Trifluoroacetic acid → HCID 69481781, compound

Participants

Reaction Steps

A mixture of tert-butyl 4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylate prepared in Example 306 (140 mg, 0.38 mmol) and trifluoroacetic acid (3 ml) was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure, and the residue was dissolved in methylene chloride (3 ml), then neutralized with triethylamine (2 ml, 14.35 mmol). To the solution, isopropylisocyanate (75 μl, 0.76 mmol) was added followed by stirring at room temperature for 1 hour, then diluted with water. The solution was extracted with methylene chloride. The organic phase was dried over magnesium sulfate and then filtered. The filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methylene chloride/methanol=50/1) to afford 4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylic acid isopropylamide (90 mg, yield 67%) as a white powder.

Provenance & Evidence