反应详情

To a solution of 2-ethoxy-1-{[2′-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl}-1H-benzimidazole-7-carboxylic acid (4.0 g) and triethylamine (1.3 mL) in THF (50 mL) was added dropwise 2,4,6-trichlorobenzoyl chloride (1.4 mL) under ice-cooling. After stirring at room temperature for 12 hrs., insoluble material was filtered off and the filtrate was concentrated. The residue was dissolved in methylene chloride (50 mL) and 5-oxotetrahydro-2-furanyl (0.67 g) and N,N-dimethylaminopyridine (1.0 g) were added under ice-cooling. After stirring at room temperature for 4 hrs., the reaction mixture was diluted with chloroform (150 mL), washed with water, saturated aqueous sodium hydrogen carbonate, 1 N hydrochloric acid and saturated brine, dried over anhydrous sodium sulfate and concentrated. The residue was purified by silica gel column chromatography to give the title compound (0.16 g, 3.3%) as a colorless solid.

1. temperaturecooling
2. filtration, insoluble material was filtered off
3. concentrationthe filtrate was concentrated
4. dissolutionThe residue was dissolved in methylene chloride (50 mL)
5. addition5-oxotetrahydro-2-furanyl (0.67 g) and N,N-dimethylaminopyridine (1.0 g) were added under ice-
6. temperaturecooling
7. stirringAfter stirring at room temperature for 4 hrs
8. addition, the reaction mixture was diluted with chloroform (150 mL)
9. washwashed with water, saturated aqueous sodium hydrogen carbonate, 1 N hydrochloric acid and saturated brine
10. dry with materialdried over anhydrous sodium sulfate
11. concentrationconcentrated
12. customThe residue was purified by silica gel column chromatography