Compounds of the general formula ##STR1## wherein R.sub.1 is n-propyl or cyclobutyl; R.sub.2 is isopropyl, tertiary butyl, cyclobutyl, cyclopentyl or cyclohexyl; R.sub.3 is hydrogen; R.sub.4 is hydrogen or methyl; as (R)-enantiomer in the form of free base or pharmaceutically acceptable salts thereof, process for their preparation, pharmaceutical composition, use of and method of treatment of disorders in CNS.
通式为##STR1##的化合物,其中R.sub.1为正丙基或
环丁基;R.sub.2为异丙基、叔丁基、
环丁基、环戊基或环己基;R.sub.3为氢;R.sub.4为氢或甲基;作为(R)-对映体的自由碱形式或其药用可接受的盐,其制备方法,药物组合物,在中枢神经系统疾病治疗中的使用和方法。