Study on Secondary Metabolites of Marine-Derived Fungus Eutypella sp. F0219

The fungus Eutypella sp. is well known for producing bioactive compounds with diverse structures. Chemical investigation of the fungi Eutypella sp. F0219 isolated from marine sediment, yielded a new prenylated dihydroisocoumarin and a new chromene amide derivative, named eutypellarins A and B (1 and 2), together with two known prenylated benzaldehyde derivatives (3 and 4). The structures of these compounds were elucidated based on HR-ESIMS, extensive nucler magneti resonance (NMR) experiments, and quantum-chemical electronic circular dichroism (ECD) calculations. Prenylated dihydroisocoumarin and chromene amide derivatives are reported from the genus Eutypella for the first time. The total antioxidant capacities of all compounds were measured through 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and ferric-reducing antioxidant power (FRAP) assay. The results showed that compounds 1 and 4 exhibited moderate antioxidant properities with Trolox equivalent antioxidant capacity (TEAC) values (0.51 +/- 0.016) and (0.76 +/- 0.007), respectively.