New schiartane-type triterpene from Kadsura heteroclita and their cytotoxic activities.

One new schiartane-type triterpene, heteroclitalactone N (1), and four known compounds (2-5), seco-coccinic acid F, dihydroguaiaretic acid, schizanrin F, and kadsuralignan B were isolated from the stems of Kadsura heteroclita. Their structures were determined by the combination of spectroscopic and chemical methods, including 1D-, 2D-NMR, and CD spectra as well as by comparing with the NMR data reported in the literature. The cytotoxic activities of all isolated compounds were evaluated on three human cancer cell lines. Compound 3 exhibited moderate to weak cytotoxic activities on three human cancer cell lines, OVCAR, HT-29, and A-549, with IC50 values ranging from 16.2 to 36.4 microM.