Synthesis of Ureidopeptides and Peptidyl Ureas Employing Bsmoc Chemistry

This work describes the utility of Bsmoc group in the synthesis of ureidopeptides and peptidyl ureas. The reaction of isocyanates derived from Bsmoc-α-amino acids with amino acid ester has yielded the ureidopeptides in good yields. The isocyanates were obtained by subjecting Bsmoc-amino acid azides to Curtius rearrangement. Bsmoc protected ureidopeptides have been isolated as solids and characterized by 1H NMR, 13C NMR and mass spectrum.