Penpolonin A-E, cytotoxic α-pyrone derivatives from Penicillium polonicum.

Five new α-pyrone derivatives, named penpolonin A-E (1-5), together with two known compounds (6-7) were acquired from the endophytic fungus Penicillium polonicum isolated from the roots of Camptotheca acuminata Decne. Their structures were established by combination of NMR and HRESIMS data and the absolute configurations of 1-5 were determined by NMR calculations and comparison of experimental and calculated ECD data. Compounds 3 and 7 exhibited moderate cytotoxicity against Hep-2, TU212 human laryngeal cancer cells with IC50 values ranging from 31.6 to 45.1 μg/ml, compound 4 showed weak cytotoxicity against the Hep-2 and TU212 cell lines with IC50 values of 69.2 and 68.7 μg/ml.