反应详情

4-Trifluoromethoxybenzyl (S)-4-[3-(2-chloro-4-nitroimidazol-1-yl)-2-hydroxy-2-methylpropyl]-piperazine-1-carboxylate prepared in Example 390 (4.3 g, 8.24 mmol) was dissolved in DMF (13 ml). To the solution, sodium hydride (430 mg, 10.7 mmol) was added followed by stirring at the same temperature for 2 hours with cooling on ice-bath. To the reaction mixture, ethyl acetate (4.3 ml) and water (30 ml) were added in this order, and the solution was stirred for 30 minutes. The precipitates were filtered off and washed with water. The solids obtained were recrystallized from ethyl acetate/isopropyl ether and then recrystallized from isopropyl alcohol to afford 4-trifluoromethoxybenzyl (S)-4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylate (3.15 g, yield 79%) as a white powder.

1. temperaturewith cooling on ice-bath
2. stirringthe solution was stirred for 30 minutes
3. filtrationThe precipitates were filtered off
4. washwashed with water
5. customThe solids obtained
6. customwere recrystallized from ethyl acetate/isopropyl ether
7. customrecrystallized from isopropyl alcohol