Virgatolides A - C, benzannulated spiroketals from the plant endophytic fungus Pestalotiopsis virgatula

摘要

Virgatolides A-C (1-3), unique metabolites with a 3′,4′, 5′,6′-tetrahydrospiro[chroman-2,2′-pyran] core, were isolated from cultures of the plant endophytic fungus Pestalotiopsis virgatula. Compounds 1-3 possess two previously undescribed skeletons originating from a benzannulated 6,6-spiroketal and one (2 and 3) and two (1) γ-lactone units, respectively. The structure of 1 was secured by X-ray crystallography.