Antibacterial diterpenes and their fatty acid conjugates from rice leaves.
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.
Kono
Yoshiki
Y
School of Agriculture, University of Ibaraki, Ami, Ibaraki 300-0393, Japan. ykono@mx.ibaraki.ac.jp
Kojima
Aya
A
Nagai
Rieko
R
Watanabe
Manabu
M
Kawashima
Takahiro
T
Onizawa
Tsugu
T
Teraoka
Tohru
T
Watanab
Minoru
M
Koshino
Hiroyuki
H
Uzawa
Jun
J
Suzuki
Yoshikatsu
Y
Sakurai
Akira
A
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
D000900:Anti-Bacterial Agents; D045786:Diterpenes, Kaurane; D005227:Fatty Acids; D010936:Plant Extracts