Two new oleanane-type pentacyclic triterpenoid saponins from the husks of Xanthoceras sorbifolia Bunge

Two new triterpenoid saponins (1, 2) and a known saponin (3) were isolated from the husks of Xanthoceras sorbifolia Bunge., and their structures were elucidated as 3-O-β-D-glucopyranosyl(1 → 6)-angeloyl(1 → 2)]-β-D-glucopyranosyl-28-O-α-L-rhamnopyranosyl(1 → 2)-β-D-glucopyranosyl(1 → 6)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (1), 3-O-β-D-glucopyranosyl-28-O-β-D-glucopyranosyl(1 → 2)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (2), and 3-O-β-D-glucopyranosyl-28-O-α-L-rhamnopyranosyl(1 → 2)]-β-D-glucopyranosyl-21β,22α-dihydroxyl-olean-12-ene (3), on the basis of the spectral analysis of NMR and chemical methods. Cytotoxic assay indicated that none of them showed obvious inhibitory effect on the proliferation of two human tumor cell lines.