COUMARINS WITH ANTI-MELANOGENESIS ACTIVITIES FROM A CHEMICALLY ENGINEERED EXTRACT OF A MARINE-DERIVED FUNGUS

Chemical investigation of new resources is critical for developing medicinal leads. Chemically engineered extracts, a technique for derivatization of natural extracts, was performed on crude extracts of marine-derived fungus Eurotium rubrum; the resulting reaction mixture exhibited enhanced tyrosinase inhibition. Coumarin derivatives (1-3) were isolated from this chemically engineered extract. The structures of 1-3 were established using NMR, MS, and IR methods, revealing coumarin structures with side chains biosynthesized by the acetate-malonate pathway. 1-3 showed tyrosinase inhibition (IC50 = 7.7, 13.3, and 9.5 mu M, respectively) and anti-melanogenesis activity (IC50 = 6.6, 7.2, and 6.6 mu M, respectively, against B16 melanoma cells).