There are some following reactions:
Oxidation
The aldehyde functional group is oxidized to a carboxyl group. For example, glucose is oxidized to gluconic acid by benedict's solution or Fehlings solution [both are alkaline solutions of copper ions, cu2+ ions are reduced to Cu+ ions.
Reduction
The aldehyde group is reduced to the hydroxyl or alcohol group in the presence of an enzyme or hydrogen and a metal catalyst.
Esterification:
The alcohol (-OH) group on the sugar can react with phosphoric acid (H3PO4) to give phosphate esters. Remember that alcohols react with carboxylic acids to yield esters and water. The formation of a phosphate ester is known as phosphorylation. An example of this is the formation of glucose in the body.
Formation of glycosides
The hydrogen (H) of the –OH group on carbon atom 1 of sugar, such as glucose, may be replaced by other radicals to form compounds called glycosides.
Glycosides from glucose are called glucosides e.g., alpha-methylglucosides and beta-methylglucoside.
Glycosides formed from galactose are called glycosides. Most of the complex galactosides are of great pharmacological importance. An example is dioxin, which is extensively used in medicine because of its effect on the heart.
Oxidation
The aldehyde functional group is oxidized to a carboxyl group. For example, glucose is oxidized to gluconic acid by benedict's solution or Fehlings solution [both are alkaline solutions of copper ions, cu2+ ions are reduced to Cu+ ions.
Reduction
The aldehyde group is reduced to the hydroxyl or alcohol group in the presence of an enzyme or hydrogen and a metal catalyst.
Esterification:
The alcohol (-OH) group on the sugar can react with phosphoric acid (H3PO4) to give phosphate esters. Remember that alcohols react with carboxylic acids to yield esters and water. The formation of a phosphate ester is known as phosphorylation. An example of this is the formation of glucose in the body.
Formation of glycosides
The hydrogen (H) of the –OH group on carbon atom 1 of sugar, such as glucose, may be replaced by other radicals to form compounds called glycosides.
Glycosides from glucose are called glucosides e.g., alpha-methylglucosides and beta-methylglucoside.
Glycosides formed from galactose are called glycosides. Most of the complex galactosides are of great pharmacological importance. An example is dioxin, which is extensively used in medicine because of its effect on the heart.
