The present invention includes compounds represented by the formula: ##STR1## wherein X is O or S; R.sub.1 and R.sub.2 are independently selected from the group consisting of hydrogen, hydroxy, halo, loweralkoxy, thioalkoxy and loweralkyl; or R.sub.1 and R.sub.2 taken together can form a methylenedioxy or ethylenedioxy bridge; R.sub.3 is loweralkyl; R.sub.4 is selected from ##STR2## wherein Y is O or S, R.sub.6 is hydrogen, methoxy or halo and m is 0 or 1; R.sub.5 is hydrogen, loweralkyl, phenyl or substituted phenyl wherein the phenyl ring is substituted with one, two or three substituents independently selected from loweralkyl, halo, hydroxy, loweralkoxy, amino and thioalkoxy; and R.sub.8 is hydrogen or R.sub.3 and R.sub.8 taken together form a pyrrolidine ring; or a pharmaceutically acceptable salt thereof.
本发明包括由以下式表示的化合物:##STR1## 其中X为O或S;R.sub.1和R.sub.2分别选自氢、羟基、卤、低烷氧基、
硫代烷氧基和低烷基的群;或R.sub.1和R.sub.2一起可以形成一个亚甲二氧桥或
乙烯二氧桥;R.sub.3为低烷基;R.sub.4选自##STR2## 其中Y为O或S,R.sub.6为氢、甲氧基或卤,m为0或1;R.sub.5为氢、低烷基、苯基或取代苯基,其中苯环上取代基可独立选自低烷基、卤、羟基、低烷氧基、
氨基和
硫代烷氧基;R.sub.8为氢或R.sub.3和R.sub.8一起形成
吡咯烷环;或其药学上可接受的盐。