title: Two new cytotoxic naphthoquinones from Mendoncia cowanii from the rainforest of Madagascar.
abstract: Bioassay-guided fractionation of the root and stem extracts of Mendoncia cowanii led to the isolation of two new and two known naphthoquinones. The structures of the new compounds, avicequinones D and E (1 and 2), were determined using 1D and 2D NMR spectroscopy and by chemical conversion of compound 1 to 2. The new compounds were active in the A2780 human ovarian cancer cell line with IC50 values of 7.4 - 50 microM, respectively, and 1, 3, and 4 were subsequently found to be weakly active in an assay for inhibition of the kinase Akt.
authors.affiliation: Department of Chemistry, M/C 0212, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
authors.forename: Russell B
authors.initials: RB
authors.lastname: Williams
authors.forename: Andrew
authors.initials: A
authors.lastname: Norris
authors.forename: James S
authors.initials: JS
authors.lastname: Miller
authors.forename: L Jeremie
authors.initials: LJ
authors.lastname: Razafitsalama
authors.forename: Rabodo
authors.initials: R
authors.lastname: Andriantsiferana
authors.forename: Vincent E
authors.initials: VE
authors.lastname: Rasamison
authors.forename: David G
authors.initials: DG
authors.lastname: Kingston
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D045744:Cell Line, Tumor / Q000187:drug effects; D005260:Female; D006801:Humans; D020128:Inhibitory Concentration 50; D008270:Madagascar; D019684:Magnoliopsida; D008519:Medicine, Traditional; D009285:Naphthoquinones / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000473:pathology; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D018547:Plant Stems; D014197:Trees
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D009285:Naphthoquinones; D010936:Plant Extracts