Chapter 25, Problem 78PP

Interpretation Introduction

Interpretation:

Four possible peptides that will be formed when L-phenylalanine and L-alanine is treated with DCC need to be drawn.

Concept introduction:

Peptides are a chain of amino acids that are linked together by amide bond.  The key steps involved in peptide synthesis is,

• Installation of appropriate protecting groups in amino acid
• Coupling of protected amino acids using DCC
• Deprotection of protecting groups to give the final peptide.

Please remember that DCC is not a regioselective catalyst.  Hence when DCC is used to couple two different amino acids, four different peptides are formed.