A new spiroketal from Aspergillus terreus, an endophytic fungus in Opuntia ficusindica Mill.

A new spiroketal, named aspergiketal (1) was isolated from the culture broth of Aspergillus terreus, an endophytic fungus in the stems of the plant Opuntia ficusindica Mill., together with two known compounds, physcion (2) and asterric acid (3). Their structures were elucidated by spectroscopic methods including 2D-NMR techniques.