Chapter 21, Problem 5A

Interpretation Introduction

Interpretation:

General formula of α-amino acid must be sketched indicating the α-amino carbon atom. Portion of the structure must be circled which is common to all α-amino acids.

Concept Introduction:

α-Amino acids are a class of compounds which contains at least one carboxylic acid group and at least one amino group at α-carbon (carbon next to COOH).

Explanation of Solution

A general structure of α-amino acid is given. R can be different side chains. α-carbon is indicated with arrow. The common portion of all α-amino acid is shown in the circle which contains a carbon (α-carbon) directly bonded with one NH₂ and one COOH group.