title: Divergent synthesis of trans-fused polycyclic ethers by a convergent oxiranyl anion strategy.
abstract: Octacyclic polyethers that correspond to the CDEFGHIJ-ring system of yessotoxin as well as G- and/or I-ring-modified analogues were synthesized in a divergent manner, starting from a common intermediate, using an [X + 2 + Y]-type convergent method. Reaction of a triflate with the oxiranyl anion generated from an epoxy sulfone, followed by ring expansion, allowed for the incorporation of medium-sized ring ethers into the key intermediate. Subsequent acetal formation and reductive etherification afforded various octacycles containing seven- and eight-membered ether rings.
authors.affiliation: Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Sakai
authors.forename: Ai
authors.initials: A
authors.lastname: Sugimoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tatematsu
authors.forename: Yuji
authors.initials: Y
authors.lastname: Mori
mesh_terms: D060326:Chemistry Techniques, Synthetic; D004988:Ethers, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry*; D005027:Ethylene Oxide / Q000737:chemistry*; D008968:Molecular Conformation; D008978:Mollusk Venoms; D035964:Oxocins / Q000737:chemistry
chemical_list: D004988:Ethers, Cyclic; D008978:Mollusk Venoms; D035964:Oxocins; D005027:Ethylene Oxide; C066632:yessotoxin