反应详情

For Examples 42 and 43, pyridine hydrochloride (668 mg, 5.78 mmol) and triethyl orthopropionate (3.4 mL, 17 mmol) were added to a solution of ethyl 4-[(8-amino-5,6-dimethyltetraazolo[1,5-a]pyridin-7-yl)amino]butanoate (4.5 g, 15 mmol) in toluene (100 mL). The reaction and work-up procedure were as described for Examples 40 and 41. The crude product was recrystallized from ethyl acetate:hexane, isolated by filtration, washed with ethyl acetate:hexane, and dried under high vacuum to provide 4.7 g of ethyl 4-(8-ethyl-5,6-dimethyl-7H-imidazo[4,5-c]tetraazolo[1,5-a]pyridin-7-yl)butanoate as off-white crystals.

1. customThe reaction
2. customThe crude product was recrystallized from ethyl acetate
3. customhexane, isolated by filtration
4. washwashed with ethyl acetate
5. dry with materialhexane, and dried under high vacuum