申请人:EGIS Gyogyszergyar
公开号:US05391737A1
公开(公告)日:1995-02-21
This invention relates to a new and improved process for the preparation of 6,7-dichloro-1,5-dihydroimidazo[2,1-b]-quinazolin-2[3H]-one of formula ##STR1## (anagrelide), a valuable blood platelet antiaggregative compound. According to the process of the invention the compound of formula (I) is prepared by subjecting a new 2-cyanoiminoquinazoline derivative of the general formula ##STR2## wherein R stands for cyano or a group of the formula COOR.sup.1, in the latter R.sup.1 representing lower alkyl optionally carrying a phenyl substituent, to thermal cyclization in an acidic medium. The invention also relates to new 2-cyanoiminoquinazo-lines of the general formula (III) used for the production of anagrelide and to the preparation of the said compounds. The invention provides an advantageous process for the preparation of anagrelide which is devoid of the drawbacks of the hitherto known processes and renders possible the production of the compound of the formula (I) on industrial scale, too.
本发明涉及一种新的、改进的制备6,7-二氯-1,5-二氢咪唑[2,1-b]-喹唑啉-2 [3H] -酮的过程,其化学式为##STR1##(安格雷利德),这是一种有价值的血小板抗凝血化合物。根据本发明的过程,化合物(I)的制备是通过将一种新的2-氰基亚咯并喹唑啉衍生物(III)置于酸性介质中进行热环化反应,其中R代表氰基或公式COOR.sup.1的基团,在后者中R.sup.1代表可选携带苯基取代的低烷基。本发明还涉及用于生产安格雷利德的新的2-氰基亚咯并喹唑啉(III)的制备方法。本发明提供了一种优越的制备安格雷利德的方法,该方法摆脱了迄今已知方法的缺点,并使化合物(I)的工业规模生产成为可能。