Verfahren zur Herstellung von Arginin enthaltenden Peptiden

In a process for preparing arginine-containing polypeptides the guanidino group is protected by the p-nitrocarbobenzoxy radical and the resulting peptide condensed with another peptide residue. The protecting group may be removed at any stage by catalytic hydrogenation. The protecting group is stable to many known methods for preparing polypeptides, e.g. the azide method, the mixed anhydride method, the method of activated esters, the dicyclohexyl carbodiimide and diimidazole carbonyl methods. N - (Guanidino) - p - nitrocarbobenzoxy - Larginine dihydrobromide is prepared by reacting p-nitrobenzyloxycarbonyl chloride with Na -carbobenzoxy-L-arginine to form Na -carbobenzoxy - N - (guanidino) - p - nitrocarbobenzoxy - L - arginine and reacting this with HBr.