REACTION INVOLVING BOTH GLYCOSIDIC AND ALCOHOLIC OH GROUPS Reaction with acetic anhydride (Esterification). The glycosidic and alcoholic OH groups of monosaccharides and disaccharides
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چکیده
Reaction with alcohol. The glycosidic OH group of mutarotating sugars react with alcohols to form αand βglycosides or acetals. Thus, glucose forms glucosides and fructose forms fructosides. The glucosides, or glycosides in general, do not exhibit mutarotation as the aldehyde group in them is converted to the acetal group. A number of glycosides occur in nature, e.g., phlorhizin (glucose + phloretin) in rose bark ; digitonin (4 galactose + xylose + digitogenin) in foxglove leaves; amygdalin (2 glucose + 2 mandelonitril) from bitter almonds and saponin (sugar + sapogenin) from soapwort. They are useful as medicaments.
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