Acredinones A and B, Voltage-Dependent Potassium Channel Inhibitors from the Sponge-Derived Fungus Acremonium sp F9A015

Two new benzophenones, acredinones A (1) and B (2), were isolated from a marine-sponge-associated Acremonium sp. fungus. Their chemical structures were elucidated on the interpretation of spectroscopic data. The structure of 1 was confirmed by palladium-catalyzed hydrogenation, followed by spectroscopic data analysis. Acredinones A (1) and B (2) inhibited the outward K+ currents of the insulin secreting cell line INS-1 with IC50 values of 0.59 and 1.0 mu M, respectively.