| 摘要 |
A 3(2H)pyridazinone of the formula: ( I ) wherein R1 is hydrogen, methyl, C3-C6 alkenyl, C5 or C6 cycloalkyl, benzyl, phenyl, -(CH2)mCO2R3 (wherein R3 is hydrogen or C1-C5 alkyl, and m is an integer of from 1 to 4), -(CH2)nA (wherein A is -OH or -N(R4)2 wherein R4 is C1-C3 alkyl, and n is an integer of from 2 to 6) or -CH2CF3; R2 is chlorine or bromine; each of Y1 and Y2 which may be the same or different, is hydrogen, C1-C5 alkyl, C2-C8 alkenyl, halogen, -OR5 (wherein R5 is hydrogen, C1-C8 alkyl or -(CH2)q wherein q is an integer of from 1 to 4), -CO2R6 (wherein R6 is hydrogen or C1-C5 alkyl), -N(R7)2 (wherein R7 is C1-C4 alkyl) or -SR8 (wherein R8 is C1-C4 alkyl); and Y3 is C1-C5 alkyl, C2-C4 alkyl); and Y3 is C1-C5 alkyl, C2-C8 alkenyl, halogen, -OR5 (wherein R5 is as defined above), -CO2R6 (wherein R6 is as defined above), -N(R7)2 (wherein R7 is as defined above) or -SR8 (wherein R8 is as defined above), or a pharmaceutically acceptable salt thereof. The compound exhibits antagonism against slow reacting substance of anaphylaxis (SRS-A) which induces a contraction of bronchial smooth muscle, and thus is useful as an anti-allergic agent. |
