title: Triterpene saponins in the defensive secretion of a chrysomelid beetle, Platyphora ligata.
abstract: The secretion of the defensive glands of adults of the chrysomelid beetle Platyphora ligata from Panama has been shown to contain, besides chlorogenic acid (1) and a mixture of phosphatidylcholines, two new oleanane triterpene saponins, named ligatosides A and B. Their structures were established as 3-O-beta-D-glucuronopyranosyl-16alpha,23-dihydroxyoleanol ic acid-28-O-2-(3,4-dimethoxybenzoyl)-beta-D-glucopyranoside (2) and 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-16a lpha, 23-dihydroxyoleanolic acid-28-O-2-(3, 4-dimethoxybenzoyl)-beta-D-glucopyranoside (3), respectively, by a combination of extensive 1D and 2D NMR methods (COSY, HMQC, HMBC, and TOCSY) and FABMS. This is the first report of triterpene saponins in the defensive secretion of an insect.
authors.affiliation: Laboratory of Bio-organic Chemistry, Department of Organic Chemistry, CP 160/07, Brussels, Belgium.
authors.forename: V
authors.initials: V
authors.lastname: Plasman
authors.forename: J C
authors.initials: JC
authors.lastname: Braekman
authors.forename: D
authors.initials: D
authors.lastname: Daloze
authors.forename: M
authors.initials: M
authors.lastname: Luhmer
authors.forename: D
authors.initials: D
authors.lastname: Windsor
authors.forename: J M
authors.initials: JM
authors.lastname: Pasteels
mesh_terms: D000818:Animals; D002726:Chlorogenic Acid / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D001517:Coleoptera / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010176:Panama; D010713:Phosphatidylcholines / Q000032:analysis; D012503:Saponins / Q000032:analysis / Q000302:isolation & purification*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet; D014315:Triterpenes / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D010713:Phosphatidylcholines; D012503:Saponins; D014315:Triterpenes; C410927:ligatoside A; C410928:ligatoside B; D002726:Chlorogenic Acid