Triterpenoids from the husks of Xanthoceras sorbifolia Bunge

A new triterpenoid saponin, 3-O-[(3-O-alpha-l-arabinofuranosyl-2-O-beta-d-galactopyranosyl)-beta-d-glucuronopyranosyl]-21,22-di-O-angeloyl-R1-barrigenol (1), together with four known triterpenoids, have been isolated from the husks of Xanthoceras sorbifolia Bunge. Their structures were elucidated based on chemical and spectral analysis. Among them, 1 was found to have activity of inhibiting the proliferation of six human tumour cell lines (IC50 10-40 mug/ml).