Glycosidic linkage rotations about

For some linkages, at least, it is possible to detect a substantial influence on the rotation about the glycosidic bond from the exo anomeric effect this evidence is from coupling constants (74T1933 80CJC631) and... 

Interactions of aqueous electrolytes with nonionic polysaccharides play an essential role in Investigations of plant cell wall polysaccharides, where Isolation and fractionation procedures are commonly based on different degrees of solubility in particular electrolytes. This is especially true of the beta-1,4-linked pentosans and hexosans which are the primary backbone structures of most of the cell wall polysaccharides not Infrequently solubility is the basis of identification as well. The beta-1,4-linked hexosans are a special subset which, because of constraints on the freedom of rotation about the bonds of the glycosidic linkage, tend to be less soluble than the pentosans or the hexosans with less constrained linkages. 

The rationale for the correct setting of current knowledge about the shape of polysaccharides in solution is based on three factors the correlation between primary structure (i.e., the chemical identity of the carbohydrates polymerized in the chain), intrinsic conformational features dictated by the rotational equilibria (often the major contributions are due to the rotation about the glycosidic linkages) and the interaction with the other mo-... 

Cellulose is a homopolymer of D-anhydroglucopyranose monomeric units connected through P-(l - 4 )-glycosidic linkages (Fig. 1). As illustrated, every other monomeric unit is rotated by approximately 180° about the long axis of the cellulose chain compared with its two neighboring monomeric units. Because of this, cellobiose is, in the strictest sense, properly considered the repeat unit... 

Lemieux, R. U., and S. Koto The Conformational Properties of Glycosidic Linkages. Tetrahedron 30, 1933 (1974) Bailey, W. F., and E. L. Eliel Conformational Analysis. XXIX. 2-Substituted and 2,2-Disubstituted 1,3-Dioxanes. The Generalized and Reverse Anomeric Effects. J. Amer. Chem. Soc. 96, 1798 (1974) Anet, F. A. L., and I. Yavari Generalized Anomeric Effect and Barrier to Internal Rotation about the Oxygen-Methylene Bond in Chloromethyl Ether. J. Amer. Chem. Soc. 99, 6752 (1977). 

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