title: New cytotoxic oleanane saponins from the infructescences of Polyscias amplifolia from the Madagascar rainforest.
abstract: Bioassay-guided fractionation of an ethanolic extract of the infructescences of Polyscias amplifolia resulted in the isolation of two new oleanolic acid saponins, polyfoliolides A (1) and B (2), in addition to the two known saponins 3-O-beta-D-galactopyranosyloleanolic acid (3) and 3-O-beta-D-galactopyranosyl-(1-->4)-beta-D-galactopyranosyloleanolic acid (4). The structures of the two new compounds were established as 3-O-beta- D-galactopyranosyl-(1-->4)-beta-D-xylopyranosyloleanolic acid (1) and 3-O-beta-D-galactopyranosyl-(1-->4)-alpha-L-arabinopyranosyloleanolic acid (2) on the basis of extensive 1D and 2D NMR spectroscopic data interpretation and chemical conversions. All the isolated compounds showed weak cytotoxicity against A2780 human ovarian cancer cell line, with IC50 values in the range 6.7 to 10.8 microg/mL.
authors.affiliation: Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: V S Prakash
authors.initials: VS
authors.lastname: Chaturvedula
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Schilling
authors.forename: James S
authors.initials: JS
authors.lastname: Miller
authors.forename: Rabodo
authors.initials: R
authors.lastname: Andriantsiferana
authors.forename: Vincent E
authors.initials: VE
authors.lastname: Rasamison
authors.forename: David G
authors.initials: DG
authors.lastname: Kingston
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D027481:Araliaceae; D005260:Female; D006801:Humans; D020128:Inhibitory Concentration 50; D008270:Madagascar; D008519:Medicine, Traditional; D010051:Ovarian Neoplasms / Q000188:drug therapy; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D012503:Saponins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D010936:Plant Extracts; D012503:Saponins