title: Antibacterial diterpenes and their fatty acid conjugates from rice leaves.
abstract: Six structurally oryzalide-related compounds, oryzadione (1), 2, 3, 4, 5 and 6, were isolated from a neutral fraction of the extract of healthy leaves using a bacterial leaf blight-resistant cultivar of a rice plant, "Norin-27", as a group of antimicrobial substances. Their structures were determined by spectroscopic studies to be kaurane analogues and kaurane analogues conjugated with fatty acids, i.e., 1: ent-15,16-epoxy-kauran-2,3-dione (enol form: ent-15,16-epoxy-2-hydroxy-kauran-1-en-3-one), 2: ent-15,16-epoxy-3beta-hydroxy-kauran-2-one, 3: ent-15,16-epoxy-3-oxa-kauran-2-one, 4: ent-15,16-epoxy-3beta-myristoyloxy-kauran-2-one, 5: ent-15,16-epoxy-3alpha-palmitoyloxy-kauran-2-one, and 6: ent-15,16-epoxy-2beta-palmitoyloxy-kauran-2-one.
authors.affiliation: School of Agriculture, University of Ibaraki, Ami, Ibaraki 300-0393, Japan. ykono@mx.ibaraki.ac.jp
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Kono
authors.forename: Aya
authors.initials: A
authors.lastname: Kojima
authors.forename: Rieko
authors.initials: R
authors.lastname: Nagai
authors.forename: Manabu
authors.initials: M
authors.lastname: Watanabe
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kawashima
authors.forename: Tsugu
authors.initials: T
authors.lastname: Onizawa
authors.forename: Tohru
authors.initials: T
authors.lastname: Teraoka
authors.forename: Minoru
authors.initials: M
authors.lastname: Watanab
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Koshino
authors.forename: Jun
authors.initials: J
authors.lastname: Uzawa
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Akira
authors.initials: A
authors.lastname: Sakurai
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D045786:Diterpenes, Kaurane / Q000737:chemistry* / Q000494:pharmacology; D005227:Fatty Acids / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D012275:Oryza / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D045786:Diterpenes, Kaurane; D005227:Fatty Acids; D010936:Plant Extracts