title: Biologically active ibogan and vallesamine derivatives from Tabernaemontana divaricata.
abstract: Six new indole alkaloids, viz., (3S)-3-cyanocoronaridine (2), (3S)-3-cyanoisovoacangine (3), conolobine A (5), conolobine B (6), conolidine (7), and (3R/3S)-3-ethoxyvoacangine (8), in addition to 36 known ones, were obtained from the stem-bark extract of the Malayan Tabernaemontana divaricata. The structures were determined by NMR and MS analysis. The CN-substituted alkaloids showed appreciable cytotoxicity towards the KB human oral epidermoid carcinoma cell-line.
authors.affiliation: Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia. tskam@um.edu.my
authors.forename: Toh-Seok
authors.initials: TS
authors.lastname: Kam
authors.forename: Huey-Shen
authors.initials: HS
authors.lastname: Pang
authors.forename: Yeun-Mun
authors.initials: YM
authors.lastname: Choo
authors.forename: Kanki
authors.initials: K
authors.lastname: Komiyama
mesh_terms: D045744:Cell Line, Tumor; D006801:Humans; D007050:Ibogaine / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity*; D026121:Indole Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity; D024301:Plant Bark; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity; D018547:Plant Stems; D030014:Tabernaemontana
chemical_list: D026121:Indole Alkaloids; D010936:Plant Extracts; D007050:Ibogaine