title: Pentacyclic triterpenoid and saponins from Gambeya boukokoensis.
abstract: Chemical studies of the EtOAc extract of Gambeya boukokoensis Aubr. et Pellegr. stem bark led to the isolation of eight compounds. Three of them were elucidated as new compounds and designated as: gamboukokoensein A, 1alpha,2alpha,3beta,19alpha,23-pentahydroxyurs-12-en-28-oic acid; gamboukokoenside A, 2beta,3beta,6beta,28-tetrahydroxyolean-12-en-23-oic acid 23-O-alpha-L-arabinopyranosyl ester and gamboukokoenside B, 6beta,28-dihydroxy-3-oxoolean-12-en-23-oic acid 23-O-alpha-L-arabinopyranosyl ester. The other five compounds were known and identified as myrianthic acid, protobassic acid, oleanolic acid, erythrodiol and chondrillasterol. Their structures were elucidated on the basis of one and two dimensional NMR spectroscopic techniques, FABMS, ESMS and chemical evidence.
authors.affiliation: Department of Organic Chemistry, University of Yaounde-1, Faculty of Science, PO Box 812 Yaoundé, Cameroon. jeanwandji@yahoo.fr
authors.forename: Jean
authors.initials: J
authors.lastname: Wandji
authors.forename: François
authors.initials: F
authors.lastname: Tillequin
authors.forename: Dulcie A
authors.initials: DA
authors.lastname: Mulholland
authors.forename: Jovita Chi
authors.initials: JC
authors.lastname: Shirri
authors.forename: Nole
authors.initials: N
authors.lastname: Tsabang
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Seguin
authors.forename: Philippe
authors.initials: P
authors.lastname: Verite
authors.forename: Francine
authors.initials: F
authors.lastname: Libot
authors.forename: Z T
authors.initials: ZT
authors.lastname: Fomum
mesh_terms: D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D024301:Plant Bark / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D011083:Polycyclic Compounds / Q000737:chemistry* / Q000302:isolation & purification*; D012503:Saponins / Q000737:chemistry* / Q000302:isolation & purification*; D029632:Sapotaceae / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D011083:Polycyclic Compounds; D012503:Saponins; D014315:Triterpenes