Monosaccharides Haworth projection formula

Two sugars can link to each other by losing water from OHs to form disaccharides. Figure 4.6 shows the Haworth projection formulas of four important disaccharides sucrose, lactose, maltose, and cellobiose, which all have the same molecular formulas, C12H22011. Sucrose and lactose are the most abundant and most important disaccharides of natural origin. Maltose and cellobiose are repeating units of polymeric starch and cellulose, respectively. Disaccharides may hydrolyze to form two monosaccharide molecules. 

The Haworth projection formulas are neater ways of writing the ring forms shown in the equilibria above and yet preserving the configuration shown at each chiral carbon. It is not difficult to translate the open-chain structure for a monosaccharide into the Haworth ring structure. 

CONFORMATIONAL STRUCTURES Although Haworth projection formulas are often used to represent carbohydrate structure, they are oversimplifications. Bond angle analysis and X-ray analysis demonstrate that conformational formulas are more accurate representations of monosaccharide structure (Figure 7.10). Conformational structures are more accurate because they illustrate the puckered nature of sugar rings. 

CYCLIC MONOSACCHARIDES HEMIACETALS AND HEMIKETALS Haworth Projection Formulas... 

Drawing the Haworth Projection of a Monosaccharide from the Structural Formula... 

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