Cosmetic use of at least one compound corresponding to the following formula or (I'): in which formulae: R1 and R2, which are 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 by one or more heteroatoms chosen from N, S and O, and/or optionally substituted by one or more identical or different groups chosen from: i) -OR3, ii) -SR3, iii) -NR3R4, iv) -CONHR3, or v) -COOR3; c) a saturated C 1 -C 8 alkyl group substituted by at least one C 5 -C 12 aryl radical, said aryl radical optionally being substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; or d) a phenyl group optionally substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; R3 denoting a hydrogen atom or a saturated linear C 1 -C 6 or branched C 3 -C 6 or unsaturated C 2 -C 5 alkyl group, R4 denoting a hydrogen atom, a saturated linear C 1 -C 5 or branched C 3 -C 5 hydrocarbon 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; and also their salts, their solvates, their optical isomers and their racemates, as inhibitor of the black or brown colouration of comedones. R1 and R2, which are 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 by one or more heteroatoms chosen from N, S and O, and/or optionally substituted by one or more identical or different groups chosen from: i) -OR3, ii) -SR3, iii) -NR3R4, iv) -CONHR3, or v) -COOR3; c) a saturated C 1 -C 8 alkyl group substituted by at least one C 5 -C 12 aryl radical, said aryl radical optionally being substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; or d) a phenyl group optionally substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; 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 by one or more heteroatoms chosen from N, S and O, and/or optionally substituted by one or more identical or different groups chosen from: i) -OR3, ii) -SR3, iii) -NR3R4, iv) -CONHR3, or v) -COOR3; i) -OR3, ii) -SR3, iii) -NR3R4, iv) -CONHR3, or v) -COOR3; c) a saturated C 1 -C 8 alkyl group substituted by at least one C 5 -C 12 aryl radical, said aryl radical optionally being substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; or d) a phenyl group optionally substituted by one or more hydroxyls and/or by one or more C 1 -C 8 alkoxy radicals; R3 denoting a hydrogen atom or a saturated linear C 1 -C 6 or branched C 3 -C 6 or unsaturated C 2 -C 5 alkyl group, R4 denoting a hydrogen atom, a saturated linear C 1 -C 5 or branched C 3 -C 5 hydrocarbon 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; and also their salts, their solvates, their optical isomers and their racemates, as inhibitor of the black or brown colouration of comedones.