A New α-Pyrone Derivative from Endophytic Fungus Pestalotiopsis microspora

A new alpha-pyrone derivative 1, along with four known congeners 2, 3, 4 and 5, were isolated from the solid-substrate fermentation medium of the endophytic fungus Pestalotiopsis microspore isolated from the branch of Taxus chinensis. Their structures and relative configurations were elucidated by extensive spectroscopic analysis. The cytotoxic activities of the isolated alpha-pyrone derivatives against two tumor cell lines as well as compound l's antimicrobial activity against three bacteria and three plant-pathogenic strains were evaluated. No antimicrobial activity was observed for compound 1. The cytotoxicity against Caski and HeLa tumor cell lines was insignificant. To our surprise, the known compound 4 showed significant gibberellin synergistic activity towards Distyhum chinense seeds.