Structure elucidation of new oleanane‐type glycosides from three species of Acanthophyllum

From the roots of three species of Acanthophyllum (Caryophyllaceae), two new gypsogenic acid glycosides, 1 and 2, were isolated, 1 from A. sordidum and A. lilacinum, 2 from A. elatius and A. lilacinum, together with three known saponins, glandulosides B and C, and SAPO50. The structures of 1 and 2 were established mainly by 2D NMR techniques as 23-O-β-D-galactopyranosylgypsogenic acid-28-O-β-D-glucopyranosyl-(13)-[β-D-glucopyranosyl-(16)]-β-D-galactopyranoside (1) and gypsogenic acid-28-O-β-D-glucopyranosyl-(13)-[β-D-glucopyranosyl-(16)]-β-D-galactopyranoside (2). The cytotoxicity of several of these saponins was evaluated against two human colon cancer cell lines (HT-29 and HCT 116). Copyright © 2010 John Wiley & Sons, Ltd.