Chapter 16, Problem 18P

Interpretation Introduction

Interpretation:

The epimers of D-glucose have to be stated.

Concept introduction:

The compound with molecular formula ${\text{C}}_{\text{6}}{\text{H}}_{\text{12}}{\text{O}}_{\text{6}}$ is the sugar called as glucose.  It is stored as a polymer.  The D-isomer of glucose is known to be D-glucose that is one of the sixteen aldohexose stereoisomers.

The pair of stereoisomers is known as epimer. The two isomers in one pair have different configuration at only one stereo genic centre.

Answer to Problem 18P

The epimer of D-glucose is D-galactose.

Explanation of Solution

The epimer of D-glucose is D-galactose because the configuration of D-galactose is only different at the fourth carbon atom as shown in Figure $1$.

Figure $1$

Therefore, D-galactose is also known as $\text{C-4}$ epimer of D-glucose.

Conclusion

The epimer of D-glucose was identified.