Esters and amides of several α-aza-amino-acids (carbazic acids), and intermediates of use in the introduction into peptides of α-aza-glycyl,-alanyl,-valyl,-leucyl,-isoleucyl,-phenylalanyl,- tyrosyl,-tryptophyl,-prolyl,-aspartyl,-asparaginyl,-glutamyl,-glutaminyl, and-pyroglutaminyl residues are described. t-Butyl 3-alkyl-or-aralkyl carbazates, obtained by catalytic hydrogenation of the corresponding hydrazones, were the most versatile intermediates; ...
