituted by one or more hydroxyl groups and / or by one or more alkoxy radicals in the Ci-C8 range; and R 3 designates a radical chosen from: a) a hydrogen atom; b) a linear saturated alkyl group in Ci-Cio or branched in C3-Cio, to stabilize the compound of formula (I), its tautomer of formula (P), their salts, solvates, hydrates, optical isomers, racemates or mixtures thereof, in the composition.