Rosellichalasins A-H, cytotoxic cytochalasans from the endophytic fungus Rosellinia sp. Glinf021.

Eight new cytochalasans rosellichalasins A-H (1-8), as well as two new shunt metabolites rosellinins A (9) and B (10) before intramolecular Diels-Alder cycloaddition reaction in cytochalasan biosynthesis, along with nine known cytochalsans (11-19) were isolated from the endophytic fungus Rosellinia sp. Glinf021, which was derived from the medicinal plant Glycyrrhiza inflata. Their structures were characterized by extensive analysis of 1D and 2D NMR as well as HRESIMS spectra and quantum chemical ECD calculations. The cytotoxic activities of these compounds were evaluated against four human cancer cell lines including HCT116, MDA-MB-231, BGC823, and PANC-1 with IC50 values ranging from 0.5 to 58.2 µM.

New chlamydosporol derivatives from the endophytic fungus Pleosporales sp. Sigrf05 and their cytotoxic and antimicrobial activities.

Five new chlamydosporol derivatives, named pleospyrones A-E (1-5), together with one known congener (6), were isolated from the culture of the endophytic fungus Pleosporales sp. Sigrf05, obtained from the medicinal plant Siraitia grosvenorii. The structures of the new compounds were elucidated mainly by analysis of the HRESIMS, and (1D, 2D) NMR data, while ECD and optical rotation calculations were used to assign the absolute configurations. The plausible biosynthetic pathway of these compounds were proposed. The isolated compounds were evaluated for their cytotoxicity, antifungal and antibacterial activities. Compounds 1, and 4-6 were cytotoxic against the tested cancer cells with IC50 values of 1.26~47.5 µM. Compounds 1-3 showed moderate antifungal activities against Magnaporthe oryzae, while compound 5 displayed weak antibacterial activity.