The peptides of alpha-aminosuberic acid I. New intermediates for synthetic studies

The paper describes the synthesis of alpha-aminosuberic acid derivatives suitable for the synthesis of peptides. These include Z-, Boc- and Fmoc-protection on the alpha-amino group, benzyl ester, Boc-hydrazide and Z-hydrazide as well as the free carboxylic function in the side chain, and methyl ester, benzyl ester or free alpha-carboxylic group. Their use is demonstrated on the synthesis of the respective derivatives of Asu-Val-Leu. The enzyme catalyzed reaction was successfully used both as a route to L-Asu from the D,L-compound as well as for the direct synthesis of the optically active tripeptide derivative from the Z-D,L-Asu-OH.