Compounds of the formula (I), or pharmaceutically acceptable salts thereof ##STR1## wherein X is phenyl, optionally substituted by one halogen, C.sub.1-4 alkyl or C.sub.1-4 alkoxy; or pyridyl; R.sub.1 is hydrogen or C.sub.1-6 alkyl; and n is 1 to 6, pharmaceutical compositions containing them and a process for their preparation. These compounds are useful in the prophylaxis or treatment of diseases due to a histamine-mediated allergic response.
化合物的公式(I)或其药学上可接受的盐##STR1##其中X是苯基,可以选择性地被一个卤素,C.sub.1-4烷基或C.sub.1-4烷氧基取代;或者
吡啶基;R.sub.1是氢或C.sub.1-6烷基;n为1至6,包含它们的药物组合物以及它们的制备方法。这些化合物在预防或治疗由
组胺介导的过敏反应引起的疾病中很有用。