反应详情

A mixture of methyl [5-(4-nitrobenzyl)imidazo[1,2-c]pyrimidin-8-yl]acetate (28 mg, 0.09 mmol) and Pd/C (wet, 3 mg) in methanol (1 mL) was stirred under hydrogen atmosphere for 1 hour. After the removal of Pd/C by filtration through a Celite pad, the filtrate was concentrated in vacuo. The resulting crude methyl [5-(4-aminobenzyl)imidazo[1,2-c]pyrimidin-8-yl]acetate (26 mg, 0.09 mmol) was dissolved with dichloromethane (1 mL). To this solution was added 3,4-dichloro-benzoic acid (20.1 mg, 0.11 mmol), 1-hydroxybenzotriazole (14.2 mg, 0.11 mmol), triethylamine (0.037 mL, 0.26 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (21.9 mg, 0.11 mmol) at room temperature. The mixture was stirred at room temperature overnight, and diluted with ethyl acetate. The solution was washed with water and brine, dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by preparative TLC (silica gel, chloroform:methanol, 19:1) to give methyl (5-{4-[(3,4-dichloro-benzoyl)amino]benzyl}imidazo[1,2-c]pyrimidin-8-yl)acetate (29 mg, 70%) as slightly yellow oil.

1. customAfter the removal of Pd/C
2. filtrationby filtration through a Celite pad
3. concentrationthe filtrate was concentrated in vacuo
4. stirringThe mixture was stirred at room temperature overnight
5. washThe solution was washed with water and brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe crude product was purified by preparative TLC (silica gel, chloroform:methanol, 19:1)