Terpenoids from the tuber of Cremastra appendiculata

Abstract

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), ( − )-ent-12β-hydroxykaur-16-en-19-oic acid, 19-O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopyranoside (2), and (+)-24,24-dimethyl-25,32-cyclo-5α-lanosta-9(11)-en-3β-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 3.18 μM, but 1 and 2 were inactive (IC₅₀>10 μg/ml).

Keywords:

• Cremastra appendiculata
• Orchidaceae
• terpenoids
• cytotoxic activities

Acknowledgements

Financial support is from the New Century Excellent Talent supporting program of the Chinese Ministry of Education (NCET), the NSF (Grant no. 20372084 and 20432030), and the national ‘973’ program of China (Grant no. 2004CB13518906), and the Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT, Grant no. IRT0514).