Diphenylphosphorazide is used in many reactions such as peptide coupling and 1,3-dipolar cycloaddition. Diphenylphosphorazidate has also been used in the preparation of amino acid copolymers.
Wolff, O., Waldvogel, S.R.: Synthesis, 8, 1303 (2004); Yang, J. Z., Wang, M., Ottenbrite, R.M.: J. Bioact. Compat. Pol., 8, 69 (1993)