Question

Given, the structure of $D-(+)$-glucose as The structure of $L-(+)$ -glucose is

• A.
• B.
• C.
• D.

Answer 1

Answer: (B)

$D$ and $L$ before the name of any compound commonly indicates the relative configuration. For assigning the configuration of monosaccharides it is the lowest asymmetric carbon atom, which is compared to glyceraldehyde. For glucose, if —$OH$ on the lowest asymmetric carbon is on the right side. Then, it is assigned $D$-configuration and if $OH$ is on the left side then it is assigned $L$-configuration. Both $D$ and $L$ configuration are mirror images of each other.