反应详情

To a suspension of sodium borohydride (0.1 g) in tetrahydrofuran (10 ml) was added boron trifluoride etherate (0.3 ml) with stirring at 0°-10° C. After 30 minutes, a solution of (2S,4R)-1-benzyloxycarbonyl-4-methanesulfonyloxy-2- [(ureidocarbonylmethyl)oxymethyl]pyrrolidine (0.63 g) in tetrahydrofuran (5 ml) was added to the mixture at 0°-10° C. The mixture was stirred at the same condition for 2 hours and at ambient temperature for 15 hours. Methanol (5 ml) was added to the mixture at 0°-10° C. The mixture was stirred at ambient temperature for 3 hours and concentrated under reduced pressure to give a syrup. The syrup was subjected to a column chromatography on silica gel (25 g) and eluted with a mixture of methanol and chloroform (2:98 V/V) to give (2S,4R)-1-benzyloxycarbonyl-4-methanesulfonyloxy-2-[(2-ureidoethyl)oxymethyl]pyrrolidine (0.24 g).

1. stirringThe mixture was stirred at the same condition for 2 hours and at ambient temperature for 15 hours
2. stirringThe mixture was stirred at ambient temperature for 3 hours
3. concentrationconcentrated under reduced pressure
4. customto give a syrup
5. washeluted with a mixture of methanol and chloroform (2:98 V/V)