Cytotoxic diterpenoids from Rabdosia lophanthoides var. gerardianus

Two new abietane diterpenoids, Gerardianin B (1) and Gerardianin C (2), one new lignan glycoside, Gerardianin D (3) and one new lupane-type triterpenoid, Gerardianol A (4), together with seven known abietane diterpenoids were isolated from the aerial parts of Rabdosia lophanthoides var. gerardianus. Their structures were determined by 1D and 2D NMR spectroscopic data. The cytotoxic activities of the nine diterpenoids were evaluated on human cancer cell lines. Compounds 6-11 exhibited significant cytotoxic activities against HepG2 cell lines with IC50 from 4.68 to 9.43 M and HCF-8 cell lines with IC50 from 9.12 to 13.53 M. (C) 2015 Published by Elsevier B.V.