Chrysomutanin and related meroterpenoids from a DES mutant of the marine-derived fungus S-3-25.

A new meroterpene, chrysomutanin (), two new meroterpenoids ( and ) together with nine known ones were isolated from the diethyl sulphate (DES) mutant 3d10-01 of the marine-derived fungus S-3-25. The structures of the isolated compounds were determined by their spectroscopic data, and the absolute configuration of was determined by Rh-induced electrical circular dichroism (ECD) analysis or by comparison of the measured ECD with that of the known compounds. The cytotoxic activity was preliminarily evaluated against five human cancer cell lines. HPLC-UV analysis showed that compounds - were all newly produced by the mutant, and were not detected from the initial strain S-3-25. Chrysomutanin () is a new member with a chain sesquiterpene unit to the family of meroterpenes. Present results confirm that DES mutagenesis strategy is an effective method to exploit the dormant metabolites of fungi.