Triterpenoid saponins from Dipsacus asper and their activities in vitro

Two new triterpenoid saponins 1 and 2, along with six known saponins 3-8, were isolated from the roots of Dipsacus asper. The structures of new compounds were established as 3-O-β-d-glucopyranosyl-(1 → 4)-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranoside (dipsacus saponin J, 1) and 3-O-α-l-arabinopyranosyl-hederagenin-28-O-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (dipsacus saponin K, 2). The structures were determined by extensive analysis of their spectroscopic data. Compounds 6 and 7 could significantly stimulate UMR106 cell proliferation and increase alkaline phosphatase activities in UMR106 cell at the concentration of 4 μM.