Anti-cancerous triterpenoid saponins from Lecaniodiscus cupanioides

From the ethanol extract of the stem of Lecaniodiscus cupanioides Planch, two known compounds 1 and 2 were isolated and identified as triterpenoid saponins 3-O-[α-L-arabinofuranosyl- (1→3)-α-L-rhamnopyranosyl- (1→2)-α-L-arabinopyranosyl-]-hederagenin and 3-O- [α-L-arabinopyranosyl- (1→3)-α-L-rhamnopyranosyl (1→2)-α-L-arabinopyranosyl-]-hederagenin. The structures were established by physicochemical and spectroscopic investigations (MS and NMR) as well as comparison of literature data. The compound 1 exhibited anticancer activity against human colon carcinoma H-116, human lung carcinoma A-549 and human lung carcinoma HT-29 cell lines with IC₅₀ 5.0, 2.5 and 2.5μg/ml respectively and compound 2 exhibited similar activities with IC₅₀5.0, 5.0 and 2.5μg/ml respectively. This suggests that the isolated triterpenoid saponins may be considered as potential anticancer leads for further studies.