alpha-Furanones, secondary metabolites from the fungus Cephalotrichum microsporum and their antibacterial activities

摘要

Cephalotrichum microsporum is a fungus isolated from the rhizosphere soil of Panax notoginseng. Four secondary metabolites (three new and one known alpha-furanones) of this fungus cultivated on a sterilized moistened-rice medium were isolated using an EtOAc extract. The structures of these compounds were determined by extensive spectroscopic data analysis using 1D- and 2D-NMR, ECD, and HRESIMS. In the antibacterial bioassay, compounds 2 and 3 displayed moderate inhibitory effects on S. aureus and B. subtilis with an inhibition rate of more than 50% at a concentration of 50.0 mu g/mL. Additionally, compounds 1 - 4 displayed weak antibacterial effects on MR Staphylococcus aureus.