Five Unreported Ketone Compounds-Penicrustones A-E-From the Endophytic Fungus Penicillium crustosum

Five unreported ketone compounds-penicrustones A-E-were isolated from the solid fermentation of the endophytic fungus Penicillium crustosum. Their structures were elucidated on the basis of extensive spectroscopic analysis. Their absolute configurations were determined via ECD calculations and single-crystal X-Ray crystallography. All compounds were evaluated for their antimicrobial and antitumor activities. Compounds 4 and 5 showed moderate inhibitory effects on Micrococcus luteus, with MIC values of 12.5 and 25.0 μg/mL, respectively. In addition to this, compound 4 also showed cytotoxicity on tumor cell lines KTC-1 and Hela, with IC₅₀ values of 4.28 and 4.64 μg/mL, respectively.