New depsidones and isoindolinones from the mangrove endophytic fungus Meyerozyma guilliermondii (HZ-Y₂) isolated from the South China Sea

• Senhua Chen,
• Zhaoming Liu,
• Yayue Liu,
• Yongjun Lu,
• Lei He and
• Zhigang She

Beilstein J. Org. Chem. 2015, 11, 1187–1193, doi:10.3762/bjoc.11.133

• exhibited strong α-glucosidase inhibitory activity with IC50 values ranging from 2.1 to 13.3 μM. Moreover, kinetic studies of compounds 2 and 6 showed that both of them were noncompetitive inhibitors of α-glucosidase. Keywords: endophytic fungus; depsidone; α-glucosidase inhibitory activity; isoindolinone

• aromatic rings (I) and (III) should be linked by ether and an ester bridge, revealing a depsidone skeleton with a seven-membered ring (II). Thus, the structure of 1 was revealed as a new depsidone belonging to the same family compound of the botryorhodines A–D [6], named botryorhodine E. Botryorhodine F (2