申请人:ELI LILLY AND COMPANY
公开号:EP0091796A1
公开(公告)日:1983-10-19
This invention concerns a process for removing a sulfonyl group from the 1-position of a benzimidazole to allow conversion of 2-amino-1,5-substituted-benzimidazole compounds into 2-amino-1.6-substituted-benzimidazole compounds. The 5-isomer is reacted with an alkali metal hydroxide or carbonate in an inert aqueous organic solvent system. The reaction mixture is acidified to precipitate the base and form the intermediate benzimidazole tautomer. The intermediate is then reacted with a sulfonyl acylating agent or a haloalkyl isothiocyanate to form a mixture of 2-amino-1,5(6)-substituted-benzimidazole compounds. This invention also concerns the process for removing a sulfonyl group from the 1-position of a benzimidazole to allow conversion of 2-amino-1,6-substituted-benzimidazole compounds into 2-amino-1,5-substituted-benzimidazole compounds.
本发明涉及一种从苯并咪唑的 1 位去除磺酰基,从而将 2-氨基-1,5-取代苯并咪唑化合物转化为 2-氨基-1.6-取代苯并咪唑化合物的工艺。在惰性含水有机溶剂体系中,5-异构体与碱金属氢氧化物或碳酸盐发生反应。将反应混合物酸化,使碱沉淀,形成中间体苯并咪唑同系物。然后将中间体与磺酰基酰化剂或卤代烷基异硫氰酸酯反应,形成 2-氨基-1,5(6)-取代的苯并咪唑化合物混合物。本发明还涉及从苯并咪唑的 1 位上去除磺酰基,使 2-氨基-1,6-取代的苯并咪唑化合物转化为 2-氨基-1,5-取代的苯并咪唑化合物的工艺。