Glycosides Disaccharide Polysaccharide

Sections Disaccharides are carbohydrates in which two monosaccharides are 25.14-25.15 joined by a glycoside bond. Polysaccharides have many monosaccharide units connected through glycosidic linkages. Complete hydrolysis of disaccharides and polysaccharides cleaves the glycoside bonds, yielding the free monosaccharide components. 

Glucose is by far the most abundant monosaccharide it occurs free in fruits, plants, honey, in the blood of animals, and combined in many glycosides, disaccharides, and polysaccharides. The structure and properties of glucose will be considered in greater detail than those of the other monosaccharides, not only because of its importance, but because much of what can be said about glucose also can be said about the other monosaccharides. 

Glycosides are obtained by conversion of the cyclic semiacetal form of aldoses and ketoses to an acetal. We will focus on the metal complexes and esters of the following glycosides alkyl pyranosides, alkyl furanosides, non-reducing disaccharides, polysaccharides, and Anally the nucleosides as a member of the group of iV-glycosides. 

Although the glycosidic bonds of uronic acid residues are usually more resistant to acid hydrolysis than those of neutral polysaccharides,218 these linkages in heparin are more readily cleavable then those between the hexosamine and the uronic acid residues. Disaccharides obtained by exhaustive hydrolysis of heparin with 0.5 MHC1 at 80° contained hexu-... 

Monosaccharides (simple sugars) containing an aldehyde group are called aldoses and those with a keto group are called ketoses. Disaccharides, oligosaccharides, and polysaccharides consist of monosaccharides linked by glycosidic bonds. 

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