title: Three new triterpenoid saponins from Ixeris sonchifolia and their cytotoxic activity.
abstract: Bioassay-guided fractionation of an active n-BuOH extract of the whole plant of Ixeris sonchifolia, using a cytotoxicity assay, resulted in the isolation of three new triterpenoid saponins, ixeris saponins A (1), B (2), and C (3). On the basis of chemical evidence and extensive spectral studies, their structures were established as echinocystic acid 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha- L-arabinopyranoside (1), 3-O-[bis[beta-D-glucopyranosyl(1-->2 and 1-->3)-alpha-L-arabinopyranosyl]]echinocystic acid 28-O-beta-D-glucopyranosyl ester (2), and 3- O-[beta-D-glucopyranosyl(1-->3)-beta- D-glucopyranosyl(1-->3)-alpha-L-arabinopyranosyl]-16alpha, 23-dihydroxyolean-12-ene 28-O-beta-D-glucopyranosyl ester (3). Compounds 2 and 3 showed significant cytotoxicity against cancer cell lines A375, L929, and HeLa with IC50 values ranging from 8.83 microM to 15.83 microM, while compound 1 was inactive against these three cell lines.
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Xi-Zhi
authors.initials: XZ
authors.lastname: Feng
authors.forename: Mei
authors.initials: M
authors.lastname: Dong
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Gao
authors.forename: Sui-Xu
authors.initials: SX
authors.lastname: Xu
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D019659:Asteraceae; D045744:Cell Line, Tumor / Q000187:drug effects; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D020128:Inhibitory Concentration 50; D008517:Phytotherapy; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D014315:Triterpenes