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%.