反应详情

To a stirred mixture of 4-(3,4-dihydro-2H-chromen-4-yloxy)-1,2-dimethyl-1H-benzimidazole-6-carboxylic acid (70 mg, 0.21 mmol, STEP 2) and 2-(methylamino)ethanol (31 mg, 0.41 mmol) in dimethylformamide (2 mL) were added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCl) (67 mg, 0.35 mmol) and 1-hydroxybenzotriazole hydrate (HOBt) (60 mg, 0.41 mmol) at room temperature. After stirring at room temperature for 18 hours, the reaction mixture was quenched with sodium hydrogencarbonate aqueous solution (5 mL), and extracted with ethyl acetate (50 mL×2). The combined extracts were washed with brine, dried over sodium sulfate, and concentrated in vacuum. The residue was purified by column chromatography on silica gel (ethyl acetate:methanol=10:1 as an eluent). The residue was suspended with diethyl ether, and collected by filtration to afford the title compound as a white solid (24 mg, 24%):

1. customthe reaction mixture was quenched with sodium hydrogencarbonate aqueous solution (5 mL)
2. extractionextracted with ethyl acetate (50 mL×2)
3. washThe combined extracts were washed with brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated in vacuum
6. customThe residue was purified by column chromatography on silica gel (ethyl acetate
7. filtrationcollected by filtration