Disaccharide A sugar formed from two

Disaccharide a sugar formed from two monosaccharides joined by a glycoside linkage. (22.6)... 

Disaccharide a sugar formed from two monosaccharides joined... 

Describe the process by which a disaccharide forms from two simple sugar molecules. 

Disaccharides, formed from two monosaccharides, are the simplest polysaccharides. The disaccharlde lactose, composed of galactose and glucose. Is the major sugar In milk the disaccharlde sucrose, composed of glucose and fructose. Is a principal product of plant photosynthesis and Is refined Into common table sugar (Figure 2-17). 

Sometimes two sugar molecules join up to form a disaccharide. One well-known disaccharide is called sucrose, C F On, formed from one molecule of glucose... 

The net result of all these competitive reactions is a possible mixture of normal and /3-glycosides and a possible mixture of two diastereo-isomeric orthoesters. In the course of the Konigs-Knorr procedure, water is usually formed from the reaction between hydrogen halide and silver oxide. The water formed, or deliberately employed, may take the part of the solvent alcohol, thus giving rise to products such as acidic orthoesters and normal tetra- and heptaacetates (for a disaccharide) of the sugars, and these compounds are subject to further changes, such as acyl migration. 

D-Glucose in various views (stick and space-filling) from the web. Disaccharides are formed when two monosaccharides are chemically bonded together. Sucrose, a common plant disaccharide is composed of the monosaccharides glucose and fructose. Lactose, milk sugar, is a disaccharide composed of glucose and the monosaccharide galactose. 

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