Compounds of the formula ##STR1## (wherein R.sub.1 is a lower alkyl group, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, represent a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a hydroxyl group, a trifluoromethyl group or a lower alkoxycarbonyl group; two adjacent groups of R.sub.2, R.sub.3 and R.sub.4 may combine to form a methylenedioxy group; n is an integer of 2 to 6) or salts thereof, are disclosed. These compounds are useful as agents for treating circulatory diseases because they have hypotensive action and are capable of increasing the cerebral blood flow, decreasing the heart rate and suppressing ventricular arrhythmia due to myocardial ischemia.
本发明公开了
化学式为##STR1##的化合物(其中R.sub.1是较低烷基基团,R.sub.2、R.sub.3和R.sub.4可以相同也可以不同,表示氢原子、卤素原子、较低烷基基团、较低烷氧基团、羟基、三
氟甲基基团或较低烷氧羰基基团;R.sub.2、R.sub.3和R.sub.4中的两个相邻基团可以结合形成亚甲二氧基基团;n为2至6的整数)或其盐。这些化合物可用作治疗循环系统疾病的药剂,因为它们具有降压作用,能够增加脑血流量,降低心率并抑制因心肌缺血而引起的室性心律失常。