反应详情

2.54 g of 4-chloro-3-sulfamoylbenzoyl chloride were added in little portions to the solution of 2.2 g of 1-amino-5-methoxycarbonylbenzimidazole-2-thione in 8 ml of dimethylformamide and 1.4 ml of triethylamine while stirring. The reaction mixture was set aside overnight, then the pH value was adjusted to 5 by acetic acid and it was diluted with 100 ml of water. The separated gum slowly disaggregated to a powder which was filtered by suction, washed with water and dried at 80° C. The crude product obtained was boiled with 10 ml of glacial acetic acid for 30 minutes, then poured into 50 ml of water. The separated gum disaggregated to a powder by stirring. The precipitate was filtered by suction, washed with water and dried at 80° C. to give 2.4 g (54.5%) of 1-(4'-chloro-3'-sulfamoylbenzoyl)amino-5-methoxycarbonylbenzimidazole-2-thione, as a beige powder, m.p.: 258°-261° C. (with decomposition) after recrystallization from a mixture of dimethylformamide and water (1:2).

1. filtrationwas filtered by suction
2. washwashed with water
3. customdried at 80° C
4. customThe crude product obtained
5. stirringby stirring
6. filtrationThe precipitate was filtered by suction
7. washwashed with water
8. customdried at 80° C.