Secondary Metabolites with α-Glucosidase Inhibitory Activity from the Mangrove Fungus Mycosphaerella sp. SYSU-DZG01

摘要

Four new metabolites, asperchalasine I ( 1 ), dibefurin B ( 2 ) and two epicoccine derivatives ( 3 and 4 ), together with seven known compounds ( 5 – 11 ) were isolated from a mangrove fungus Mycosphaerella sp. SYSU-DZG01. The structures of compounds 1 – 4 were established from extensive spectroscopic data and HRESIMS analysis. The absolute configuration of 1 was deduced by comparison of ECD data with that of a known structure. The stereostructures of 2 – 4 were further confirmed by single-crystal X-ray diffraction. Compounds 1 , 8 and 9 exhibited significant α-glucosidase inhibitory activity with IC 50 values of 17.1, 26.7 and 15.7 μM, respectively. Compounds 1 , 4 , 6 and 8 showed antioxidant activity by scavenging DPPH· with EC 50 values ranging from 16.3 to 85.8 μM.