The known blood platelet antiaggregative agent 6,7-dichloro-1,5-dihydroimidazo[2,1-b]quinazolin-2(3H)-one is prepared in high yield via an improved process involving a novel intermediate of the Formula ##STR1## in which R.sup.1 is (lower)alkyl and X is bromo, chloro or iodo. Two processes for the preparation of compounds of the Formula III are disclosed, one of which involves the novel intermediate ##STR2##
已知的血小板抗聚集剂6,7-二
氯-1,5-二氢
咪唑并[2,1-b]
喹唑啉-2(3H)-酮,通过一种涉及新型中间体的改进工艺高产率制备,该中间体的
化学式为##STR1##其中R.sup.1为(较低)烷基,X为
溴、
氯或
碘。公开了两种制备化合物III的方法,其中一种涉及新型中间体##STR2##