Process for brominating ergot alkaloids
    1.
    发明授权
    Process for brominating ergot alkaloids 失效
    溴化麦角生物碱的工艺

    公开(公告)号:US4609731A

    公开(公告)日:1986-09-02

    申请号:US141304

    申请日:1980-04-18

    摘要: The present invention provides an improved process for the production of a compound of formula I ##STR1## wherein R.sub.1 is carboxyl, alkoxy(C.sub.1-5)carbonyl, amido, alkyl(C.sub.1-5)amido, di(alkyl(C.sub.1-5)amido or an amido radical of formula II ##STR2## wherein R.sub.a is alkyl(C.sub.1-4),R.sub.b is alkyl(C.sub.1-4) or benzyl, andR.sub.2 is hydrogen or alkyl(C.sub.1-4), andeitherR.sub.3 is hydrogen and R.sub.4 is hydrogen or alkoxy(C.sub.1-4)orR.sub.3 and R.sub.4 together are a single bond,characterized in that a compound of formula III ##STR3## wherein R.sub.1 to R.sub.4 are as defined above,is brominated with a bromine complex of 3-bromo-6-chloro-2-methyl-imidazo[1,2-b]pyridazine.

    摘要翻译: 本发明提供了制备式I化合物I的改进方法,其中R 1是羧基,烷氧基(C 1-5)羰基,酰氨基,烷基(C 1-5)酰氨基,二(烷基(C 1-5) )酰氨基或式II的酰胺基其中R a是烷基(C 1-4),R b是烷基(C 1-4)或苄基,并且R 2是氢或烷基(C 1-4),并且R 3是 氢和R4是氢或烷氧基(C1-4)或R3和R4一起是单键,其特征在于其中R 1至R 4如上定义的式III化合物III与溴络合物溴化 3-溴-6-氯-2-甲基 - 咪唑并[1,2-b]哒嗪。