反应详情

A solution of (2S,4R)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl)-2-[(2-ureidoethyl)oxymethyl]pyrrolidine (1.37 g) in dimethylformamide (3 ml) was added to a reaction mixture of thioacetic S-acid (0.32 ml) and sodium hydride (62.8% in oil suspension) (0.14 g) in dimethylformamide (7 ml) in a nitrogen stream, and the mixture was heated at 70°-75° C. for 5 hours. The reaction mixture was poured into ice-water (100 ml), extracted with ethyl, acetate (50 ml×2), dried over magnesium sulfate and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (20 g) and eluted with a mixture of methanol and chloroform (2:98 V/V) to give (2S,4S)-4-acetylthio-1-(4-nitrobenzyloxycarbonyl)-2-[(2-ureidoethyl)oxymethyl]pyrrolidine (1.02 g).

1. temperaturethe mixture was heated at 70°-75° C. for 5 hours
2. extractionextracted with ethyl, acetate (50 ml×2)
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customto give a syrup
6. washeluted with a mixture of methanol and chloroform (2:98 V/V)