Oleanane-type triterpenoid saponins from Xanthoceras sorbifolia Bunge.

Phytochemical analysis of the extract from the seed oil leavings of Xanthoceras sorbifolia Bunge led to the isolation of five new oleanane-type triterpeniod saponins, sorbifoliasides G-K (1-5). Their structures were elucidated on the basis of spectroscopic analysis and chemical derivatization. To our knowledge, compound 5 is the first example of a naturally occurring 3,28-O-bisdesmosic triterpenoid saponin with olefinic linkages at C12 and C15. The cytotoxicity of all compounds against ten selected human cancer cell lines was assayed.