A new triterpenoid from the stems of Kadsura coccinea with antiproliferative activity

A series of schiartane C₂₉ nortriterpenoids with 5/5/7/6/5 membered consecutive rings (1‒5) with an unique schinortriterpenoid skeleton including a new, kadcoccilactone V (1), together with four known ones (2‒5) and three known triterpenoids (6‒8) were identified from stems of Kadsura coccinea (Lem.) A. C. Smith. The structures of 1 and known compounds were elucidated by interpretation of 1D and 2D NMR, and HR-ESI-MS data as well as comparing those data in the literature. All the isolated compounds were examined for cytotoxic effects against six human cancer cell lines [(HCT-15 (colon), NUGC-3 (stomach), NCI-H23 (lung), ACHN (renal), PC-3 (prostate), and MDA-MB-231 (breast)]. Among them, compound 6 showed potent cytotoxicity against NCI-H23 (GI₅₀ 1.28 µM) and NUGC-3 (GI₅₀ 1.28 µM), and significantly inhibited on PC-3, MDA-MB-231, ACHN, HCT-15 with GI₅₀ values around 2.33 to 2.67 µM.