A new alkaloid from Thespesia populnea endophytic fungus Penicillium sp. TM-Y1-1.

A new alkaloid (3), together with three known compounds, were isolated from the Thespesia populnea endophytic fungus TM-Y1-1. Their structures were elucidated by extensive spectroscopic methods. The absolute configuration of compound 3 was determined for the first time by ECD calculation and DP4+ analysis. All compounds were evaluated for antimicrobial activity. The results showed that compounds 1 and 2 both exhibited moderate inhibitory activity against banana Colletotrichum gloeosporioides with MIC value of 31.25 µg/ml.