title: Synthetic studies toward GKK1032s, novel antibiotic antitumor agents: enantioselective synthesis of the fully elaborated tricyclic core via an intramolecular Diels-Alder cycloaddition.
abstract: An enantioselective synthesis of the fully elaborated tricyclic decahydrofluorene core (ABC-ring system) of GKK1032s, novel antimicrobial and antitumor agents, has been accomplished for the first time by employing a highly diastereoselective intramolecular Diels-Alder (IMDA) reaction. The key substrate for the IMDA reaction was efficiently prepared through (i) an intermolecular Diels-Alder reaction between a siloxydiene and an optically active enone derived from D-mannitol to construct the appropriately functionalized C-ring and (ii) CuCl-promoted Stille coupling of an (E)-vinyl iodide and a vinylstannane to install the requisite triene side chain as the crucial steps.
authors.affiliation: Department of Electronic Chemistry, Tokyo Institute of Technology, Nagatsuta, Yokohama 226-8502, Japan.
authors.forename: Moriteru
authors.initials: M
authors.lastname: Asano
authors.forename: Munenori
authors.initials: M
authors.lastname: Inoue
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Watanabe
authors.forename: Hideki
authors.initials: H
authors.lastname: Abe
authors.forename: Tadashi
authors.initials: T
authors.lastname: Katoh
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000138:chemical synthesis*; D002625:Chemistry, Organic / Q000379:methods*; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000903:Antibiotics, Antineoplastic; C479319:GKK1032A-2; D006576:Heterocyclic Compounds, 4 or More Rings