Chapter 26.12, Problem 20P

Interpretation Introduction

Interpretation:

The structure of the PTH derivative isolated in the second Edman cycle of the tetrapeptide $\text{Val-Phe-Gly-Ala}$ is to be given.

Concept Introduction:

Edman degradation uses phenyl isothiocyanate to cleave the bond between the N-terminal amino acid and the rest of the peptide chain.

Anhydrous conditions ensure that other amide bonds are not cleaved.