Abstract: Derivatives of aminopyridinecarboxylic acids which inhibit the dipeptidyl carboxy peptidase (DPCP), methods for their preparation and pharmaceutical compositions containing them.The compounds have formula: ##STR1## where Z is hydrogen, alkyl having from 1 to 3 carbon atoms, halogen or alkoxy having from 1 to 3 carbon atoms;R1 is hydrogen, alkyl having from 1 to 6 carbon atoms, arylalkyl having from 7 to 12 carbon atoms, aryl having from 6 to 15 carbon atoms;m and n are an integer of from 0 to 4 each provided, however, the m+n is lower than 5;R2 is hydrogen, alkyl having from 1 to 6 carbon atoms or arylalkyl having from 7 to 12 carbon atoms;R3 is hydrogen or acyl having from 1 to 8 carbon atoms;R4 is hydrogen or alkyl having from 1 to 3 carbon atoms;and their pharmaceutically acceptable salts with organic or inorganic acids.