Terpenoids from the tuber of Cremastra appendiculata

Two new terpenoids including a cadinane sesquiterpene (1), and an ent-kaurane diterpene diglycoside (2), together with a known triterpene containing 32 carbons (3), have been isolated from the ethanolic extract of Cremastra appendiculata. Their structures were established by the spectroscopic methods including the IR, MS, 1D-, and 2D-NMR experiments as (-)-cadin-4,10(15)-dien-11-oic acid (1), (2)-ent-12 beta-hydroxykaur-16-en-19- oic acid, 19-O-beta-D-xylopyranosyl-(1 -> 6)-O-beta-D-glucopyranoside (2), and (+)-24,24-dimethyl- 25,32-cyclo-5 alpha-lanosta-9(11)-en-3 beta-ol (3). Compounds 1-3 were evaluated against several human cancer cell lines. Compound 3 showed in vitro-selective cytotoxicity against human breast cancer cell lines (MCF-7) with an IC50 of 3.18mM, but 1 and 2 were inactive (IC50 > 10 mu g/ml).