Method for preparation of 3,7-bis-(dimethylamino)-phenothiazin-5-ium chloride or bromide
申请人:MIKROCHEM spol, s r.o.
公开号:US11059797B2
公开(公告)日:2021-07-13
The present invention relates to: a process for preparing 3,7-bis-(dimethylamino)-phenothiazin-5-ium bromide or chloride; a method of converting 3,7-bis-(dimethylamino)-phenothiazin-5-ium bromide to 3,7-bis-(di-methylamino)-phenothiazin-5-ium chloride; and the purification of 7-bis-(di-methylamino)-phenothiazin-5-ium chloride by crystallization from aqueous solution of hydrochloric acid, leading to a pharmaceutically acceptable 3,7-bis-(di-methylamino)-phenothiazin-5-ium chloride (methylthioninium chloride, methylene blue, MTC) of formula I below reported.
本发明涉及一种制备 3,7-双-(二甲基氨基)-吩噻嗪-5-鎓溴化物或氯化物的工艺;一种将 3,7-双-(二甲基氨基)-吩噻嗪-5-鎓溴化物转化为 3,7-双-(二甲基氨基)-吩噻嗪-5-鎓氯化物的方法;以及通过从盐酸水溶液中结晶纯化 7-双(二甲基氨基)-吩噻嗪-5-鎓氯化物,得到药学上可接受的下述式 I 的 3,7-双(二甲基氨基)-吩噻嗪-5-鎓氯化物(甲硫鎓氯化物,亚甲基蓝,MTC)。