C([O:3][C:4]([C:6]1[N:10]2[CH:11]=[C:12]([CH3:16])[CH:13]=[C:14]([Br:15])[C:9]2=[N:8][C:7]=1[S:17][CH3:18])=[O:5])C.[OH-].[Na+].Cl>C(O)C>[Br:15][C:14]1[C:9]2[N:10]([C:6]([C:4]([OH:5])=[O:3])=[C:7]([S:17][CH3:18])[N:8]=2)[CH:11]=[C:12]([CH3:16])[CH:13]=18-Bromo-6-methyl-2-(methylsulfanyl)imidazo[1,2-a]pyridin-3-carboxylic acid ethyl ester (1.33 g) was dissolved in ethanol (50 mL), then a 5N aqueous sodium hydroxide solution (3 mL) was added thereto, and the mixture was stirred under reflux for 1 hour. Ice was added to the reaction mixture, then 2N hydrochloric acid (8 mL) was further added thereto, and as a result, the precipitates were obtained. The resulting precipitates were collected by filtration, washed with water, and dried under reduced pressure to give 8-bromo-6-methyl-2-(methylsulfanyl)imidazo[1,2-a]pyridine-3-carboxylic acid (1.1 g) as a white powder.
불러오는 중…
