Pyranose Sugars chemical bonding

Carbohydrate polymers derive from nature s capacity for converting carbohydrate molecules into polyacetals. Figure 1 shows how chemical bonding between a pyranose sugar s C-1 and with one of several different hydroxyls can occur in four different ways. In addition, the configuration of the bond at C-1 may be axial or equatorial (a or 3) leading to steric isomers. Thus 2 glucopyranose... 

Polysaccharides prepared from 1,4-anhydro sugars contain both pyranose (6-membered) and fiiranose (5-membered) rings in the main chain l2). The presence of both structures was established by hydrolysis which showed that either of the chemically equivalent, C-l-O-bonds may be broken during polymerization ... 

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