Question

The monosaccharides having anomeric carbon atom are

• A. geometrical isomers
• B. $\alpha$ -and $\beta$ -optical isomers
• C. having symmetrical carbon atoms
• D. None of the above

Answer 1

Answer: (B)

$C_1$ carbon of monosaccharides is called anomeric carbon. When the $-OH$ group attached with $C_1$ carbon is towards right, it is called $\alpha$ -form and when the $-OH$ group is towards left, it is called $\beta$ -form. Such pair of optical isomers which differ in the configuration only around anomeric carbon are called anomers.