title: Synthesis of a core disaccharide from the Streptococcus pneumoniae type 23F capsular polysaccharide antigen.
abstract: The synthesis of methyl α-l-rhamnopyranosyl-(1→2)-β-d-galactopyranoside and methyl α-l-rhamnopyranosyl-(1→2)-3-(glycer-2-yl-phosphate)-β-d-galactopyranoside disaccharides from the Streptococcuspneumoniae type 23F capsular polysaccharide is reported. A simple protecting group strategy was followed using commercially available monosaccharides and phosphorylating reagents. H-Phosphonate and phosphoramidite coupling chemistries were explored for introducing the phosphodiester. Hydrazine hydrate was found to be a mild and efficient deacetylating agent, which was required to avoid phosphate migration during the deprotection of the phosphodiester functionalized disaccharide.
authors.affiliation: Department of Chemistry, 80 St. George Str. Toronto, ON, Canada.
authors.forename: Somnath
authors.initials: S
authors.lastname: Dasgupta
authors.forename: Mark
authors.initials: M
authors.lastname: Nitz
mesh_terms: D016667:Bacterial Capsules / Q000737:chemistry*; D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D013296:Streptococcus pneumoniae / Q000737:chemistry*
chemical_list: D004187:Disaccharides; D011135:Polysaccharides, Bacterial