Part [1] Formation of an N-phenylthiourea CHs PEPTIDE PEPTIDE PEPTIDE CH, CHs R. 'R phenyl isothiocyanate нн N-phenylthiourea 1-2 Addition of the amino group of the N-terminal amino acid to phenyl isothiocyanate followed by proton transfer forms an N-phenylthiourea. Part [2] Formation of the N-terminal amino acid and N-phenylthiohydantoin (PTH) н-А HÖ PEPTIDE several CeHs. steps PEPTIDE -H* N. Н-А -R CeHs CeHs CHs 'R N-phenylthiourea thiazolinone N-phenylthiohydantoin (PTH) HạN- PEPTIDE 3 Nucleophilic addition of the S atom to the amide carbonyl forms a five-membered ring. 4 Loss of the amino group forms two products-a thiazolinone ring and a peptide chain that contains one fewer amino acid than the original peptide. 5 The thiazolinone rearranges by a multistep pathway to form an N-phenylthiohydantoin (PTH) that contains the original amino acid.

Part [1] Formation of an N-phenylthiourea CHs PEPTIDE PEPTIDE PEPTIDE CH, CHs R. 'R phenyl isothiocyanate нн N-phenylthiourea 1-2 Addition of the amino group of the N-terminal amino acid to phenyl isothiocyanate followed by proton transfer forms an N-phenylthiourea. Part [2] Formation of the N-terminal amino acid and N-phenylthiohydantoin (PTH) н-А HÖ PEPTIDE several CeHs. steps PEPTIDE -H* N. Н-А -R CeHs CeHs CHs 'R N-phenylthiourea thiazolinone N-phenylthiohydantoin (PTH) HạN- PEPTIDE 3 Nucleophilic addition of the S atom to the amide carbonyl forms a five-membered ring. 4 Loss of the amino group forms two products-a thiazolinone ring and a peptide chain that contains one fewer amino acid than the original peptide. 5 The thiazolinone rearranges by a multistep pathway to form an N-phenylthiohydantoin (PTH) that contains the original amino acid.

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter26: Biomolecules: Amino Acids, Peptides, And Proteins

Section26.SE: Something Extra

Problem 54AP

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