Question

Structure of a disaccharide formed by glucose and fructose is given below. Identify anomeric carbon atoms in monosaccharide units.

• A. ${}^{\prime }{f}^{\prime }$ carbon of glucose and $‘f^{\prime }$ carbon of fructose.
• B. $‘a^{\prime }$ carbon of glucose and $‘a^{\prime }$ carbon of fructose.
• C. $‘a^{\prime }$ carbon of glucose and $‘e^{\prime }$ carbon of fructose.
• D. $‘a^{\prime }$ carbon of glucose and $‘b^{\prime }$ carbon of fructose.

Answer 1

The correct option is D $‘a^{\prime }$ carbon of glucose and $‘b^{\prime }$ carbon of fructose.

Anomeric carbon is at $C-1$ of a cyclic glucose and at $C-2$ of a cyclic fructose. It is adjacent to the oxygen atom of a cyclic structure in both the cases.

In the given structure of disaccharide, the anomeric carbon is $“a”$ in case of glucose and it is $“b”$ in case of fructose.

So, the correct answer is option (C).