title: Quinovic acid glycosides from Mitragyna stipulosa--first examples of natural inhibitors of snake venom phosphodiesterase I.
abstract: Phytochemical investigations on the non-alkaloidal extracts of Mitragyna stipulosa bark has led to the isolation of a series of triterpenoids mainly consisting of quinovic acid ([structure: see text]) and its glycoside derivatives [structure: see text] and [structure: see text]. The other constituents isolated include alpha-amyrin, 3beta-acetyl ursolic acid and a mixture of oleanolic and ursolic acid and beta-sitosterol glucopyranoside. Their structures were identified by spectral and chemical studies and compounds [structure: see text] and [structure: see text] were, respectively, identified as quinovic acid 3-O-[beta-D-glucopyranoside] (quinovin glycoside C) and quinovic acid 3-O-[beta-D-quinovopyranoside]-27-O-[beta-D-glucopyranosyl] ester. Compounds [structure: see text] and [structure: see text] showed significant inhibitory activity against snake venom phosphodiesterase I.
authors.affiliation: HEJ Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan.
authors.forename: Naheed
authors.initials: N
authors.lastname: Fatima
authors.forename: Leon Azefack
authors.initials: LA
authors.lastname: Tapondjou
authors.forename: David
authors.initials: D
authors.lastname: Lontsi
authors.forename: B L
authors.initials: BL
authors.lastname: Sondengam
authors.lastname: Atta-Ur-Rahman
authors.forename: M Iqbal
authors.initials: MI
authors.lastname: Choudhary
mesh_terms: D002163:Cameroon; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D032065:Mitragyna / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009828:Oleanolic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000031:analogs & derivatives; D010726:Phosphodiesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D012910:Snake Venoms / Q000037:antagonists & inhibitors*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D005960:Glucosides; D010726:Phosphodiesterase Inhibitors; D010936:Plant Extracts; D012910:Snake Venoms; D014315:Triterpenes; C472607:quinovic acid 3-O-quinovopyranoside-27-O-glucopyranosyl ester; C472606:quinovin glycoside C; D009828:Oleanolic Acid; C472605:quinovic acid; C036380:beta-amyrin