One-Pot Synthesis of Dipeptides and Unsymmetrical Peptidyl Ureas from Unprotected NCA, Synthesis of Dipeptides and Unsymmetrical Peptidyl Ureas
Julia Mateos-Caro, Yves Robin, Vincent Levacher,* Francis Marsais , Synlett 2009 pp 279-283
N-protected carboxyanhydrides (NCA) - peptidyl ureas - dipeptides
We report herein new labile protecting groups of N-carboxyanhydrides (NCA) useful to prevent polymerization during coupling reactions with nitrogen nucleophiles. Thus, N-sulfinyl-NCA 1 and N-silyl-NCA 2 were prepared in situ and involved, without being isolated, in coupling reactions with various α-amino esters to furnish dipeptides 3 and unsymmetrical peptidyl ureas 4, respectively, in good yields.