Oligosaccharides anomeric configuration

Hodosi, G. Kovac, P., Glycosylation via locked anomeric configuration stereospecific synthesis of oligosaccharides containing the beta-D-mannopyranosyl and beta-L-rhamnopyranosyl linkage. Carbohydr. Res. 1998, 308, 63-75. 

Full interpretation of data of this type must await further understanding of the specificities of the enzymes involved, of the nature of the residual oligosaccharide, and of the problem of possible heterogeneity discussed earlier. An advantage of enzymic methods is that the anomeric configuration may be revealed. 

We have shown that the selective activation of the TOPCAT donors is possible with AgOTf in the presence of MOP acceptors. In a typical iterative process, one can use O-benzyl TOPCAT donors with partially ether or ester O-pro tec ted MOP acceptors for the synthesis of di-, tri-, or oligosaccharides with predetermined anomeric configurations in the major... 

The sequence and anomeric configuration of the oligosaccharide chain was determined by step-wise hydrolysis with specific glycosidases. The conditions of incubation for hydrolysis are the same as those previously described (12). For the hydroly-... 

At the outset of an examination of an oligosaccharide, a well resolved one-dimensional (ID) NMR spectrum provides a guide to anomeric configuration, and may also reveal unsuspected features, such as noncarbohydrate substituents. As an example (Fig. 1), the H-NMR spectrum of the oligoglycosylalditol from M. avium serovar 25 shows characteristic anomeric protons, especially for the j3-gluco configuration of the penultimate glucosyluronic residue.14... 

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