Pyridone alkaloids from a marine-derived fungus, Stagonosporopsis cucurbitacearum, and their activities against azole-resistant Candida albicans.

Four new 4-hydroxy-2-pyridone alkaloids, didymellamides A-D (1-4), were isolated from the marine-derived fungus Stagonosporopsis cucurbitacearum. The structures of 1-4 were elucidated from spectroscopic data (NMR, MS, and IR), and the absolute configuration of 1 was determined by X-ray diffraction analysis. Didymellamide A (1) exhibited antifungal activity against azole-resistant Candida albicans.