Patent ID: 8329149

Claim:
A topical skin lightening composition, comprising a substituted-4-oxobutanoic acid, ester, or amide skin depigmenting agent of Formula I: wherein, where Z is a sulfur atom or a group NR N , wherein R N is selected from H, alkyl of 1 to 6 carbons, or cycloalkyl of 3 to 6 carbons, G is an aryl of 6 to 10 carbons optionally substituted with R 3 -R 4 ; R 3 represents, independently at each occurrence, a bond without R 3 or one of the following: (i) an aliphatic C 1 -C 20 hydrocarbon radical; (ii) a C 1 -C 20 aromatic hydrocarbon radical; or (iii) a C 1 -C 20 heteroaryl radical; R 4 is selected independently at each occurrence from hydrogen; —F; —Cl; —Br; —I; —OH, —OR; —NH 2 ; —NHR; —N(R) 2 ; —N(R) 3 + ; —N(R)—OH; —N(O)(R) 2 ; —O—N(R) 2 ; —N(R)—O—R; —N(R)—N(R) 2 ; —C═N—R; —N═C(R) 2 ; —C═N—N(R) 2 ; —C(═NR)—N(R) 2 ; —SH; —SR; —CN; —NC; —CHO; —CO 2 H; —CO 2 ; —CO 2 R; —(C═O)—S—R; —O—(C═O)—H; —O—(C═O)—R; —S—(C═O)—R; —(C═O)—NH 2 ; —(C═O)—N(R) 2 ; —(C═O)—NHNH 2 ; —O—(C═O)—NHNH 2 ; —(C═S)—NH 2 ; —(C═S)—N(R) 2 ; —N(R)—CHO; —N(R)—(C═O)—R; —(C═NR)—O—R; —O—(C═NR)—R, —SCN; —NCS; —NSO; —SSR; —N(R)—C(═O)—N(R) 2 ; —N(R)—C(═S)—N(R) 2 ; —SO 2 —R; —O—S(═O) 2 —R; —S(═O) 2 —OR; —N(R)—SO 2 —R; —SO 2 —N(R) 2 ; —O—SO 3 − ; —O—S(═O) 2 —OR; —O—S(═O)—OR; —O—S(═O)—R; —S(═O)—OR; —S(═O)—R; —NO; —NO 2 ; —NO 3 ; —O—NO; —O—NO 2 ; —N 3 ; —N 2 R; —N(C 2 H 4 ); —Si(—R) 3 ; —CF 3 ; —O—CF 3 ; —(C═O)—R; —PR 2 ; —O—P(═O)(OR) 2 ; —P(═O)(OR) 2 ; ═O; ═S; ═NR; an aliphatic C 1 -C 20 hydrocarbon radical; a C 1 -C 20 aromatic hydrocarbon radical; or a C 1 -C 20 heteroaryl radical; R 1 and R 2 are each selected from: H, alkyl of 1 to 6 carbons, or cycloalkyl of 3 to 6 carbons; X is oxygen or nitrogen; Y is H, alkyl of 1 to 6 carbons; alkoxyalkyl of 2 to 12 carbons; or G substituted with R 3 -R 4 ; Q is alkyl of 1 to 10 carbons, cycloalkyl of 3 to 6 carbons, alkylaryl the alkyl of which has 1 to 6 carbons and said aryl has 6 to 10 carbons, or optionally substituted with R 3 -R 4 ; n is 0, 1, or 2, with the proviso that when Z is NR N , n will be zero; and a cosmetically, dermatologically or pharmaceutically acceptable vehicle.