Formation of Glycosides from Monosaccharides

PROBLEM 16.10 Write an equation for the reaction of D-mannose with Fehling s reagent (Cu ) to give D-mannonic acid. 

Aldoses are oxidized by aqueous nitric acid to dicarboxylic acids called aldaric acids. 

Because monosaccharides exist as cyclic hemiacetals, they can react with one equivalent of an alcohol to form acetals. An example is the reaction of j8-D-glucose with methanol. 

Note that only the —OH on the anomeric carbon is replaced by an —OR group. Such acetals are called glycosides, and the bond from the anomeric carbon to the OR group is called the glycosidic bond. Glycosides are named from the corresponding 

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