Peptides Containing Aminophosphonic Acids. I. Reactivity of α-Aminobenzylphosphonic Acid

The chemical reactivity of α-aminobenzylphosphonic acid was investigated in order to survey the methods for incorporating aminophosphonic acids into a peptide chain. The investigation revealed that i) a dipeptide analog linked with a phosphonamide bond could be produced by the reaction of C-protected amino acid with the N-protected aminophosphonomonochloridate, and that ii) amino groups of the aminophosphonic acid possessed a reactivity similar to those of amino acids, and were capable of coupling with N-protected amino acids by means of dicyclohexylcarbodiimide.