Compounds of formula (I) ##STR1## in which R.sub.1 is hydrogen, R.sub.2 is hydrogen or C.sub.1-6 alkyl, R.sub.3 and R.sub.4 independently represent one or more radicals selected from hydrogen, NH.sub.2, NO.sub.2, halogen, hydroxy, C.sub.1-6 alkoxy or C.sub.1-6 alkyl, X represents S or --CH.dbd.CH-- group and pharmaceutically acceptable salts are NMDA receptor antagonists.
化合物的公式(I) ##STR1## 中,其中R.sub.1是氢,R.sub.2是氢或C.sub.1-6烷基,R.sub.3和R.sub.4分别代表从氢,NH.sub.2,NO.sub.2,卤素,羟基,C.sub.1-6烷氧基或C.sub.1-6烷基中选择的一个或多个基团,X代表S或--CH.dbd.CH--基团,且药用盐是N
MDA受体拮抗剂。