title: Anthraquinones of the roots of Pentas micrantha.
abstract: Pentas micrantha is used in the East African indigenous medicine to treat malaria. In the first investigation of this plant, the crude methanol root extract showed moderate antiplasmodial activity against the W2- (3.37 μg/mL) and D6-strains (4.00 μg/mL) of Plasmodium falciparum and low cytotoxicity (>450 μg/mL, MCF-7 cell line). Chromatographic separation of the extract yielded nine anthraquinones, of which 5,6-dihydroxylucidin-11-O-methyl ether is new. Isolation of a munjistin derivative from the genus Pentas is reported here for the first time. The isolated constituents were identified by NMR and mass spectrometric techniques and showed low antiplasmodial activities.
authors.affiliation: Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya.
authors.forename: Milkyas
authors.initials: M
authors.lastname: Endale
authors.forename: Annabel
authors.initials: A
authors.lastname: Ekberg
authors.forename: John Patrick
authors.initials: JP
authors.lastname: Alao
authors.forename: Hoseah M
authors.initials: HM
authors.lastname: Akala
authors.forename: Albert
authors.initials: A
authors.lastname: Ndakala
authors.forename: Per
authors.initials: P
authors.lastname: Sunnerhagen
authors.forename: Máté
authors.initials: M
authors.lastname: Erdélyi
authors.forename: Abiy
authors.initials: A
authors.lastname: Yenesew
mesh_terms: D000880:Anthraquinones / Q000302:isolation & purification / Q000494:pharmacology*; D000962:Antimalarials / Q000302:isolation & purification / Q000494:pharmacology*; D004351:Drug Resistance; D009682:Magnetic Resonance Spectroscopy; D008288:Malaria / Q000188:drug therapy; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry*; D010963:Plasmodium falciparum / Q000187:drug effects / Q000254:growth & development; D019666:Rubiaceae / Q000737:chemistry*
chemical_list: D000880:Anthraquinones; D000962:Antimalarials; D010936:Plant Extracts