Lanostane‐Type Triterpenes from Poria Cocos peels and Their Alpha‐glucosidase Inhibitory Activity

From the methanol extract of the Poria Cocos peels, two novel tetracyclic triterpenoid (1‐2) and six known triterpenenes (3‐8) were isolated. The structures of the new compounds were determined to be (20R)‐16α,24,31‐trihydroxy‐3,4‐seco‐lanosta‐4(28),7,9(11)‐triene‐3,21‐dioic acid 3‐oate (1), (20R)‐3β,23‐dihydroxy‐ lanosta‐7,9(11),24(25)‐triene‐21‐oic acid (2). Their structures were elucidated by analyses of the HR‐ESI‐MS, 1D and 2D NMR spectra. All isolated triterpeoids were evaluated for their α‐glucosidase inhibitory activities in vitro. Compound 2 and 6 exhibited moderate α‐glucosidase inhibitory activity with the IC50 values of 132.1±3.4 μM and 271.0 ± 5.2 μM, respectively.