Question

Glycosidic linkage is an:
(A)- Amide linkage
(B)- Ester linkage
(C)- Ether linkage
(D)- Acetyl linkage

Answer 1

Hint: It is an organic divalent functional group. It contains oxygen. This oxygen is linked to two alkyl groups which may or may not be similar. These linkages are used to attach a carbohydrate to another functional group, usually another carbohydrate.

Complete step by step solution:
A glycosidic bond is formed between the hemiacetal group of saccharide and the hydroxyl group of another compound like an alcohol. This is a covalent bond which links carbohydrate (sugar) to other compounds which may or may not be a carbohydrate.
This bond is formed as a result of condensation between an alcohol of one group to the anomeric carbon of the sugar. A water molecule is released and O- linkage is formed between the two molecules.
In ethers there is an O atom which is linked to two alkyl groups. For example in diethyl ether, an O atom is present linking two ethyl groups.
So, glycosidic linkage contains an ether linkage.
Hence, the answer to the given question is option (C).

Additional Information:
S- glycosidic bond is formed when the O atom is replaced by a S atom, also known as thioglycosides. In the same way when N atom replaces the O atom then N-glycosidic bond is formed. These are known as glycosylamines.

Note:
Glycosidic linkage is not only formed by oxygen atoms, it is formed by nitrogen and sulphur also.
Ethers are divalent functional groups. They are non-polar in nature. A type of ethers known as crown ethers are used in nucleophilic reactions as they can trap the metal ion and lead to the better formation of a nucleophile.