title: 1,2-Diacetals in synthesis: total synthesis of a glycosylphosphatidylinositol anchor of Trypanosoma brucei.
abstract: A full account on a total synthesis of GPI anchor 1 employing butanediacetal (BDA) groups and a chiral bis(dihydropyran) is presented. The reactivity of selenium and thio glycosides was tuned by the use of BDA groups. This allowed the assembly of an appropriately protected GPI anchor precursor 2 in just six steps from the six building blocks 5-10 including only one protecting group manipulation. myo-Inositol was desymmetrised with the bis(dihydropyran) derivative 15 and appropriately protected to give inositol acceptor 21 in nine steps and 17% overall yield. The use of common starting materials and BDA-protections give efficient access to building blocks 5, 6, 7 and 8. A new and improved synthesis of the glucosamine donor 28 is included. In summary, a highly convergent and efficient synthesis of GPI anchor 1, which is clearly adaptable to other GPI anchors, has been reported.
authors.affiliation: Department of Chemistry, University of Cambridge, UK.
authors.forename: D K
authors.initials: DK
authors.lastname: Baeschlin
authors.forename: A R
authors.initials: AR
authors.lastname: Chaperon
authors.forename: L G
authors.initials: LG
authors.lastname: Green
authors.forename: M G
authors.initials: MG
authors.lastname: Hahn
authors.forename: S J
authors.initials: SJ
authors.lastname: Ince
authors.forename: S V
authors.initials: SV
authors.lastname: Ley
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002621:Chemistry / Q000379:methods; D005944:Glucosamine / Q000737:chemistry; D017261:Glycosylphosphatidylinositols / Q000138:chemical synthesis*; D007294:Inositol / Q000737:chemistry; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis; D014346:Trypanosoma brucei brucei / Q000737:chemistry*
chemical_list: D017261:Glycosylphosphatidylinositols; D009844:Oligosaccharides; D007294:Inositol; D005944:Glucosamine