Isochromophilones from an endophytic fungus Diaporthe sp.

Three new azaphilone compounds, isochromophilones X–XII (1–3), together with two known ones sclerotioramine (4) and isochromophilone VI (5) were isolated from the cultures of an endophytic fungus Diaporthe sp. The structures were elucidated by extensive HRESIMS and NMR spectroscopic analyses. All compounds were tested for their cytotoxicities against five human cancer cell lines by MTT method, among which compound 1 showed moderate inhibitory effects on these cell lines. This was the first report of azaphilones isolated from Diaporthe sp.