Benzene compounds having two pyridazinone substituents

摘要

The invention relates to pyridazinone derivatives which have inotropic, vasodilator and bronchodilator activity. The compounds of the invention are described by formula (I): <IMAGE> (I) wherein: R1 is hydrogen or methyl; R2 is hydrogen or methyl; and represent double or single bonds; and the benzene ring is para- or meta-substituted; and pharmaceutically acceptable salts thereof.