Two new triterpenoids from the stems of Celastrus orbiculatus Thunb

Two new triterpenoids, named as 3 beta-(E)-p-caffeoylnepeticin (1) and 3 beta-(E)-3,4-dimethoxycinnamate-20(S)dammarenediol II (2), along with three known compounds 3, 4 and 5 were isolated from the stems of Celastrus orbiculatus Thunb. The structures of these compounds were elucidated by spectroscopic methods including IR, 1D and 2D NMR as well as by high-resolution mass spectrometric analysis. The anti-inflammatory activities and the cytotoxic effects were evaluated on lipopolysaccharide induced nitric oxide production in RAW 264.7 cells and two tumor cell lines (MCF-7 and A2780s), respectively. Results showed that compounds 1 and 3 exhibited weak anti-inflammatory activity with the IC50 value of 18.50 and 10.51 mu M respectively, while all compounds were inactive in both cell lines (IC50 > 20 mu M).