The compound of the formula: ##STR1## wherein R.sup.1 is straight chain alkyl, branched chain alkyl, cycloalkyl, hydroxyalkyl, fluoroalkyl, or polyfluoroalkyl; and one of R.sup.2, R.sup.3 and R.sup.4 is hydroxyl and the other two are, independently, H, CN, halogen, alkyl or hydroxyl; or a pharmaceutically acceptable salt thereof, is useful as a smooth muscle relaxant.
该化合物的
化学式为:##STR1## 其中R.sup.1是直链烷基,支链烷基,环烷基,羟基烷基,氟烷基或多氟烷基;R.sup.2,R.sup.3和R.sup.4中的一个是羟基,另外两个是独立的H,CN,卤素,烷基或羟基;或其药学上可接受的盐,可用作平滑肌松弛剂。