Substituted picolinic acids, process for their preparation, their use and medicaments containing them

Substituted picolinic acids of the general formula I in which R denotes alkyl having 1 to 7 carbon atoms - but not butyl if R and R have the meaning alkyl and X denotes NH-, cycloalkylalkyl having 3 to 7 carbon atoms in the cycloalkyl moiety and 1 to 4 carbon atoms in the alkylene moiety, phenyl or substituted phenyl having up to three substituents from the group comprising halogen, hydroxyl, alkyl having 1 to 4 carbon atoms and alkoxy having 1 to 4 carbon atoms, R denotes alkyl having 1 to 4 carbon atoms or alkenyl having 3 to 5 carbon atoms, R denotes alkyl having 1 to 4 carbon atoms or alkenyl having 3 to 5 carbon atoms, or R and R together and including the nitrogen atom to which they are bonded denote pyrrolidino, morpholino, piperidino, hexahydroazepino or 1-piperazinyl substituted in the 4 position by R , R denotes hydrogen, alkyl having 1 to 4 carbon atoms, phenyl, benzyl or substituted phenyl having up to 3 substituents from the group comprising halogen, hydroxyl, alkyl having 1 to 4 carbon atoms and alkoxy having 1 to 4 carbon atoms, A denotes straight-chain or branched alkylene having 1 to 5 carbon atoms and X denotes O (oxygen) or NH, and the acid addition salts of these compounds, where R , R and R do not simultaneously denote alkyl if X represents O (oxygen) and A represents ethylene, are novel compounds having hypotensive activity. Processes for the preparation of these compounds are given.