Two new dihydroisocoumarins with antimicrobial activities from the fungus Penicillium sp. XR046 collected from Xinren coal area.

Two new dihydroisocoumarins (1 and 2), together with six known compounds (3-8), were isolated from the fungus Penicillium sp. XR046 collected from the Xinren coal area of Guizhou province in China. Their structures were elucidated on the basis of spectroscopic analysis. The absolute configurations of C-3 in 1 and 2 were established by comparison of their CD data with those of known compounds. Compounds 1-6 showed anti-microbial activities with MIC values in the range of 50∼100 µg/mL against Candida albicans, Staphylococcus epidermidis, Bacillus subtilis, and Escherichia coli.