Oxidative cyclization of<i>n</i>-methyl- and<i>n</i>-benzoylpyridylthioureas. Preparation of new thiazolo[4,5-<i>b</i>] and [5,4-<i>b</i>] pyridine derivatives
作者:Karine Jouve、Jan Bergman
DOI:10.1002/jhet.5570400210
日期:2003.3
Cyclization of N-methyl- and N-benzoylpyridylthioureas, prepared from the corresponding aminopy-ridines, has been realized using various conditions. With bromine in acetic acid or potassium ferricyanide, the cyclization occurred on the nitrogen of the pyridine ring and pyridinium salts or 1,2,4-fhiadiazolo[2,3-a]pyridylidene systems were obtained. On the other hand, treatment of the thioureas with
由相应的氨基吡啶-吡啶制备的N-甲基和N-苯甲酰基吡啶基硫脲的环化已经使用各种条件实现。用溴在乙酸或铁氰化钾中的环化反应在吡啶环的氮上进行,得到吡啶鎓盐或1,2,4-噻二唑并[2,3- a ]吡啶亚砜体系。另一方面,在N-甲基吡咯烷酮(NMP)中用甲醇钠处理硫脲导致导致噻唑并[4,5- b ]和[5,4- b ]吡啶的形成,这是生物学评估中令人关注的目标。