Compositions for delivery of active compounds

Abstract

The present invention relates to a composition comprising A) a thiopyridone compound; b) a C12-20 fatty compound having at most one C = C bond, preferably a C12-C18 fatty compound, or preferably a C12-C16 fatty compound.

Description

Technical Field

[0001] The present invention relates to a composition for enhancing the delivery of an active compound into the skin. Background of the Invention

[0003] Skin care, such as brightening skin tone, has always been of great concern to consumers. Therefore, delivering highly effective products with skin benefits such as hydration, moisturizing, brightening, cleansing, etc. to consumers has always been the ultimate goal in the cosmetics field.

[0004] In order to effectively deliver, various forms of products are used. To date, hydrophilic active substances are sometimes still difficult to deliver to the deep skin (around the dermal junction). In particular, it is known that certain thiopyridone compounds also show good depigmentation activity even at low concentrations, see, for example, WO2012080075 and WO2017 / 102349. Thiopyridone compounds can show strong depigmentation or brightening effects by reducing the production of melanin.

[0005] Therefore, there is a need for a composition for enhancing the delivery of active compounds, such as thiopyridone compounds, into the skin. Summary of the invention

[0006] The inventors have unexpectedly found that a composition comprising the following components can meet the requirements: A) a compound of formula (I) or (I'), which can be considered as a thiopyridone compound, or their salts, their optical isomers, racemates and / or solvates such as hydrates, alone or as a mixture; B) a C12-20 fatty compound having at most one C=C bond.

[0007]

[0008] In formula (I) and (I'):

[0009] R1 represents a group selected from the following:

[0010] a) Hydrogen atom;

[0011] b) Saturated straight chain C1-C 10 or branched C3-C 10 Alkyl, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0012] i)-O-R3

[0013] ii) -S-R3;

[0014] R2 represents a group selected from the following:

[0015] a) Hydrogen atom;

[0016] b) Saturated straight chain C1-C 12 or branched C3-C 12 or a cyclic C3-C8 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0017] i)-O-R3

[0018] ii)-S-R3

[0019] iii) -C(O)-O-R3;

[0020] iv) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups;

[0021] c) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-

[0022] C8 alkoxy substitution

[0023] R3 represents a group selected from the following:

[0024] a) Hydrogen atom;

[0025] b) Saturated straight chain C1-C 10 or branched C3-C 10 alkyl;

[0026] When a tautomeric equilibrium exists according to the following scheme, compound (I') is a tautomeric form of compound (I):

[0027]

[0028] According to one embodiment of the invention, R1 represents a hydrogen atom.

[0029] According to another embodiment of the present invention, R1 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight chain (C1-C6)alkyl or branched chain (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably ethyl. In particular, the alkyl of R1 is unsubstituted.

[0030] According to one embodiment of the invention, R2 represents a hydrogen atom.

[0031] According to another embodiment of the present invention, R2 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10)alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; the alkyl of R2 is unsubstituted.

[0032] According to another embodiment of the present invention, R2 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; said alkyl is substituted by one or more groups selected from i), ii), iii) and iv) as defined above. Preferably, said alkyl is substituted by one or two groups selected from i), ii) and iii), more preferably by one or two groups selected from i) and iii), more preferably by a group iii) which is a carboxyl group.

[0033] A further variant of the radical R2 consists in that the alkyl radical is substituted by a radical iv), in particular by a phenyl radical.

[0034] According to another embodiment of the present invention, R2 represents (C3-C8)cycloalkyl, preferably (C5-C7)cycloalkyl, such as cyclohexyl.

[0035] According to another embodiment of the present invention, R2 represents C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8alkoxy groups, preferably represents phenyl, which is in particular unsubstituted.

[0036] According to one embodiment, R3 represents a hydrogen atom.

[0037] According to another embodiment, R3 represents a saturated straight-chain C1-C 10 or branched C3-C 10 Alkyl; in particular straight chain (C1-C6) alkyl or branched chain (C3-C6) alkyl, preferably (C1-C4) alkyl such as methyl. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The distribution of compound 20 in the test samples of Example 1 and other examples is shown;

[0039] Figure 2 The distribution of TXA in the test samples of Example 2 and other examples is shown;

[0040] Figure 3 shows the distribution of Compound 20 in the test samples of Examples 10-11 and Comparative Example 3 obtained via Raman confocal microscopy; and

[0041] Figure 4 The distribution of TXA in the test samples of Examples 10-11 and Comparative Example 3 obtained via Raman confocal microscopy is shown.

[0042] Specific embodiments of the invention

[0043] Throughout the specification (including the claims), unless otherwise mentioned, the term "comprising one / kind" should be understood as being synonymous with "comprising at least one / kind". In addition, the expression "at least one / kind" used in this specification is equivalent to the expression "one / kind or more / kind".

[0044] For purposes of the present invention, and unless otherwise specified:

[0045] "Saturated straight chain C1-C 12 or branched C3-C 12 "Hydrocarbon group" is equivalent to "straight chain (C1-C 12 ) alkyl or branched (C3-C 12 ) alkyl", which corresponds to a saturated C1-C 12 Straight chain or C3-C 12 branched hydrocarbon groups, and preferably based on C1-C 10 Straight chain or C3-C 10 A branched hydrocarbon group, more preferably a group based on a C1-C6 straight chain or C3-C6 branched hydrocarbon; preferably, the straight chain or branched group can be selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl and decyl.

[0046] More preferably, the saturated straight or branched alkyl group can be selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, pentyl, hexyl, heptyl and octyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl.

[0047] ■Saturated hydrocarbon cyclic C3-C8 groups are monocyclic or bicyclic cycloalkyl groups containing 3 to 8 carbon atoms, especially monocyclic cycloalkyl groups in C5 to C7, such as cyclohexyl,

[0048] ■ "Alkoxy" is an alkyloxy group, wherein the alkyl group is based on a straight or branched C1-C 16 And preferably a C1-C8 hydrocarbon group;

[0049] ■When alkoxy is optionally substituted, this means that alkyl is optionally substituted as defined above;

[0050] ■ "Aryl" represents a fused or non-fused monocyclic or bicyclic carbon-based group containing 5 to 12 carbon atoms, preferably 6 to 10 carbon atoms, and wherein at least one ring is aromatic; preferably, aryl is phenyl, biphenyl, naphthyl, more preferably phenyl;

[0051] ■ The term "at least one" is equivalent to the term "one or more"; and

[0052] ■ The term "inclusive" used for concentration ranges means that the limits of the range are included in the defined range.

[0053] Salts of compounds of formula (I), (I'), (II) or (II') as defined below include conventional non-toxic salts of said compounds, such as those formed from organic or inorganic acids or from organic or inorganic bases.

[0054] As salts of the compounds of formula (I), (I'), (II) or (II'), mention may be made of:

[0055] A salt obtained by adding a compound of formula (I) or (II) to:

[0056] - inorganic bases, such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonium hydroxide, magnesium hydroxide, lithium hydroxide, and carbonates or bicarbonates of sodium, potassium or calcium;

[0057] or

[0058] - organic bases, such as primary, secondary or tertiary alkylamines, for example triethylamine or butylamine. The primary, secondary or tertiary alkylamines may contain one or more nitrogen and / or oxygen atoms and may thus contain, for example, one or more alcohol functions; mention may be made in particular of 2-amino-2-methylpropanol, ethanolamine, triethanolamine, 2-dimethylaminopropanol, 2-amino-2-(hydroxymethyl)-1,3-propanediol and 3-(dimethylamino)propylamine.

[0059] Mention may also be made of the salts of amino acids such as lysine, arginine, guanidine, glutamic acid and aspartic acid. Advantageously, the salts of the compounds of formula (I) or (II) when they contain a carboxyl group may be chosen from alkali metal or alkaline earth metal salts, such as sodium, potassium, calcium or magnesium salts, and ammonium salts.

[0060] ■ "Organic or inorganic acid salt" is more particularly selected from salts 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 tolyloxysulfinic acid and phenoxysulfinic acid; xii) phosphoric acid H3PO4; xiii) acetic acid CH3C(O)OH; xiv) trifluoromethanesulfonic acid CF3SO3H; and xv) tetrafluoroboric acid HBF4;

[0061] ■Acceptable solvates of the compounds described in the present invention include conventional solvates, such as those formed due to the presence of solvents during the preparation of the compounds. As examples, solvates formed due to the presence of water or linear or branched alcohols such as ethanol or isopropanol may be mentioned.

[0062] ■Optical isomers, especially enantiomers and diastereomers.

[0063] Preferably, the "keratin material" according to the invention is the skin. "Skin" means all body skin. Still more preferably, the keratin material is the face or neck, especially the face.

[0064] In the present application, unless otherwise specifically mentioned, the amount, content, part and percentage are expressed on a weight basis.

[0065] In the present application, when necessary, numerical range is defined with lower limit and upper limit, such as one or more lower limits and one or more upper limits are given to form a range, which is optionally together with one or more preferred ranges. A given range can be defined by selecting the lower limit and upper limit of the boundary that defines a given range. All ranges defined in this way are end-point-containing and combinable, i.e., any lower limit can be combined with any upper limit to form a range, as long as lower limit and upper limit are provided to modify the same subject. For example, when listing the scope of 60-110 and 80-120 for a specific subject, it should be understood that scope 60-120 and 80-110 are also considered and covered. In addition, if the lower limit listed is 1 and 2, and the upper limit is 3,4 and 5, then the following range is all predictable and within the scope of the present disclosure: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5.

[0066] Except in the operating examples, or where otherwise indicated, all numbers expressing amounts of ingredients and / or reaction conditions are to be understood as being modified in all instances by the term "about," having the conventional meaning known in the art, such as within 10% of the indicated number (e.g., "about 10%" means 9%-11%, and "about 2%" means 1.8%-2.2%).

[0067] Component A)

[0068] As component A), the composition according to the invention comprises the compound of the following formula (I) or (I') or the following tautomer (I') or their salts, their optical isomers, racemates and / or their solvates such as hydrates, alone or as a mixture:

[0069]

[0070] In formula (I) and (I'):

[0071] R1 represents a group selected from the following:

[0072] a) Hydrogen atom;

[0073] b) Saturated straight chain C1-C 10 or branched C3-C 10 Alkyl, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0074] i)-O-R3

[0075] ii) -S-R3;

[0076] R2 represents a group selected from the following:

[0077] a) Hydrogen atom;

[0078] b) Saturated straight chain C1-C 12 or branched C3-C 12 or a cyclic C3-C8 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0079] i)-O-R3

[0080] ii)-S-R3

[0081] iii) -C(O)-O-R3;

[0082] iv) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups;

[0083] c) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups

[0084] R3 represents a group selected from the following:

[0085] a) Hydrogen atom;

[0086] b) Saturated straight chain C1-C 10 or branched C3-C 10 alkyl;

[0087] When a tautomeric equilibrium exists according to the following scheme, compound (I') is a tautomeric form of compound (I):

[0088]

[0089] According to one embodiment of the invention, R1 represents a hydrogen atom.

[0090] According to another embodiment of the present invention, R1 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight chain (C1-C6)alkyl or branched chain (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably ethyl. In particular, the alkyl of R1 is unsubstituted.

[0091] According to one embodiment of the invention, R2 represents a hydrogen atom.

[0092] According to another embodiment of the present invention, R2 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; the alkyl of R2 is unsubstituted.

[0093] According to another embodiment of the present invention, R2 represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; said alkyl is substituted by one or more groups selected from i), ii), iii) and iv) as defined above. Preferably, said alkyl is substituted by one or two groups selected from i), ii) and iii), more preferably by one or two groups selected from i) and iii), more preferably by a group iii) which is a carboxyl group.

[0094] A further variant of the radical R2 consists in that the alkyl radical is substituted by a radical iv), in particular by a phenyl radical.

[0095] According to another embodiment of the present invention, R2 represents (C3-C8)cycloalkyl, preferably (C5-C7)cycloalkyl, such as cyclohexyl.

[0096] According to another embodiment of the present invention, R2 represents a C5-C8 alkoxy group optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups. 12 Aryl, preferably phenyl, is in particular unsubstituted.

[0097] According to one embodiment, R3 represents a hydrogen atom.

[0098] According to another embodiment, R3 represents a saturated straight-chain C1-C 10 or branched C3-C 10Alkyl; in particular straight chain (C1-C6) alkyl or branched chain (C3-C6) alkyl, preferably (C1-C4) alkyl such as methyl.

[0099] Preferably, the compound of formula (I) and the tautomer (I') or their salts, their optical isomers, racemates and / or their solvates such as hydrates, alone or as a mixture;

[0100] Has the following meanings:

[0101] R1 represents a group selected from the following:

[0102] a) Hydrogen atom;

[0103] b) a saturated straight-chain C1-C6 or branched C3-C6 alkyl group, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0104] i)-O-R3

[0105] ii) -S-R3;

[0106] Preferably, it is optionally substituted by one or more groups i)

[0107] R2 represents a group selected from the following:

[0108] a) Hydrogen atom;

[0109] b) Saturated straight chain C1-C 10 or branched C3-C 10 or a cyclic C3-C8 such as C5-C6 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0110] i)-O-R3

[0111] ii)-S-R3

[0112] iii) -C(O)-O-R3;

[0113] iv) phenyl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C4alkoxy groups such as methoxy;

[0114] Optionally substituted by one or more groups selected from i) and iii), preferably substituted by iii), such as carboxyl. R3 represents a group selected from the following:

[0115] a) Hydrogen atom;

[0116] b) Saturated straight chain C1-C6 or branched C3-C6 alkyl

[0117] Preferably, the compound of formula (I) and the tautomer (I') or their salts, their optical isomers, racemates and / or their solvates such as hydrates, alone or as a mixture;

[0118] Has the following meanings:

[0119] R1 represents a group selected from the following:

[0120] a) Hydrogen atom;

[0121] b) saturated straight-chain C1-C4 or branched C3-C4 alkyl, which is optionally substituted by one or more groups, which may be the same or different, selected from i) -OR3, more preferably unsubstituted;

[0122] R2 represents a group selected from the following:

[0123] a) Hydrogen atom;

[0124] b) Saturated straight chain C1-C 10 or branched C3-C 10 or a cyclic C3-C8 such as C5-C6 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from:

[0125] i)-O-R3

[0126] iii) -C(O)-O-R3;

[0127] iv) C5-C4 optionally substituted by one or more hydroxyl groups and / or by one or more C1-C4 alkoxy groups 12 Aryl;

[0128] R3 represents a group selected from the following:

[0129] a) Hydrogen atom;

[0130] b) Saturated straight-chain C1-C4 or branched C3-C4 alkyl groups, such as methyl or ethyl.

[0131] Preferably, the compound of formula (I) and the tautomer (I') or their salts, their optical isomers, racemates and / or their solvates such as hydrates, alone or as a mixture;

[0132] Has the following meanings:

[0133] R1 is a hydrogen atom; and

[0134] R2 represents a group selected from the following:

[0135] a) Hydrogen atom;

[0136] b) a saturated straight-chain C1-C5 or branched C3-C5 or cyclic C3-C8 such as C5-C6 hydrocarbon group, substituted by one or more groups, which may be the same or different, selected from v) -C(O)-O-R3, preferably substituted by one group iii) -C(O)-O-R3;

[0137] Even more preferably, R2 is a saturated straight-chain C1-C4 or branched C3-C4 hydrocarbon radical substituted by a group iii) -C(O)-O-R3.

[0138] According to another preferred embodiment, the compound of formula (I) and the tautomer (I') are selected from the compounds of formula (II) and their tautomers, their salts, their solvates and their optical isomers, and their racemates, alone or as a mixture:

[0139]

[0140] Formula (II) and (II'), wherein R1 and R3 have the same meanings as for the compounds of formula (I) and (I'), and X represents an alkylene group -(CH2) n -, wherein n is an integer from 1 to 10 (inclusive), preferably from 1 to 6, more preferably from 1 to 4, such as 1, preferably R3 represents a hydrogen atom.

[0141] Among the compounds of formula (I), preference is given to using the following compounds, as well as their tautomers or their salts, their optical isomers, racemates, and / or their solvates such as hydrates, alone or as a mixture:

[0142]

[0143]

[0144]

[0145]

[0146] Among these compounds, the following compounds are more particularly preferred:

[0147]

[0148]

[0149]

[0150]

[0151] More preferably, among these compounds, the following compounds are more particularly preferred:

[0152]

[0153]

[0154] Even more preferably, among these compounds, the following compounds are more particularly preferred:

[0155]

[0156] In a most preferred embodiment, the compound according to the invention is the following:

[0157]

[0158] All compounds can be obtained from commercially available reagents by chemical methods known to those skilled in the art. For example, the synthesis method disclosed in European Patent Application EP3390363 can be used.

[0159] Compound 20 (N-[(2-thione-1,2-dihydropyridin-3-yl)carbonyl]glycine), which may also be named 3-carboxymethylaminocarbonyl-2-thiopyridone, is a typical representative of the thiopyridone compounds useful according to the present invention.

[0160] Solubility of component A)

[0161] Through intensive research, the present inventors believe, without being bound by any known theory, that compounds of formula (I) or (I'), especially compound 20, may be typical representatives of useful thiopyridone compounds according to the present invention, mainly due to their specific log P.

[0162] The term "log P" is a measure known in the art to distinguish between "hydrophilic" and "hydrophobic" compounds. The value of log P can be determined by any conventional method known in the art. For "log P", P is the partition coefficient, which represents the ratio of the equilibrium concentration of the compound in the organic phase to its equilibrium concentration in the aqueous phase. Typically, the P value of the compound between octanol and water is used in the art. Thus, hydrophilic compounds typically have a log P value of less than 3.5, less than 1.0, or typically less than about -0.5, where P is the partition coefficient of the compound between octanol and water; and hydrophobic compounds typically have a log P of 3.5 or greater, or typically 5.0 or greater.

[0163] Based on compound 20, the present inventors conducted extensive studies and determined that compound 20 is particularly useful mainly because it has a log P falling within the range of -1.6 to 0.5, preferably -0.5 to 0.2. Therefore, the thiopyridone compound of formula (I) or (I') having a log P of -1.6 to 0.5 is particularly preferably used as component A).

[0164] Component A), e.g. compounds (I), (I'), (II) and / or (II'), especially compounds having a log P of -1.6 to 0.5, may be present in an amount of, e.g., 0.01 to 10 wt. %, preferably 0.1 to 5 wt. %, in particular 0.5 to 3 wt. %, relative to the total weight of the composition.

[0165] Component A'), additional hydrophilic active compound

[0166] As mentioned above, compound 20 is particularly useful primarily because it has a log P falling within the range of -1.6 to 0.5. In other words, various cosmetically acceptable additional hydrophilic active compounds that need to be delivered to the skin can be used as component A') according to the present invention or used in combination with component A); as long as the additional hydrophilic active compound has a log P of -1.6 to 0.5.

[0167] According to one embodiment of the present invention, component A') preferably carries a carboxyl group, in particular a carboxylic acid or an ester / salt thereof, preferably a carboxylic acid.

[0168] For example, among others, tranexamic acid (TXA) is a typical example of component A'). According to one embodiment of the present invention, TXA is used as component A'), together with compound 20 as component A).

[0169] In addition, water-soluble vitamins can be used as active compounds of component A') in the composition. Useful examples of vitamins include vitamin C (ascorbic acid), vitamin B group (e.g. vitamin B5 (panthenol), vitamin B3 (niacinamide), vitamin B1 and vitamin B2), niacin, folic acid, pantothenic acid, derivatives of these vitamins (particularly esters) and mixtures thereof.

[0170] Component A), ie the thiopyridone compound of formula (I) or (I'), is a derivative of nicotinamide. For the purposes of the present invention, other derivatives thereof known as active compounds for cosmetic use, in particular for application to the skin, can also be used.

[0171] Component A') having a log P of -1.6 to 0.5 may be present in an amount of, for example, 0.01 to 20 wt%, preferably 0.05 to 10 wt%, or preferably 0.1 to 5 wt%, relative to the total weight of the composition.

[0172] Component B), C12-20 fatty compounds having at most one C=C bond

[0173] The composition according to the invention may comprise C12-20 fatty compounds having at most one C=C double bond, ie having one C=C bond or having no C=C bonds, provided that when component B) is a fatty acid, it is a C12-C16 fatty acid.

[0174] The term "fatty compound" refers to an organic compound that is insoluble in water at normal temperature (25°C) and atmospheric pressure (760 mmHg) (solubility is less than 5%, preferably 1% and even more preferably 0.1%). In addition, the fatty compound is generally soluble in an organic solvent such as chloroform, ethanol, benzene or decamethylcyclopentasiloxane under the same temperature and pressure conditions.

[0175] The fatty compounds are especially selected from fatty alcohols, fatty acids, fatty acid esters and / or fatty alcohol esters. According to one embodiment of the invention, the fatty compounds of component B) according to the invention contain no additional heteroatoms besides C, H and O atoms.

[0176] According to the present invention, it is believed that the specific component B) is used in combination with component A) and / or A') to promote the delivery of component A) and / or A') to the skin. Without being limited by any known theory, it is inferred that a carbon chain of appropriate length is important for delivery. Too long a carbon chain can lead to a smaller delivery effect, while too short a carbon chain can be too volatile to be formulated into a usable product. By studying the matching with component A) and / or A') and through experiments, it is believed that the usable component B) can be a C12-20 fatty compound, preferably a C12-C18 fatty compound, or preferably a C12-C16 fatty compound.

[0177] According to one embodiment of the present invention, exemplary component B) may carry C1-C6 alkyl branches.

[0178] At the same time, it is surprising to see that, for the purposes of the present invention, useful fatty compounds may preferably have at most one C=C double bond, for example no C=C bond. Thus, C12-20 fatty compounds, preferably C12-C18 fatty compounds, or preferably C12-C16 fatty compounds having a saturated carbon chain may be particularly useful.

[0179] The fatty alcohols that can be used in the composition of the invention are not oxyalkylenated. They are saturated or unsaturated, linear or branched, and contain from 12 to 20 carbon atoms. Mention may be made of lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, oleyl alcohol and mixtures thereof (cetostearyl alcohol), octyldodecanol, butyloctanol or hexyldecanol.

[0180] Fatty acids useful in the compositions of the present invention include C12-C16 fatty acids, such as lauric or lauroleic acid (C12), myristic or myristoleic acid (C14), palmitic or palmitoleic acid (C16).

[0181] Usable esters are esters of saturated or unsaturated, linear or branched aliphatic monoacid or polyacid and saturated or unsaturated, linear or branched aliphatic monoalcohol or polyalcohol, as long as the total carbon number of the ester is 12 to 20.

[0182] Among the monoesters, mention may be made of cetyl lactate; C 12 -C 15 Alkyl esters; lauryl lactate; oleyl lactate; octyl octanoate; isononyl isononanoate; octyl isononanoate; 2-ethylhexyl isononanoate; octyl nonanoate; ethyl palmitate and isopropyl palmitate; alkyl myristates such as butyl myristate, myristate, laurate or ethyl oleate.

[0183] Among the polyesters, mention may be made of: diethyl sebacate; diisopropyl sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl maleate; glyceryl undecylenate; propylene glycol dicaprylate; triisopropyl citrate; glyceryl trilactate.

[0184] Preferably, no C18 or higher fatty acids are included in the composition of the present invention.

[0185] Advantageously, the content of fatty compound(s) ranges from 0.01% to 30% by weight, preferably from 0.1% to 10% by weight or from 0.5% to 5% by weight relative to the total weight of the composition.

[0186] Component C), surfactant

[0187] The composition according to the invention may comprise as optional component C) a surfactant, for example a nonionic surfactant or a mixture thereof. According to the invention, any conventional surfactant may be used, provided that it is compatible with the other components of the composition, in particular with components A), A') and / or B), in particular those surfactants which contribute to, or at least do not adversely affect, the delivery of components A) and / or A') to the skin.

[0188] Examples of useful nonionic surfactants may include esters of polyols and fatty acids containing saturated or unsaturated chains, and their oxyalkylene derivatives, i.e. derivatives containing oxyethylenated and / or oxypropylenated units, such as glycerol esters, and their oxyalkylene derivatives; polyethylene glycol esters and their oxyalkylene derivatives; sorbitol esters and their oxyalkylene derivatives; sugar (sucrose, glucose or alkyl glucose) esters and their oxyalkylene derivatives; fatty alcohol ethers; sugar ethers, and mixtures thereof.

[0189] Glycerol esters of fatty acids that may be mentioned in particular include glyceryl stearate (glyceryl monostearate, glyceryl distearate and / or glyceryl tristearate).

[0190] Polyethylene glycol esters of fatty acids that may especially be mentioned include polyethylene glycol 400E monostearate (CTFA name: PEG-40 Stearate).

[0191] Mixtures of these surfactants may also be used.

[0192] Matching the solubility of component A) and the properties of component B) and the medium / solvent to be used, component C) when used may preferably have an HLB value of 2-20, preferably 8-20, or preferably 10-18.

[0193] The nonionic surfactant may be present in the composition according to the invention in an amount ranging from 0.1% to 15% by weight, such as from 0.15% to 10% by weight, relative to the total weight of the composition.

[0194] Component D), medium / solvent

[0195] The composition according to the invention may advantageously comprise at least one medium / solvent, including water and / or an organic medium / solvent, for optional component D).

[0196] water

[0197] The composition according to the invention may advantageously contain various amounts of water. For low-viscosity applications of the composition, for example in the form of a leave-on lotion, relatively large amounts of water may be used. For example, water is used in an amount greater than or equal to 40% by weight relative to the total weight of the composition. The water content in the low-viscosity composition according to the invention is preferably 40% to 99% by weight, more preferably 50% to 90% by weight, or 60% to 80% by weight relative to the total weight of the composition.

[0198] For high viscosity applications of the composition, for example in the form of a leave-on cream, relatively low amounts of water can be used. The high viscosity composition according to the invention advantageously comprises water in a content of less than or equal to 40% by weight relative to the total weight of the composition. The water content in the high viscosity composition according to the invention is preferably from 10% to 40% by weight, more preferably from 15% to 35% by weight, or from 20% to 30% by weight, relative to the total weight of the composition.

[0199] Organic medium / solvent

[0200] The composition according to the invention may also comprise one or more organic media / solvents, preferably water-soluble organic media / solvents (solubility in water at 25° C. and atmospheric pressure greater than or equal to 5%; or having a log P ranging from −3.0 to 3.5, preferably from −3.0 to 0.5).

[0201] According to a preferred embodiment of the present invention, the composition may comprise at least one organic medium / solvent.

[0202] Examples of organic media / solvents that may be mentioned include linear or branched and preferably saturated mono- or diols containing from 2 to 10 carbon atoms, such as propylene glycol; aromatic alcohols; polyols containing more than two hydroxyl functions; polyol ethers, alone or as a mixture.

[0203] The organic medium / solvent, when they are present, is present in an amount ranging from 0.1% to 40% by weight, preferably from 1% to 30% by weight, or from 3% to 20% by weight relative to the total weight of the composition according to the invention.

[0204] pH Adjusters

[0205] The composition according to the present invention may contain (3) at least one pH adjuster (pH adjuster). Two or more pH adjusters may be used in combination. Thus, a single type of pH adjuster or a combination of different types of pH adjusters may be used.

[0206] As (3) the pH adjuster, at least one acidifying agent and / or at least one alkalizing agent (alkaline agent) may be used.

[0207] The acidulant may be a monovalent or polyvalent acid, such as a divalent acid.

[0208] The acidulant may be, for example, a mineral (inorganic) acid, such as hydrochloric acid, sulfuric acid, phosphoric acid, or an organic acid, such as a carboxylic acid, for example tartaric acid, citric acid and lactic acid, and a sulfonic acid.

[0209] The alkalizing agent may be a monovalent or polyvalent base, such as a divalent base.

[0210] Alkalizing agents may be mineral (inorganic) or organic, or a mixture.

[0211] The mineral alkalizing agent may be selected from aqueous ammonia; alkali metal carbonates or bicarbonates, such as sodium or potassium carbonate and sodium or potassium bicarbonate; alkali metal hydroxides, such as sodium hydroxide and potassium hydroxide; and mixtures thereof.

[0212] The organic alkalizing agent may be chosen 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 function of the highest basicity. Furthermore, the organic amine does not contain any alkyl or alkenyl fatty chain containing more than ten carbon atoms.

[0213] The organic alkalizing agent may be selected from, for example, alkanolamines, oxyethylenated and / or oxypropylenated ethylenediamines, amino acids and amine compounds of the following formula (III):

[0214]

[0215] in

[0216] W represents a C1-C6 divalent alkylene group, which is optionally substituted by one or more hydroxyl groups or C1-C6 alkyl groups and optionally interrupted by one or more heteroatoms such as O and N, and

[0217] R x , R y , R z and R t , which may be the same or different, represent a hydrogen atom or a C1-C6 alkyl, C1-C6 hydroxyalkyl or C1-C6 aminoalkyl group.

[0218] Examples of amine compounds of the formula (III) that may be mentioned include 1,3-diaminopropane, 1,3-diamino-2-propanol, spermine and spermidine.

[0219] The term "alkanolamine" refers to an organic amine comprising a primary, secondary or tertiary amine function and one or more linear or branched C1-C8 alkyl groups bearing one or more hydroxyl groups.

[0220] Alkanolamines containing one to three identical or different C1-C4 hydroxyalkyl groups, such as monoalkanolamines, dialkanolamines or trialkanolamines, may be suitable for the present invention. Among compounds of this type, mention may be made of monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N-dimethylaminoethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol and tris(hydroxymethylamino)methane.

[0221] The amino acids that can be used are of natural or synthetic origin, in their L, D or racemic form, and comprise at least one acid function more particularly chosen from carboxylic acid, sulfonic acid, phosphonic acid or phosphoric acid functions. The amino acids can be in neutral or ionic form.

[0222] As amino acids that can be used in the present invention, mention may be made especially of 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.

[0223] It may be preferred that the amino acid is a basic amino acid containing an additional amine function optionally contained in a ring or ureido function.

[0224] Such basic amino acids may preferably be selected from those corresponding to the following formula (IV):

[0225]

[0226] in

[0227] R represents a group selected from the following:

[0228]

[0229] -(CH2)3-NH2,

[0230] -(CH2)2-NH2,

[0231] -(CH2)2-NH-CO-NH2 and

[0232]

[0233] Compounds corresponding to formula (IV) include histidine, lysine, arginine, ornithine and citrulline.

[0234] The organic alkalizing agent may be chosen from organic amines of heterocyclic type. In addition to histidine already mentioned among the amino acids, mention may in particular be made of pyridine, piperidine, imidazole, triazole, tetrazole and benzimidazole.

[0235] The organic alkalizing agent may also be selected from amino acid dipeptides. As amino acid dipeptides that can be used in the present invention, mention may be made especially of carnosine, anserine and baleine.

[0236] The organic alkalizing agent may also be chosen from compounds containing a guanidine function. As amines of this type which may be used in the present invention, in addition to arginine already mentioned as an amino acid, mention may be made in particular of creatine, creatinine, 1,1-dimethylguanidine, 1,1-diethylguanidine, guanidinoacetic acid, metformin, agmatine, N-amidinoalanine, 3-guanidinopropionic acid, 4-guanidinobutyric acid and 2-([amino(imino)methyl]amino)ethane-1-sulfonic acid.

[0237] 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 a mixture thereof. Even more preferably, the organic alkalizing agent may be arginine.

[0238] Mixed compounds that may be mentioned include the salts of the previously mentioned amines with acids such as carbonic acid or hydrochloric acid. In particular, guanidine carbonate or monoethanolamine hydrochloride may be used.

[0239] The (3) pH adjuster may be present in an amount of 0.01 wt % or more, preferably 0.05 wt % or more, and more preferably 0.1 wt % or more, relative to the total weight of the composition.

[0240] The (3) pH adjuster may be present in an amount of 15 wt % or less, preferably 10 wt % or less, and more preferably 5 wt % or less, relative to the total weight of the composition.

[0241] The (3) pH adjuster may be present in an amount of 0.01 to 15 wt %, preferably 0.05 to 10 wt %, and more preferably 0.1 to 5 wt % or less, relative to the total weight of the composition.

[0242] Preferably the composition according to the invention has a pH of 4.5 or higher, and more preferably 5 or higher.

[0243] Preferably the composition according to the invention has a pH of 6.5 or lower, and more preferably 6 or lower.

[0244] Preferably the composition according to the invention has a pH of from 4.5 to 6.5, and more preferably from 5 to 6.

[0245] The pH of the composition refers to the pH of the aqueous phase of the composition according to the invention.

[0246] It may be preferred to use at least one buffer or buffering agent as (3) pH adjuster in combination with the acidifying agent and / or alkalizing agent to stabilize the pH of the composition according to the invention.

[0247] As buffer, any commonly known buffer can be used. For example, salts of acids or bases, preferably salts of weak acids or weak bases, can be used. For example, if citric acid or lactic acid is used as the acidulant, sodium citrate or sodium lactate can be used as the buffer.

[0248] Adjuvant

[0249] In a known manner, the composition of the invention may also contain adjuvants commonly used in the cosmetic, pharmaceutical and / or dermatological fields, depending on the final use and / or the specific product form, such as hydrophilic or lipophilic gelling agents, emulsifiers, hydrophilic or lipophilic active agents, preservatives, fragrances, fillers, pH regulators, odor absorbers and dyes. The amount of these various adjuvants is that conventionally used in the relevant field, and is, for example, 0.01% to 20% by weight of the total weight of the composition.

[0250] These adjuvants and their concentrations must be such that they do not alter the desired properties of the compositions of the invention.

[0251] The composition according to the invention is preferably in the form of an aqueous gel.

[0252] In a preferred embodiment according to the present invention, the composition comprises a hydrophilic gelling agent.

[0253] The composition according to the invention can be produced by known methods generally used in the field of cosmetics or dermatology.

[0254] The composition according to the invention finds application in many cosmetic treatments for keratin materials such as the skin, the scalp or mucous membranes (lips), and more particularly the skin, in particular for skin care to lighten the complexion.

[0255] A subject of the invention is also a cosmetic method for caring for or making up keratin materials, comprising applying to keratin materials a composition as defined above.

[0256] A subject of the invention is also a non-therapeutic cosmetic method for the care or make-up of keratin materials, comprising applying to them a composition as defined above.

[0257] The invention also relates to the cosmetic use of a composition as defined above for the care or make-up of keratin materials.

[0258] More particularly, a subject of the present invention is the cosmetic use of a composition as defined above for caring for the skin, preferably for lightening the complexion and / or reducing or lightening dullness and / or pigmented spots on the skin.

[0259] In a particular embodiment, the composition is suitable for treating dull and / or pigmented spots on the skin. Example

[0260] The following examples of compositions according to the invention are given by way of illustration and not limitation. The compounds are indicated by chemical name or INCI name.

[0261] Unless otherwise stated, the amounts / concentrations of ingredients in the compositions / formulations described below are expressed in weight % relative to the total weight of each composition / formulation.

[0262] The main raw materials used, their trade names and suppliers are listed below.

[0263]

[0264]

[0265] Compound 20 was synthesized as disclosed in Example 2 of patent EP3390363.

[0266] Example A

[0267] The compositions of the invention of Ex. 1-9 and the comparative compositions of CE. 1-2 were prepared from the ingredients shown in Table 1 below (wherein the contents are expressed in % by weight of the material relative to the total weight of the composition):

[0268] Table 1

[0269]

[0270] Taking Ex.1 as an example, the composition is prepared by the following steps:

[0271] 1) Heat the fat compound to 75°C and mix thoroughly until all solids are melted.

[0272] 2) Mix the soluble raw materials and heat to 75°C, mix thoroughly until there are no lumps.

[0273] 3) Transfer the oil phase to the water phase at 75°C and mix evenly for 15 minutes.

[0274] 4) Cool to 30C.

[0275] 5) Finally, compound 20 was added and the pH was adjusted to 5.6±0.3.

[0276] Example B

[0277] The compositions of the invention of Ex. 1-9 and comparative compositions of CE. 1-2 prepared in Example A were evaluated via Raman spectroscopy and bioavailability studies.

[0278] Raman spectroscopy:

[0279] A LabRam HR Evolution (Horiba Jobin-Yvon, Illeneuve-d'Ascq, France) Raman confocal microscope was used. Raman spectra were acquired using a 532 nm DPSS laser with 8 mW power on the sample coupled to a ×50 LM Plan (Olympus, NA 0.75, Rungis, France) objective. For all measurements, the confocal aperture was set at 100 μm diameter. The system spectrum was calibrated to 520.7 cm -1 Silicon spectroscopic lines before testing. Detection is facilitated by spreading the Raman-shifted radiation onto a charge-coupled device (CCD) detector using a 600 lines / mm grating.

[0280] For the pure active ingredient, 25% laser intensity and 10 s acquisition time were used for the 400-2000 cm -1 spectral range to collect single-point spectra.

[0281] For mapping in the recipe test, the step size was 3 μm in both the X and Y directions. The acquisition area was 18 × 150 μm. For each spot, 50% laser intensity and an acquisition time of 5 seconds per spectrum were used. The spectral range was 400–2000 cm -1 .

[0282] For the test, skin tissue samples were prepared as follows: For sample preparation, 6 μl of the formulation was evenly applied on 0.8 cm × 0.8 cm pig skin, corresponding to 9 mg / cm 2 . The pig skin samples were then exposed on an insert membrane with PBS underneath, followed by incubation at 37°C for 6 hours at 95% RH. The treated samples were embedded in OCT and subsequently frozen and cryosectioned to 20 μm thickness. They were further placed on a CaF2 substrate for Raman confocal scanning. Three pig skin samples were prepared for each formulation. Raman confocal imaging of each treated sample was obtained.

[0283] Bioavailability Studies:

[0284] For percutaneous absorption studies, vertical diffusion cells were used. The studies were conducted using the following procedure: the formulation containing the active of interest was diffused at 5 mg / cm 2 Apply to skin samples (n=9). After 16 hours of exposure, wash off the unabsorbed residue remaining on the skin surface, then collect the stratum corneum by tape stripping (20 times, 10 times combined), collect the epidermis, dermis and receiving fluid. Extract the active from each compartment collected: washing, tape stripping, epidermis, dermis and receiving fluid, and quantify the amount of active by LC MS / MS. Check the mass balance to see if the applied amount of T on the skin is recovered at the end of the experiment; exclude the data when the mass balance does not meet the criterion of 100±15%.

[0285] Table 2 Active delivery data in bioavailability testing - corresponding to Table 1

[0286] nature Ex.1 Ex.2 Ex.3 Ex.4 Ex.5 Ex.6 Ex.7 Ex.8 Ex.9 CE.1 CE.2 Raman (Compound 20) √ √ √ √ √ Δ Δ × Raman (TXA) Δ Δ ○ Δ × Bioavailability (Compound 20) 315％ 148％ Bioavailability (TXA) 2.3％ 2.3％ 0.11％

[0287] √: Signals can be observed in the stratum corneum and epidermis;

[0288] Δ: sparse signals can be found in the epidermis;

[0289] ○: weak signals can be found in the epidermis; and

[0290] ×: No signal was observed in the skin.

[0291] The results are also provided in Figure 1 and Figure 2 For compound 20, signals were observed in both the stratum corneum and epidermis in Ex.1, Ex.4, Ex.5, Ex.6, Ex.7, Ex.8, and Ex.9, while no signal was found in CE.2. For the TXA active, weak or sparse signals were found in the epidermis in Ex.2, Ex.4, Ex.6, and Ex.7, while no signal was found in CE.1.

[0292] Table 3: Bioavailability data

[0293]

[0294] Bioavailability results are shown in Table 3. For the examples of the invention, high % of applied dose in skin were obtained for the sample formulations, especially more than 1% active in (epidermis+dermis+RF); whereas in CE.1 and CE.2 less active was found in the skin.

[0295] Example C

[0296] The compositions of the invention of Ex.10-11 and the comparative composition of CE.3 were prepared from the ingredients shown in Table 2 below (wherein the contents are expressed in % by weight of the material relative to the total weight of the composition):

[0297] Table 4

[0298] Components Ex.10 Ex.11 CE.3 PEG-40 Stearate 1.2 1.2 1.2 Sucrose tristearate 0.5 0.5 0.5 glycerin 9 9 9 Ethyl oleate 1 Hexyldecanol 1 Ethyl linoleate 3 Tranexamic acid 1 1 1 Niacinamide 4 4 4 Compound 20 0.5 0.5 0.5 water Make up 100 Make up 100 Make up 100

[0299] Example D

[0300] The inventive compositions of Ex. 10-11 prepared in Example C and the comparative composition of CE.3 were evaluated via Raman spectroscopy as described in Example B.

[0301] The results are shown in Figure 3 The three formulations were comparable in terms of compound 20 signal intensity and depth in pig skin, and all signals could be observed in the stratum corneum, epidermis, and dermis.

[0302] The results are also shown in Figure 4 For Ex.10, the TXA signal was evenly distributed in the stratum corneum, epidermis, and dermis. However, for Ex.11 & CE.3, no obvious signal was observed in the epidermis, only in the stratum corneum and dermis.

[0303] It can be concluded that by adopting the technical solution of the present invention and using a fat compound having at most one C=C bond, the formulation can achieve the penetration of active substances comparable to that of conventional fat compounds having 2 or more C=C bonds, but suppresses or even avoids the defect of storage instability caused by more C=C bonds.

Claims

1. A composition comprising the following components: A) at least one compound selected from the group consisting of the following compounds of formula (I) and tautomers of formula (I'); and their salts, optical isomers, racemates and / or solvates such as hydrates, alone or as a mixture: In formula (I) and (I'): -R1 represents a group selected from the following: a) Hydrogen atom; b) Saturated straight chain C1-C 10 or branched C3-C 10 Alkyl, which is optionally substituted by one or more groups, which may be the same or different, selected from: i)-O-R3 ii) -S-R3; -R2 represents a group selected from the following: a) Hydrogen atom; b) Saturated straight chain C1-C 12 or branched C3-C 12 or a cyclic C3-C8 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from: i)-O-R3 ii)-S-R3 iii) -C(O)-O-R3; iv) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups; c) C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups; -R3 represents a group selected from the following: a) Hydrogen atom; b) Saturated straight chain C1-C 10 or branched C3-C 10 alkyl; B) at least one C12-20 fatty compound, preferably a C12-C18 fatty compound, or preferably a C12-C16 fatty compound, having at most one C═C bond, with the proviso that when component B) is a fatty acid, it is a C12-C16 fatty acid.

2. The composition according to claim 1, wherein: - R1 of formula (I) or (I') represents a hydrogen atom, or - R1 in formula (I) or (I') represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially linear (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably ethyl, in particular, the alkyl of R1 is unsubstituted.

3. A composition according to any one of the preceding claims, wherein: - R2 in formula (I) or (I') represents a hydrogen atom; or - R2 in formula (I) or (I') represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; the alkyl of R2 is unsubstituted.

4. The composition according to claim 1 or 2, wherein: - R2 in formula (I) or (I') represents a straight chain (C1-C 10 ) alkyl or branched (C3-C 10 )alkyl, especially straight-chain (C1-C6)alkyl or branched (C3-C6)alkyl, such as methyl, ethyl, n-pentyl, n-nonyl, isobutyl, more preferably methyl or ethyl; the alkyl is substituted by one or more groups selected from i), ii), iii) and iv) as defined in claim 1, preferably the alkyl is substituted by one or two groups selected from i), ii) and iii), more preferably substituted by one or two groups selected from i) and iii), and more preferably substituted by a carboxyl group iii).

5. The composition according to claim 1 or 2, wherein: - R2 in formula (I) or (I') represents a (C3-C8) cycloalkyl group, preferably a (C5-C7) cycloalkyl group such as a cyclohexyl group; or - R2 in formula (I) or (I') represents a C5-C8 alkoxy group optionally substituted by one or more hydroxyl groups and / or by one or more C1-C8 alkoxy groups; 12 Aryl, preferably phenyl, is in particular unsubstituted.

6. A composition according to any one of the preceding claims, wherein - R3 in formula (I) or (I') represents a hydrogen atom; or - R3 in formula (I) or (I') represents a saturated straight chain C1-C 10 or branched C3-C 10 Alkyl; in particular straight chain (C1-C6) alkyl or branched chain (C3-C6) alkyl, preferably (C1-C4) alkyl such as methyl.

7. A composition according to any one of the preceding claims, wherein: - R1 in formula (I) or (I') represents a group selected from the following: a) Hydrogen atom; b) a saturated straight-chain C1-C6 or branched C3-C6 alkyl group, which is optionally substituted by one or more groups, which may be the same or different, selected from: i)-O-R3 ii) -S-R3; Preferably, it is optionally substituted by one or more groups i) - R2 in formula (I) or (I') represents a group selected from the following: -a) Hydrogen atom; -b) Saturated straight chain C1-C 10 or branched C3-C 10 or a cyclic C3-C8 such as C5-C6 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from: -i)-O-R3 -ii)-S-R3 -iii)-C(O)-O-R3; -iv) phenyl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C4alkoxy groups such as methoxy; - preferably substituted by one or more groups selected from i) and iii), preferably substituted by iii) such as carboxyl - R3 in formula (I) or (I') represents a group selected from the following: -a) Hydrogen atom; -b) Saturated straight chain C1-C6 or branched C3-C6 alkyl - preferably, compounds of formula (I) and tautomers (I') or their salts, their optical isomers, racemates and / or their solvates such as hydrates, alone or as a mixture; - has the following meanings: - R1 in formula (I) or (I') represents a group selected from the following: -a) Hydrogen atom; -b) saturated linear C1-C4 or branched C3-C4 alkyl, optionally substituted by one or more groups, which may be the same or different, selected from i) -OR3, more preferably unsubstituted; - R2 in formula (I) or (I') represents a group selected from the following: -a) Hydrogen atom; -b) Saturated straight chain C1-C 10 or branched C3-C 10 or a cyclic C3-C8 such as C5-C6 hydrocarbon group, which is optionally substituted by one or more groups, which may be the same or different, selected from: -i)-O-R3 -iii)-C(O)-O-R3; -iv)C5-C 12 Aryl, which is optionally substituted by one or more hydroxyl groups and / or by one or more C1-C4alkoxy groups; - R3 in formula (I) and (I') represents a group selected from the following: -a) Hydrogen atom; -b) saturated straight-chain C1-C4 or branched C3-C4 alkyl groups, such as methyl or ethyl.

8. A composition according to any one of the preceding claims, wherein The compound of formula (I) is selected from the following compounds 1 to 24 and their tautomers or their salts, their optical isomers, racemates, and / or their solvates such as hydrates, alone or as a mixture, in particular compounds 1, 2, 4, 6, 7, 9, 11, 12, 14, 15, 16, 17, 18, 19, 20 or 21, more in particular 1, 9, 16, 18, 19, 20 or 21, preferably 18, 19, 20 or 21, more preferably 20:

9. The composition according to any one of the preceding claims, wherein the component A) is selected from those having a log P falling within the range of -1.6 to 0.

5.

10. The composition according to any one of the preceding claims, wherein an additional hydrophilic active compound having a log P of from -1.6 to 0.5 is used in combination with component A), preferably selected from water-soluble vitamins, cosmetically acceptable derivatives of niacinamide and tranexamic acid, preferably ascorbic acid, niacinamide or tranexamic acid.

11. The composition according to any one of the preceding claims, wherein the components A) and / or A') are present in an amount of 0.01 to 20 wt. %, preferably 0.05 to 10 wt. %, or preferably 0.1 to 5 wt. %, relative to the total weight of the composition.

12. The composition according to claim 1, wherein the component B) is selected from fatty alcohols, fatty acids, fatty acid esters and / or fatty alcohol esters, in particular selected from Lauryl alcohol, oleyl alcohol and mixtures thereof; Lauric or lauroleic acid (C12), myristic or myristoleic acid (C14), palmitic or palmitoleic acid (C16); Cetyl Lactate; Lactic Acid C 12 -C 15 alkyl esters; lauryl lactate; oleyl lactate; octyl octanoate; isononyl isononanoate; octyl isononanoate; 2-ethylhexyl isononanoate; octyl nonanoate; ethyl palmitate and isopropyl palmitate; alkyl myristates such as butyl myristate, myristate, laurate or ethyl oleate; and Diethyl sebacate; diisopropyl sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl maleate; glyceryl undecylenate; propylene glycol dicaprylate; triisopropyl citrate; glyceryl trilactate.

13. The composition according to any one of the preceding claims, further comprising as component C) a nonionic surfactant selected from esters of (poly)alcohols with fatty acids having saturated or unsaturated chains having 21 or more carbon atoms.

14. The composition according to claim 13, wherein the component C) has an HLB value of 2-20, preferably 8-20, or preferably 10-18.

15. The composition according to any of the preceding claims, further comprising water and / or an organic medium / solvent as component D), the organic medium / solvent being preferably selected from linear or branched mono- or diols containing 2 to 10 carbon atoms; aromatic alcohols such as phenethyl alcohol; polyols containing more than two hydroxyl functions, such as glycerol; polyol ethers, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and ethylene glycol monobutyl ether, propylene glycol or its ethers, such as propylene glycol monomethyl ether; and mixtures thereof.

16. A composition according to any one of the preceding claims, wherein the organic medium / solvent is preferably present in an amount of 0.1% to 40% by weight, preferably 1% to 30% by weight, or 3% to 20% by weight, relative to the total weight of the composition.

17. Use of a combination of the following components for enhancing the delivery of component A) into the skin: Component A) Active compound having a log P of -1.6 to 0.5 Component B) a C12-20 fatty compound, preferably a C12-C18 fatty compound, or preferably a C12-C16 fatty compound, having at most one C═C bond; and Optional component C); a surfactant having an HLB value of 2-20, preferably 8-20, or preferably 10-18; and Optional component D); diols having a log P of -3.0 to 3.5, preferably -3.0 to 0.

5.

18. A non-therapeutic cosmetic method for depigmenting, lightening and / or bleaching keratinous material, preferably skin, comprising the steps of: Applying a composition according to any one of claims 1 to 16 to the keratin material.

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