title: Total synthesis of an immunosuppressive glycolipid, (2S,3S,4R)-1-O- (alpha-d-galactosyl)-2- tetracosanoylamino-1,3,4-nonanetriol.
abstract: [reaction: see text] A practical and efficient total synthesis of (2S,3S,4R)-1-O-(alpha-d-galactosyl)-2-tetracosanoylamino-1,3,4-nonanetriol, OCH 1b, a potential therapeutic candidate for Th1-mediated autoimmune diseases, is described. The synthesis incorporates direct alkylation onto epoxide 5 and stereospecific halide ion catalyzed alpha-glycosidation reaction. A key intermediate 10 was obtained in only eight steps and 37% overall yield from commercially available d-arabitol 2, and the total synthesis of 1b was accomplished in 12 steps and 19% overall yield. This method will enable the synthesis of a variety of phytosphingolipids, especially that with the shorter sphingosine side chain than 1a, in a highly stereoselective manner.
authors.affiliation: Daiichi Suntory Biomedical Research Co., Ltd., 1-1-1, Wakayamadai, Shimamoto-cho, Mishima-gun, Osaka 618-8513, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Murata
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Toba
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nakanishi
authors.forename: Bitoku
authors.initials: B
authors.lastname: Takahashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamamura
authors.forename: Sachiko
authors.initials: S
authors.lastname: Miyake
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Annoura
mesh_terms: D006028:Glycosphingolipids / Q000138:chemical synthesis*; D007166:Immunosuppressive Agents / Q000138:chemical synthesis*; D008968:Molecular Conformation
chemical_list: D006028:Glycosphingolipids; D007166:Immunosuppressive Agents