DERIVATIVES OF 3(2H)-PYRIDAZINONES OR THEIR PHARMACEUTICALLY ACCEPTABLE ADDITIVE ACID SALTS AND PHARMACEUTICAL COMPOSITION ON SAID Russian patent published in 1999 - IPC

FIELD: organic chemistry, pharmacy. SUBSTANCE: invention proposes a new 3(2H)-pyridazinone derivative of the formula (I) where R¹ means hydrogen atom or C_1-4-alkyl; each of R² and R³ means hydrogen atom; X means chlorine or bromine atom; Y¹ means hydrogen, halogen atom, nitro-group or C_1-4-alkoxy-group; Y² means C_1-4-alkoxy-group; A means C_1-5- -alkylene chain that can be substituted with hydroxyl-group; B means carbonyl group or methylene chain that can be substituted with C_1-4-alkyl group; (a) R⁴ means hydrogen atom; R⁵ means Z-Ar where Z means C_1-5-alkylene chain and Ar means pyridyl or (b) R⁴ and R⁵ taken in common with adjacent nitrogen atom form 4-substituted piperazine ring of the formula (II) where R⁶ means C_1-4-alkyl group that can be substituted with phenyl group that can be substituted with Y³ where Y³ means halogen atom, amino-group, N-formylamino-group or C_1-4-alkylcarbonylamino-group; pyridyl, quinoline or the group of the formula (III) where R⁹ is C_1-4-alkyl or benzyl that can be substituted with halogen atom, or (c) R⁴ and R⁵ in common with adjacent nitrogen atom form 4-substituted piperidine ring of the formula (IV) where R¹¹ is C_1-4-alkyl that can be substituted with phenyl group. Compounds show bronchodilating, antiallergic and/or antithrombosis activity. Invention describes also acceptable additive acid salts and a pharmaceutical composition based on the compound of the formula (I). EFFECT: new compounds indicated above, valuable pharmacological activities. 3 cl, 5 tbl, 14 ex