title: Stereoselective synthesis of trans-fused 7,6,6,7-membered tetracyclic ether, corresponding to the EFGH-ring of gambierol and the BCDE-ring of gambieric acids.
abstract: Stereoselective synthesis of a trans-fused 7,6,6,7-membered tetracyclic ether, corresponding to the EFGH-ring of gambierol and the BCDE-ring of gambieric acids, was efficiently accomplished via a two-directional approach. The key reactions were SmI(2)-induced double cyclization for construction of the F- and H-rings and SmI(2)-induced cyclization followed by ring expansion for construction of the E-ring.
authors.affiliation: Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Saito
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nakata
mesh_terms: D003500:Cyclization; D004988:Ethers, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D004988:Ethers, Cyclic