Oligosaccharides, Polysaccharides and Related Compounds

Publisher Summary The more complex saccharides, that is, those containing two or more sugar residues joined by glycosidic linkages, are termed oligosaccharides. Oligosaccharides containing more than ten sugar residues are usually classified separately as polysaccharides. In this chapter, nomenclature, separation and isolation, determination of constitution, synthesis, properties, and typical reactions of oligosaccharides, polysaccharides, and related compounds are discussed. The primary spotlight revolves around disaccharides and related compounds, trisaccharides containing one constituent sugar, two different constituent sugars, and three different constituent sugars as well as their functional derivatives. Tetrasaccharides and oligosaccharides from human milk are also covered in this chapter. The classical examples of complex polysaccharides are composed of one sugar unit only, examples being starch, cellulose, and glycogen, all being built up of glucose units. Technically important derivatives of cellulose such as cellulose nitrate and of starch such as glycogen (liver starch) have immense industrial and physiological significance. This chapter also provides a brief account of the several natural products that are related to the oligosaccharides: the teichoic acids, polymers of glycerol or ribitol phosphates, the glycoproteins such as egg albumin, and the glycolipids such as gangliosides found in brain.