Furostanol saponins with inhibitory action against COX-2 production from Tupistra chinensis rhizomes

Two furostanol saponins were obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes, a folk medicine of Shennongjia Forest District of Hubei Province. Their structures were determined as (25S)-26-O-(β-d-glucopyranosyl)-furost-1β, 3β, 22α, 26-tetrol-3-O-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (1) and (25R)-26-O-(β-d-glucopyranosyl)-furost-1β, 3β 22α, 26-tetrol 3-O-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (2), on basis of chemical and spectroscopic evidences. 1 and 2 displayed marked inhibitory action towards COX-2 production in macrophages of the rat abdomen induced by LPS at 20 μg/mL.