反应详情

To a mixture of tert-butyl (S)-[4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazin-1-yl]carbamate prepared in Example 503 (0.20 g, 0.523 mmol) and 5-chlorobenzofuran-2-carbaldehyde (0.113 g, 0.628 mmol) and methylene chloride (4 ml), trifluoroacetic acid (0.4 ml) was added followed by stirring at room temperature for 2 hours. To the reaction mixture, a saturated sodium hydrogencarbonate solution was added followed by extraction with methylene chloride. The organic phase was washed with a saturated saline solution, dried over sodium sulfate and then filtered. The resulting filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (methylene chloride/ethyl acetate=4/1) to afford (S)-N-(5-chlorobenzofuran-2-ylmethylene)-N-[4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazin-1-yl]amine (0.137 g, yield 59%) as a light yellow powder.

1. additionwas added
2. extractionfollowed by extraction with methylene chloride
3. washThe organic phase was washed with a saturated saline solution
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. concentrationThe resulting filtrate was concentrated under reduced pressure
7. customthe residue was purified by silica gel column chromatography (methylene chloride/ethyl acetate=4/1)