Analytical Pyrolysis of Polymeric Carbohydrates

Monosaccharides. Polysaccharides, and General Aspects of their Pvroivsis. 

The monosaccharides with the same stereochemistry as L-glyceraldehyde at the most distant asymmetric carbon will form the L-series of aldoses. 

The configurations of monosaccharides are described by several types of formulas. As an example, the following formulas are shown for a-D-glucopyranose structural, Haworth, modified Fischer, and Fischer. In Fischer formulas the -H or -OH groups are above or below the plane formed by the hemiacetal bonds and the carbon chain (-H bonds are shown shorter). 

Because poiysaccharides are natural macromolecules occurring in all living organisms, the structure of some polysaccharides can be much more complex, as they are not made only from simple monosaccharides. In the composition of natural polymeric carbohydrates, a wide variety of sugars are found. Among these, the most common are pentoses and hexoses. The structural formulas of three common pentoses are shown below. They frequently form cyclic structures with five-member rings (furanoses). 

The structural formulas of several common hexoses are shown below. 

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