20. Carboxylic Acid Derivatives:NAS
Nucleophilic Acyl Substitution
Edman's degradation of a peptide forms thiazoline which can undergo rearrangement in dilute acid to phenylthiohydantoin (PTH) amino acid. Propose a mechanism for the rearrangement of the thiazoline shown below. (Hint: Thioesters react readily with nucleophiles.)