title: Three new naphthoquinone derivatives from Diospyros maritima Blume.
abstract: Three new naphthoquinone derivatives, 6-(1-ethoxyethyl)plumbagin (16), ethylidene-3,3'-biplumbagin (17), and ethylidene-3,6'-biplumbagin (18), were isolated, in addition to six known naphthoquinones, isozeylanone (10), 3,3'-biplumbagin (11), chitranone (12), methylene-3,3'-biplumbagin (13), 2,3-epoxyplumbagin (14), and 3,8'-biplumbagin (15), from the fruits of Diospyros maritima Blume (Ebenaceae). The structures of the new compounds were established by spectroscopic methods. The eight naphthoquinones 11-18 were examined for ichthyotoxic activity and germination inhibitory activity. The quinones 11, 12, and 14-16 showed strong ichthyotoxic activity and the quinone 14 mild germination inhibitory activity.
authors.affiliation: College of Science, University of the Ryukyus, Nishihara, Okinawa, Japan. matuhiga@sci.u-ryukyu.ac.jp
authors.forename: Matsutake
authors.initials: M
authors.lastname: Higa
authors.forename: Nobue
authors.initials: N
authors.lastname: Noha
authors.forename: Hiroto
authors.initials: H
authors.lastname: Yokaryo
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Ogihara
authors.forename: Seiichi
authors.initials: S
authors.lastname: Yogi
mesh_terms: D000818:Animals; D002855:Chromatography, Thin Layer; D029788:Diospyros / Q000737:chemistry*; D005399:Fishes / Q000502:physiology; D005638:Fruit / Q000737:chemistry; D018525:Germination / Q000187:drug effects; D018545:Lactuca / Q000187:drug effects / Q000254:growth & development; D009682:Magnetic Resonance Spectroscopy; D009285:Naphthoquinones / Q000737:chemistry* / Q000494:pharmacology / Q000633:toxicity
chemical_list: D009285:Naphthoquinones