PYRIDAZINONE DERIVATIVES WITH PHARMACEUTICAL ACTIVITY

摘要

A 3(2H)-pyridazinone derivative of formula (I), its salt, a process for its production and a pharmaceutical composition containing it, wherein each of R<1>, R<2> and R<3> which are independent of one another, is a hydrogen atom or a C1-4 alkyl group, X is a chlorine atom or a bromine atom, Y<1> is a hydrogen atom, a halogen atom, a nitro group, an amino group or a C1-4 alkoxy group, Y<2> is a hydrogen atom, a halogen atom, a hydroxyl group, a C1-4 alkyl group or a C1-4 alkoxy group, A is a C1-5 alkylene chain which may be substituted by a hydroxyl group, B is a carbonyl group or a methylene chain which may be substitued by a C1-4 alkyl group, and each of R<4> and R<5> which are independent of each other, is a C1-4 alkyl group, or R<4> is a hydrogen atom and R<5> is -Z-Ar (wherein Z is a C1-5 alkylene chain, and Ar is an aromatic 6-membered ring which may contain a nitrogen atom), or R<4> and R<5> together form a C2-6 cyclic alkylene group, or R<4> and R<5> form together with the adjacent nitrogen atom a 4-substituted piperazine ring of formula (a), wherein R<6> is a C1-4 alkyl group.