| abstract |
Addition compounds having the formula <IMAGE> (I) wherein R1 represents an aliphatic oxycarbonyl group, benzyloxycarbonyl group which can have nuclear substituents, or benzoyl, aromatic sulfonyl or aromatic sulfinyl group; R2 represents methyl, isopropyl, isobutyl, isoamyl or benzyl group; R3 represents a lower alkoxyl, benzyloxy or benzhydryloxy group and n represents 1 or 2 are produced by reacting an N-substituted monoaminodicarboxylic acid having the formula <IMAGE> (IV) with an amino carboxylic acid ester having the formula <IMAGE> (V) in the presence of a protease. |