title: A concise enantioselective synthesis of a key A-ring synthon for 1 alpha-hydroxyvitamin D3 compounds.
abstract: [figure: see text] This report describes a concise enantioselective synthesis of the A-ring synthon for the synthesis of 1 alpha-hydroxyvitamin D3 compounds. The synthesis involves two notable transformations: (I) stereoselective construction of the enol triflate from the vinyl ketone by Michael addition of Ph2P(O)Li followed by in situ triflation of the resulting enolate and (II) palladium-catalyzed Heck type cyclization of the enol triflate.
authors: Faculty of Pharmaceutical Sciences, Nagasaki University, Nagasaki 852, Japan.
authors: H
authors: H
authors: Hiyamizu
authors: H
authors: H
authors: Ooi
authors: Y
authors: Y
authors: Inomoto
authors: T
authors: T
authors: Esumi
authors: Y
authors: Y
authors: Iwabuchi
authors: S
authors: S
authors: Hatakeyama
mesh_terms: D002117:Calcitriol / Q000031:analogs & derivatives*; D006887:Hydroxycholecalciferols / Q000138:chemical synthesis*; D013237:Stereoisomerism
chemical_list: D006887:Hydroxycholecalciferols; D002117:Calcitriol