Sesquiterpenes from Tinospora sinensis and their chemotaxonomic significance

Chemical investigation of the Tinospora sinensis led to the isolation of a new cadinane sesquiterpene (1) and twelve known sesquiterpenes (2-13). The structures of these compounds were deduced using a suite of comprehensive spectroscopic techniques including NMR, MS etc., and the absolute configuration of 1 was established through a combination of TDDFT calculations and chemical methods. Compound 1 demonstrated mild cytotoxicity against MDA-MB-231 cell line, with an inhibition rate of 46.8% and 54.2% at 50 mu mol/L and 100 mu mol/L, respectively. Compounds 1, 5-13 were reported to exist in the Menispermaceae family for the first time. Furthermore, the chemotaxonomic significance of the isolates is also discussed.