title: Computation-Assisted Structural Elucidation of Epoxyroussoeone and Epoxyroussoedione Isolated from Roussoella japanensis KT1651.
abstract: The structures of epoxyroussoenone (1) and epoxyroussoedione (3) isolated from a culture broth of Roussoella japanensis KT1651 were determined. Although NMR spectra provided insufficient structural information, computation of the theoretical chemical shifts with DFT EDF2/6-31G* enabled us to elucidate not only the planar structure, but also the relative configuration. Their ECD (electric circular dichroism) spectra suggested the absolute configurations, which were confirmed with time-dependent DFT calculations employing BHandHLYP/TZVP. The ECD calculations for other stereoisomers yielded obviously different spectral profiles, thus confirming the relative structures of 1 and 3.
authors.affiliation: †Faculty of Agriculture and Bioscience, Hirosaki University, 3-Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
authors.forename: Yuna
authors.initials: Y
authors.lastname: Honmura
authors.affiliation: †Faculty of Agriculture and Bioscience, Hirosaki University, 3-Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Takekawa
authors.affiliation: †Faculty of Agriculture and Bioscience, Hirosaki University, 3-Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: †Faculty of Agriculture and Bioscience, Hirosaki University, 3-Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
authors.forename: Hayato
authors.initials: H
authors.lastname: Maeda
authors.affiliation: ‡Graduate School of Integrated Arts and Sciences, Hiroshima University, 1-7-1, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nehira
authors.affiliation: §Wavefunction, Inc., 18401 Von Karman Avenue, Suite 370, Irvine, California 92612, United States.
authors.forename: Warren
authors.initials: W
authors.lastname: Hehre
authors.affiliation: †Faculty of Agriculture and Bioscience, Hirosaki University, 3-Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Hashimoto
mesh_terms: D001203:Ascomycota / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D007564:Japan; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism
chemical_list: D004852:Epoxy Compounds; C000602208:epoxyroussoedione; C000602207:epoxyroussoeone