Process for depigmenting keratin materials using thiopyridinone compounds

Abstract

The invention relates to a cosmetic process for depigmenting, lightening and/or whitening keratin materials, in particular the skin, which comprises the application of a cosmetic composition comprising a compound of formula (I):or its tautomer form of formula (I′):in which:R1 and R2, which may be identical or different, denote a radical chosen from:a) a hydrogen atom;b) a C1-C20 alkyl group optionally interrupted with N, S or O, optionally substituted with one or more group(s) chosen from -—OR3, —SR3, —NR3R4, —CONHR3; —COORS; and an aryl group optionally substituted with one or more hydroxyls and/or with one or more C1-C8 alkoxy radicals;c) a C1-C8 alkyl group substituted with a C5-C12 aryl radical optionally substituted with one or more hydroxyls and/or with one or more C1-C8 alkoxy radicals;d) a phenyl group optionally substituted with one or more hydroxyls and/or with one or more C1-C8 alkoxy radicals;R3 denoting H or a C1-C5 alkyl group,R4 denoting H, a C1-C5 hydrocarbon-based group or an acetyl group;it being possible for R1 and R2 to form, with the nitrogen atom which bears them, a ring chosen from pyrrolidine, pyrroline, piperidine, piperazine, morpholine, thiomorpholine and azepine.The invention also relates to the cosmetic use of a compound (I) or (I′) as a whitening, lightening and/or depigmenting agent for keratin materials.

1 . Nontherapeutic cosmetic process for depigmenting, lightening and/or whitening keratin materials, which comprises the application of a cosmetic composition comprising, in a physiologically acceptable medium, at least one compound of formula (I): 
       
         
           
           
               
               
           
         
         or its tautomer form of formula (I′): 
       
       
         
           
           
               
               
           
         
         in which: 
         R 1  and R 2 , which may be identical or different, denote a radical chosen from:
 a) a hydrogen atom; 
 b) a saturated linear C 1 -C 20  or branched C 3 -C 20  or unsaturated C 2 -C 20  alkyl group, optionally interrupted with one or more heteroatoms chosen from N, S and O, and/or optionally substituted with one or more groups, which may be identical or different, chosen from:
 i) —OR 3    
 ii) —SR 3 , 
 iii) —NR 3 R 4    
 iv) —CONHR 3    
 v) —COOR 3 ; 
 vi) a C 5 -C 12  aryl group optionally substituted with one or more hydroxyls and/or with one or more C 1 -C 8  alkoxy radicals; 
 
 c) a saturated C 1 -C 8  alkyl group substituted with a C 5 -C 12  aryl radical optionally substituted with one or more hydroxyls and/or with one or more C 1 -C 8  alkoxy radicals; 
 d) a phenyl group optionally substituted with one or more hydroxyls and/or with one or more C 1 -C 8  alkoxy radicals; 
 
         R 3  denoting a hydrogen atom or a saturated linear C 1 -C 5  or branched C 3 -C 5  or unsaturated C 2 -C 5  hydrocarbon-based group, 
         R 4  denoting a hydrogen atom; a saturated linear C 1 -C 5  or branched C 3 -C 5  hydrocarbon-based group; or an acetyl group; 
         it being possible for R 1  and R 2  to form, with the nitrogen atom which bears them, a ring chosen from pyrrolidine, pyrroline, piperidine, piperazine, morpholine, thiomorpholine and azepine; 
         and also the salts thereof, the optical isomers thereof and the racemates thereof.