Triterpenoid saponins with anti-myocardial ischemia activity from the whole plants of Clematis tangutica.

Four new triterpenoid saponins named clematangosides A-D (1-4) along with six known saponins (5-10) were isolated from the whole plants of Clematis tangutica. Their structures were determined by extensive spectral analysis and chemical evidences. All saponins were evaluated for their protective effects in hypoxia-induced myocardial injury model. Compounds 2-4, 6, and 10 exhibited anti-myocardial ischemia activities with ED50 values in the range of 75.77-127.22 µM.