Cytotoxic triterpenoid glycosides from leaves of Cyclocarya paliurus.

Three previously undescribed dammarane triterpenoid glycosides (1-3) along with five known analogues (4-8) were isolated from the leaves of Cyclocarya paliurus. Their structures and configurations were determined on the basis of comprehensive spectroscopic analyses, chemical hydrolysis and DFT GIAO (13)C NMR calculation. All the isolates were evaluated cytotoxic activities against seven human cancer cell lines (MCF-7, PC-3, Du145, NCI-H1975, PC-9, SKVO3 and HepG2). Moreover, compound 4 showed a wide spectrum of cytotoxicity against human cancer cells with IC50 values ranging from 11.31 to 29.51 microM.