title: Efficient synthesis of 3, 6-dideoxy-beta-D-arabino-hexopyranosyl-terminated LacdiNac glycan chains of the Trichinella spiralis parasite.
abstract: The synthesis of a linear trisaccharide epitope of the Trichinella spiralis N-linked glycan, in a form amenable to glycoconjugate formation, is reported. The trisaccharide contains the synthetically challenging LacdiNAc [beta-GalpNAc(1-->4)-beta-GlcpNAc] element, as well as a terminal 3,6-dideoxy-beta-D-arabino-hexopyranose (tyvelose) residue. An orthogonal protection strategy is described, which permits the protection and manipulation of three amino groups present in the disaccharide beta-GalNAc(1-->4)-beta-GlcNAc and the tether used to prepare neoglycoconjugates. The beta-linked dideoxyhexose was generated in excellent yield by the introduction of the dideoxyhexose unit as a beta-D-ribo-hexopyranoside (paratose) followed by an oxidation-reduction sequence to generate the beta-D-arabino configuration in high diastereomeric excess. The required dideoxyhexose donor was synthesized in a series of high-yielding steps from glucose utilizing the p-methoxyphenyl glycoside.
authors.affiliation: Department of Chemistry, The University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Nitz
authors.forename: D R
authors.initials: DR
authors.lastname: Bundle
mesh_terms: D000606:Amino Sugars / Q000737:chemistry; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D002240:Carbohydrate Sequence; D000939:Epitopes; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009005:Monosaccharides / Q000737:chemistry; D009844:Oligosaccharides / Q000138:chemical synthesis*; D017160:Trichinella spiralis / Q000737:chemistry*
chemical_list: D000606:Amino Sugars; D000911:Antibodies, Monoclonal; D000939:Epitopes; D009005:Monosaccharides; D009844:Oligosaccharides