反应详情

Trifluoroacetic acid (2 ml) was added to a solution of 2-(2-methoxymethoxyethyl)-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole prepared in Example 25 (0.2 g, 0.822 mmol) in methylene chloride (10 ml) followed by stirring at room temperature overnight. The mixture was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (methylene chloride/methanol=100/1), and crystallized from methanol-diisopropyl ether to afford 2-(2-hydroxyethyl)-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole (0.11 g, yield 65%) as a light yellow powder.

1. concentrationThe mixture was concentrated under reduced pressure
2. customthe residue was purified by silica gel column chromatography (methylene chloride/methanol=100/1)
3. customcrystallized from methanol-diisopropyl ether