反应详情

To a stirring solution of 9-pivaloyloxymethyl-3,7-dimethyluric acid (0.14 g, 0.45 mmol) in dimethylsulfoxide (10 ml) was added sodium hydride (12 mg, 0.47 mmol) in one portion. The solution was stirred for 15 minutes. (R)-5-Acetoxy-1-iodohexane (0.13 g, 0.47 mmol) in dimethylsulfoxide (1 ml) was added. The solution of (R)-5-acetoxy-1-iodohexane was prepared according to methods described in U.S. patent application Ser. No. 09/002,345, which is incorporated herein by reference. After stirring at room temperature for 24 hours, water (25 ml) was added and the aqueous solution was extracted with ethyl acetate (3×15 ml). The combined extracts were washed with saturated aqueous sodium chloride solution (15 ml), dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by flash chromatography on silica eluting with ethyl acetate to give (R)-1-(5-acetoxyhexyl)-9-pivaloyloxymethyl-3,7-dimethyluric acid (0.10 g, 50% yield) as a white solid.

1. stirringAfter stirring at room temperature for 24 hours
2. extractionthe aqueous solution was extracted with ethyl acetate (3×15 ml)
3. washThe combined extracts were washed with saturated aqueous sodium chloride solution (15 ml)
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified by flash chromatography on silica eluting with ethyl acetate