In this study, a new skin-depigmenting agent, 2,6-dimethoxy-N-(4-methoxyphenyl)benzamide (DMPB), was synthesized using a combination
of benzoic acid and aniline. DMPB exhibited significant depigmentation ability on the UV B-induced hyperpigmentation of the
brown guinea pig skin. In addition, the 100 ppm treatment with this compound had a 30% inhibitory effect on melanin pigment generation
in the melan-a cell line without significant cell toxicity. To search for relationship with the depigmentation, the effects of DMPB on
the tyrosinase and dopachrome tautomerase were evaluated. DMPB had no effect on tyrosinase. However, it accelerated dopachrome
transformation into 5,6-dihydroxyindole-2-carboxylic acid (DHICA) in the presence of dopachrome tautormerase. In addition, intracellular
level of dopachrome tautomerase in melan-a cells was increased by treatment of DMPB. These results suggest that the pigmentlightening
effects of DMPB might be due to biased production of DHICA-eumelanin induced by dopachrome tautormerase activation.