SYNTHESIS OF 2-O-α, 3-O-α, 3-O-β, AND 4-O-α-L-RHAMNOPYRANOSYL-D-GALACTOSE

Article abstract of DOI:10.1016/S0008-6215(00)80970-2

Condensation of benzyl 3-O-benzoyl-4,6-O-benzylidene-, benzyl 2-O-benzoyl-4,6-O-benzylidene- (2), and benzyl 2,3,6-tri-O-benzyl-β-D-galactopyranoside, separately, with tri-O-acetyl-α-L-rhamnopyranosyl bromide gave mainly α-linked disaccharide derivatives.An appreciable proportion of the β-linked disaccharide was also abtained from 2.An anomalous deacylation reaction was found for the (1-->3)-linked disaccharide, and the partially benzoylated products were isolated and characterised.The anomeric configuration of each disaccharide was established on the basis of J_C-1,H-1 values.The chemical shifts for the galactose moieties of the α and β-L-rhamnopyranosyl derivatives differed in a systematic way.