Chapter 18, Problem 18.24QP

Interpretation Introduction

Interpretation:

The $\text{D-}$ and $\text{L-isomers}$ of valine has to be drawn. And also the isomer of valine that is found in nature has to be given.

Concept Introduction:

One of the classifications to represent both isomers of an amino acid is $\text{D-}$ and $\text{L-}$ configuration of amino acid. In $\text{D-}$ and $\text{L-}$ configuration of the amino acid, most oxidized group (carboxylate group) must be represented at the top while alkyl chain at the bottom. $\text{D-}$ configuration is given to the amino acid whose $-{\text{NH}}_3^{+}$ group is on the right side while $\text{L-}$ configuration is given to the amino acid whose $-{\text{NH}}_3^{+}$ group is on the left side.

The general structures of $\text{D-}$ configuration and $\text{L-}$ configuration of $\text{α-amino acid}$ are as follow: