申请人:Aktiebolaget Draco
公开号:EP0252043A1
公开(公告)日:1988-01-07
A method for the preparation of enprofylline is disclosed, which method comprises
a) treating 6-amino-l-n-propyl-2,4-(lH,3H)-pyrimidinedione in formic acid with sodium nitrite in the presence of a catalyst to the formation of 6-amino-5-formamido-l-n-propyl-2,4-(lH,3H)-pyrimidinedione and
b) performing a ring-closure reaction on the formed 6-amino-5-formamido-l-n-propyl-2,4-(lH,3H)-pyrimidinedione to the formation of 3,7-dihydro-3-n-propyl-lH-purin-2,6-dione.
本发明公开了一种制备恩丙茶碱的方法,该方法包括
a) 在催化剂存在下,用亚硝酸钠处理甲酸中的 6-氨基-l-正丙基-2,4-(lH,3H)-嘧啶二酮,形成 6-氨基-5-甲酰氨基-l-正丙基-2,4-(lH,3H)-嘧啶二酮,以及
b) 对形成的 6-氨基-5-甲酰氨基-l-正丙基-2,4-(lH,3H)-嘧啶二酮进行闭环反应,形成 3,7-二氢-3-正丙基-lH-嘌呤-2,6-二酮。