摘要 |
The invention relates to compounds of the formula: <IMAGE> and pharmaceutically acceptable salts thereof, in which X represents either -CH= or -N=, R1 represents an alkyl radical having 1 to 5 carbon atoms, R2 represents hydrogen and R3 is an alkyl radical having 1 to 5 carbon atoms, or R2 and R3, together with the nitrogen atom to which they are bonded, represent a heterocyclic radical, such as pyrrolidinyl, morpholino, 4-phenyl-piperazinyl, in which the phenyl radical can carry one or more substituents, such as a halogen atom, an alkyl or alkoxy radical having 1 to 5 carbon atoms or the trifluoromethyl radical, or represents 4-(2-pyrimidinyl)-piperazinyl, having anti-bronchoconstrictory properties. |