摘要
Uncaria rhynchophylla(Gouteng)is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China.In this study,the ethyl acetate(EtOAc)part of U.rhynchophylla was revealed with protein tyrosine phosphatase 1B(PTP1B)inhibitory activity.Subsequent investigation on the EtOAc part yielded one new triterpenoid,3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid(1)and four known ones,3β,6β,19α-trihydroxyurs-12-en-28-oic acid(2),2-oxopomolic acid(3),3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid(4)and sumaresinolic acid(5).The structure of compound 1 was determined by extensive HRESIMS,IR,1D and 2D NMR spectroscopic analyses.Two ursane-type triterpenoids(2 and 3)showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7μM.The enzyme kinetic study suggested that compounds 2 and 3 were mixtype inhibitors on PTP1B with Ki values of 15.6 and 132.5μM.This investigation manifests the antidiabetic potency of U.rhynchophylla with triterpenoids as the active constituents.
基金
the Yunnan Wanren Project(YNWR-QNBJ-2018-061)
the Yunnan Science Fund for Excellent Young Scholars(2019FI017)
the Reserve Talents of Young and Middle-aged Academic and Technical Leaders in Yunnan Province(2018HB067)
the National Natural Science Foundation of China(81573322).
