Previously, we synthesized (Z)-5-(3-hydroxy-4-methoxybenzylidene)-2-iminothiazolidin-4-one (MHY773, Fig. 1), which possesses a 2-iminothiazolidin-4-one template, and found this compound potently inhibited mushroom tyrosinase (IC50 = 2.87 μM for monophenolase and 8.06 μM for diphenolase) and melanogenesis in B16F10 melanoma cells [56]. This evidence concerns the gene TYR and melanoma.