DERIVATIVES OF 1,2,4-TRIAZOLO[4,3-B]PYRIDO[3,2-D]-PYRIDAZINE, METHOD OF THEIR SYNTHESIS, PHARMACEUTICAL COMPOSITION AND METHOD OF INHIBITION OF PHOSPHODIESTERASE IV ACTIVITY Russian patent published in 2003 - IPC

FIELD: organic chemistry, biochemistry, pharmacy. SUBSTANCE: invention describes novel derivatives of 1,2,4-triazolo[4,3- b]pyrido[3,2-d]-pyridazine of the general formula (I) where R¹ means hydrogen atom or group -(CH₂)_m-Y where m means whole number from 0 to 4 and Y means C₁-C₆-alkyl, C₁-C₆-halogenalkyl, C₁-C₆--alkoxy-group, alkoxycarbonyl-group including up to 7 carbon atoms, C₃-C₇--cycloalkyl, norbornyl, phenylalkenyl group including up to 12 carbon atoms, phenyl group optionally substituted with one halogen atom or 4-pyridyl group; R² means phenyl group optionally substituted with one or more halogen atoms or C₁-C₆-alkyl, C₁-C₆-alkoxy-, C₃-C₆-cycloalkoxy- methylenedioxy-, nitro-, di- (C₁-C₆-alkyl)-amino-or trifluoromethyl-groups, naphthyl or thienyl group; R³ means hydrogen or halogen atom or C₁-C₆-alkyl group, and its pharmaceutically acceptable salts, method of their synthesis, pharmaceutical composition and method of inhibition of activity of phosphodiesterase IV. Describing compounds can be used for treatment of inflammatory and allergic diseases. EFFECT: improved method of synthesis, valuable biochemical and medicinal properties. 10 cl, 2 tbl