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

(a)a' carbon of glucose and 'a' carbon of fructose
(b)a' carbon of glucose and 'e' carbon of fructose
(c)a' carbon of glucose and 'b' carbon of fructose
(d)f' carbon of glucose and 'f' carbon of fructose

Options

A. a' carbon of glucose and 'a' carbon of fructose
B. a' carbon of glucose and 'e' carbon of fructose
C. a' carbon of glucose and 'b' carbon of fructose
D. f' carbon of glucose and 'f' carbon of fructose

Answer

C

Explanation

Carbon adjacent of oxygen atom in the cyclic structure of glucose or fructose is known as anomeric carbon. As shown in the structure above 'a' and 'b' are present at adjacent to oxygen atom. Both carbons differ in configuration of the hydroxyl group.