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Dependence of 13C chemical shifts on the spatial interaction of protons, and its application in structural and conformational studies of oligo- and poly-saccharides

✍ Scribed by Nikolay K. Kochetkov; Oleg S. Chizhov; Alexander S. Shashkov

Publisher: Elsevier Science
Year: 1984
Tongue: English
Weight: 914 KB
Volume: 133
Category: Article
ISSN: 0008-6215
DOI: 10.1016/0008-6215(84)85196-4

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✦ Synopsis

Regularities in the variation of chemical shifts and the glycosidation effects in the 13C-n.m.r. spectra of disaccharides were found to depend on the configuration at the anomeric centre of the glycosidating pyranose, and the absolute configuration of both pyranoses moieties. These empirical regularities are explained in terms of the spatial proton-proton interactions within the statistically averaged, or preferred, conformation near the glycosidic linkage. The applicability of these effects for the determination of the anomeric and absolute configuration and the sequence of pyranose residues in oligo-and poly-saccharides is discussed. The conformational properties of glycosidic linkages in disaccharides and disaccharide fragments of oligo-and poly-saccharides are compared on the basis of 13C-n.m.r. data.

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