Patent ID: 8563754

Claim:
A method for preventing the hyperpigmentation or undesired darkening of skin comprising administering to a subject in need thereof an effective amount of either lonchocarpic acid or a compound of formulae IIIa, IIIb, IIIc or IIId: or a pharmaceutically acceptable salt, solvate or prodrug thereof, and stereoisomers, tautomers and isotopic variants thereof; and wherein R 4 is selected from H, halo, hydroxy, alkoxy, alkenyloxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, and substituted or unsubstituted phenyl; R 5 and R 6 are independently selected from H, halo, hydroxy, alkoxy, alkenyloxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, and substituted or unsubstituted phenyl; R 3 is selected from halo, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, phenyl, 3,4-dihydroxyphenyl, 4-methoxyphenyl, or 3,4-dimethoxyphenyl; R 8 is selected from H, halo, hydroxy, alkoxy, alkenyloxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, or substituted or unsubstituted phenyl; and each R 6a , R 7a and R 7b is independently selected from H, alkyl, hydroxyalkyl, or alkenyl.