New pyridazine derivatives, process of preparation and pharmaceutical compositions containing them

摘要

The subject of the invention is new pyridazine derivatives. These derivatives correspond to the general formula: <IMAGE> in which R1 and R2 each independently denote hydrogen, a halogen atom or a trifluoromethyl group, R3 represents a C1-C4 alkyl group, R4 represents: - a group <IMAGE> in which Alk denotes a C1-C3 alkylene group and R5 denotes a C1-C4 alkyl group; - a group <IMAGE> in which the Alk group is as defined above and substitutes the pyridine in the 2- or 3-position and their pharmaceutically acceptable salts. Application: medicaments active on the cholinergic system.