Compounds having the structure ##STR1## and pharmaceutically acceptable salts thereof, wherein Z is oxygen, sulfur or methylene; R.sub.1 is hydrogen, halogen, alkyl, aryl or arylalkyl; R.sub.2 is hydrogen, alkyl, aryl, or arylalkyl; R.sub.3 is hydrogen, alkyl, aryl or arylalkyl; and R.sub.4 is hydrogen, halogen, alkyl, phenyl, dialkylamidosulfonyl or trifluoromethyl, have useful central nervous system activity.
具有结构##STR1##和其药学上可接受的盐,其中Z为氧、
硫或亚甲基;R.sub.1为氢、卤素、烷基、芳基或芳基烷基;R.sub.2为氢、烷基、芳基或芳基烷基;R.sub.3为氢、烷基、芳基或芳基烷基;R.sub.4为氢、卤素、烷基、苯基、二烷基
氨基磺酰基或三
氟甲基,具有有用的中枢神经系统活性。