Butyrolactones from the Fermentation Products of the Endophytic Fungus Aspergillus versicolor

Two new butyrolactones, versicolactones E-F (1 and 2), along with three known butyrolactones (3-5), were isolated from the fermentation products of the endophytic fungus Aspergillus versicolor. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. The anti-tobacco mosaic virus (anti-TMV) activities of 1-5 were evaluated. Compounds 1-5 showed modest anti-TMV activities with inhibition rates of 14.6-18.8%.