title: Synthesis of pachastrissamine from phytosphingosine: a comparison of cyclic sulfate vs an epoxide intermediate in cyclization.
abstract: [reaction: see text] The syntheses of the cytotoxic natural product pachastrissamine and its unnatural 4-epi-congener were accomplished starting from a natural phytosphingosine. The relatively unstrained cyclic sulfate intermediate smoothly underwent the 5-endo cyclization to yield the 2,3,4-trisubstituted tetrahydrofuran ring system of pachastrissamine. The corresponding epoxy alcohol afforded the 4-epi-congener via a tosylate-mediated double inversion process.
authors.affiliation: College of Pharmacy, Seoul National University, San 56-1, Shilim, Kwanak, Seoul 151-742, Korea.
authors.forename: Taeho
authors.initials: T
authors.lastname: Lee
authors.forename: Sukjin
authors.initials: S
authors.lastname: Lee
authors.forename: Young Shin
authors.initials: YS
authors.lastname: Kwak
authors.forename: Deukjoon
authors.initials: D
authors.lastname: Kim
authors.forename: Sanghee
authors.initials: S
authors.lastname: Kim
mesh_terms: D003500:Cyclization; D004852:Epoxy Compounds / Q000737:chemistry*; D008956:Models, Chemical; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry*
chemical_list: D004852:Epoxy Compounds; D013431:Sulfates; C468594:pachastrissamine; C012491:phytosphingosine; D013110:Sphingosine