title: Synthesis of isoxazoles en route to semi-aromatized polyketides: dehydrogenation of benzonitrile oxide-para-quinone acetal cycloadducts.
abstract: A variety of highly functionalized polycyclic isoxazoles are prepared by a two-step protocol: (1) 1,3-dipolar cycloaddition of o,o'-disubstituted benzonitrile oxides to para-quinone mono-acetals, then (2) dehydrogenation. The cycloaddition proceeds in a regioselective manner, favouring the formation of the 4-acyl cycloadducts, which are suitable intermediates for the synthesis of semi-aromatized polycyclic targets derived from polyketide type-II biosynthesis.
authors.affiliation: Department of Chemistry, Tokyo Institute of Technology, O-okayama, Tokyo 152-8551, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Akiomi
authors.initials: A
authors.lastname: Takada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takikawa
authors.forename: Keisuke
authors.initials: K
authors.lastname: Suzuki
mesh_terms: D000080:Acetals / Q000737:chemistry*; D016227:Benzoquinones / Q000737:chemistry*; D006865:Hydrogenation; D007536:Isomerism; D007555:Isoxazoles / Q000138:chemical synthesis* / Q000737:chemistry*; D009570:Nitriles / Q000737:chemistry*; D061065:Polyketides / Q000737:chemistry*
chemical_list: D000080:Acetals; D016227:Benzoquinones; D007555:Isoxazoles; D009570:Nitriles; D061065:Polyketides; C004532:quinone; C014356:benzonitrile