Thiazolo[5,4-b]pyridine Alkaloid and Seven ar-Bisabol Sesquiterpenes Produced by the Endophytic Fungus Penicillium janthinellum.

We investigated the secondary metabolites present in Penicillium janthinellum MPT-25, an endophytic fungus isolated from Taxus wallichiana var. chinensis (Pilger) Florin. Chemical characterization of the solid cultured extract resulted in the isolation of 11 compounds, including eight previously undescribed metabolites: a thiazolo[5,4-b]pyridine alkaloid, janthinedine A (1), and seven ar-bisabol sesquiterpenes, janthinepenes A-G (2-8). Their structures were elucidated by a combination of extensive spectroscopic methods, including single-crystal X-ray diffraction and ECD spectra. The antimicrobial activities of these compounds were evaluated against seven agricultural pathogenic fungi and eight clinically drug-resistant bacteria.

New chromone analog and pyrrole alkaloid produced by Penicillium sclerotiorum and their antibacterial activity.

A new chromone analog (1) and a new pyrrole alkaloid (2), together with four known compounds, were isolated from the endophytic fungus Penicillium sclerotiorum MPT-250 obtained from the stems of Taxus wallichiana var. chinensis (Pilger) Florin. The structural elucidation of these metabolites was performed by high-resolution mass spectrometry and NMR spectroscopy. Compounds 1 and 5 exhibited significant antibacterial activity against carbapenems-resistant Pseudomonas aeruginosa and multidrug-resistant Enterococcus faecium with an minimum inhibitory concentration (MIC) value of 3.13 µg/ml respectively.