Various 9-substituted 8-phenyltheophyllines (III) were prepared in two steps starting from 5, 7-dimethyl-2-phenyloxazolo [5, 4-d] pyrimidine-4, 6 (5H, 7H)-dione (I). Thus, treatment of I with amines afforded 5-(N-substituted benzamidino)-1, 3-dimethylbarbituric acids (II). The reaction of II with thionyl chloride or phosphorus oxychloride gave III.
从 5,7-二甲基-2-苯基
噁唑并[5,4-d]
嘧啶-4,6 (5H,7H)-二酮(I)开始,分两步制备了各种 9-取代的
8-苯基茶碱(III)。因此,用胺处理 I 可以得到 5-(N-取代苯甲酰胺基)-1,3-二甲基
巴比妥酸(II)。II 与亚
硫酰氯或氧
氯化
磷反应后得到 III。