Three new ursane-type triterpenes from the leaves of Rehmannia glutinosa

Three new ursane-type triterpenes, glutinosalactone A – C ( 1 – 3 ), were isolated from the 50% aqueous acetone extract of the leaves of Rehmannia glutinosa . Their structures were elucidated on the basis of spectral analysis (IR, NMR and MS spectroscopy). The cytotoxic effects of compounds 1 – 3 against three human cancer cell lines (MCF-7, MG63 and HepG2) were also evaluated. Compound 3 showed cytotoxic activities with IC 50 values of 8.35–39.25 μM.