PREPARATION OF OLIGOSACCHARIDES WITH β-D-MANNOPYRANOSYL AND 2-AZIDO-2-DEOXY-β-D-MANNOPYRANOSYL RESIDUES BY INVERSION AT C-2 AFTER COUPLING

Article abstract of DOI:10.1016/0008-6215(89)84070-4

Di- and tri-saccharides with a 2,4,6-tri-O-acetyl-3-O-benzyl-β-D-glucopyranosyl unit were prepared by coupling 1,2,4,6-tetra-O-acetyl-3-O-benzyl-β-D-glucopyranose (1) to suitably, partially benzylated, acceptor sugar derivatives.Deacetylation followed by acetalation gave 3-O-benzyl-4,6-O-benzylidene-β-D-glucopyranosyl derivatives which were treated with N,N'-sulfuryldi-imidazole.The resulting 2-imidazylate group was displaced easily with inversion by benzoate or azide, leading to β-D-mannopyranosyl or 2-azido-2-deoxy-β-D-mannopyranosyl derivatives, respectively.Protected derivatives of β-D-Manp-(1->4)-D-Glc, β-D-Manp-(1->4)-D-Man,β-D-Manp-(1->4)-β-D-Manp-(1->4)-D-Glc, 2-azido-2-deoxy-β-D-Manp-(1->4)-D-Glc, and 2-azido-2-deoxy-β-D-Manp-(1->6)-D-Glc were prepared thus.