title: alpha-Glucosidase inhibitory pentacyclic triterpenes from the stem bark of Fagara tessmannii (Rutaceae).
abstract: In addition to fatty acids, a mixture of sterols (beta-sitosterol, stigmasterol, campesterol and stigmastanol), lupeol, arctigenin methylether, sesamin, vanillic acid (1), 2,6-dimethoxy-1,4-benzoquinone (2), betulinic acid and two pentacyclic triterpene acetates were isolated from Fagara tessmannii Engl. They were identified as 3beta-acetoxy-16beta-hydroxybetulinic acid (3a) and 3beta,16beta-diacetoxybetulinic acid (3b), and their structures were established using 1 and 2D NMR spectra and by comparison with published data. Two derivatives of the compounds were prepared. Some isolated compounds were evaluated for their antifungal and antibacterial activities. Compounds 1 and 3a showed significant inhibition of alpha-glucosidase.
authors.affiliation: Department of Chemistry, University of Douala, P.O. Box 24157, Douala, Cameroon.
authors.forename: Luc Meva'a
authors.initials: LM
authors.lastname: Mbaze
authors.forename: Herve Martial P
authors.initials: HM
authors.lastname: Poumale
authors.forename: Jean Duplex
authors.initials: JD
authors.lastname: Wansi
authors.forename: Jean Alexandre
authors.initials: JA
authors.lastname: Lado
authors.forename: Shamsun Nahar
authors.initials: SN
authors.lastname: Khan
authors.forename: Muhammad Choudhary
authors.initials: MC
authors.lastname: Iqbal
authors.forename: Bonaventure Tchaleu
authors.initials: BT
authors.lastname: Ngadjui
authors.forename: Hartmut
authors.initials: H
authors.lastname: Laatsch
mesh_terms: D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010840:Phytosterols / Q000737:chemistry / Q000302:isolation & purification; D018547:Plant Stems / Q000737:chemistry*; D027821:Rutaceae / Q000737:chemistry*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000520:alpha-Glucosidases / Q000302:isolation & purification*
chemical_list: D004791:Enzyme Inhibitors; D010840:Phytosterols; D014315:Triterpenes; D000520:alpha-Glucosidases