Triethylamine → (S)-4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylic acid (4-trifluoromethylphenyl)amide

(S)-2-Methyl-6-nitro-2-(piperazin-1-ylmethyl)-2,3-dihydroimidazo[2,1-b]oxazole dihydrochloride prepared in Example 408 (236 mg, 0.88 mmol) was dissolved in a mixture of methylene chloride (5 ml) and triethylamine (2 ml, 14.35 mmol). To the solution, a mixture of 4-aminobenzotrifluoride (142 mg, 0.882 mmol), 1,1′-carbonyldiimidazole (143 mg, 0.882 mmol) and DMF (6 ml) stirred at room temperature overnight was added followed by stirring at room temperature for 6 hours. To the reaction mixture, water was added, and the mixture was extracted with ethyl acetate. The organic phase was washed with water three times and a saturated saline solution, dried over sodium sulfate and then filtered. The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (methylene chloride/methanol=30/1) to afford (S)-4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylic acid (4-trifluoromethylphenyl)amide (90 mg, yield 23%) as a white powder.

1. additionwas added
2. stirringby stirring at room temperature for 6 hours
3. extractionthe mixture was extracted with ethyl acetate
4. washThe organic phase was washed with water three times
5. dry with materiala saturated saline solution, dried over sodium sulfate
6. filtrationfiltered
7. concentrationThe filtrate was concentrated under reduced pressure
8. customthe residue was purified by silica gel column chromatography (methylene chloride/methanol=30/1)

ORD record

ord-9046d6f4c13c441d9130b31a86c3d1a7

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07262212B2