Novel pyrazolopyridylpyridazinone derivatives characterized by being represented by general formula (1) and pharnacologically acceptable salts thereof, which exhibit a phosphodiesterase inhibiting activity and have a selective potent bronchodilating effect on the respiratory tract; a process for the preparation of them; and bronchodilators containing the same as the active ingredient; wherein R1 is C1-C4 lower alkyl or C3-C6 cycloalkyl; and R2, R3, R4 and R5 are each independently hydrogen, C1-C4 lower alkyl or phenyl, or alternatively R3 and R5 may be united to form a double bond.
新型
吡唑并
吡啶并
吡嗪酮衍
生物,其特征在于由通式(1)表示及其药理学上可接受的盐,该衍
生物表现出
磷酸二酯酶抑制活性,并对呼吸道具有选择性强效的支气管扩张作用;其制备方法;以及含有该衍
生物作为活性成分的支气管扩张剂;其中R1为C1-C4低级烷基或C3-C6环烷基;R2、R3、R4和R5各自独立地为氢、C1-C4低级烷基或苯基,或者R3和R5可以连接形成双键。