反应详情

To a solution of sodium hydride (0.35 g) in N,N-dimethylformamide (30 ml) was added dropwise thioacetic S-acid (0.74 ml) with stirring under ice-cooling. The mixture was stirred at the same temperature for 30 minutes. A solution of (2S,4R)-4-methanesulfonyloxy-2-(3-methyl-2-oxoimidazolidin-1-yl)methyl-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (3.17 g) in N,N-dimethylformamide (7 ml) was added to the mixture obtained above with stirring at the same temperature. The mixture was stirred at 80°-90° C. for 2 hours. The reaction mixture was poured into ice-water (100 ml) and extracted twice with ethyl acetate (100 ml). The extract was washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate and evaporated in vacuo. The resulting residue was chromatographed on silica gel (100 g) eluting with a mixture of chloroform and methanol (19:1, V/V). The fractions containing the desired compound were collected and evaporated in vacuo to give (2S,4S)-4-acetylthio-2-(3-methyl-2-oxoimidazolidin-1-yl)methyl-1(4 -nitrobenzyloxycarbonyl)pyrrolidine (1.74 g).

1. temperaturecooling
2. stirringThe mixture was stirred at the same temperature for 30 minutes
3. customobtained above
4. stirringwith stirring at the same temperature
5. stirringThe mixture was stirred at 80°-90° C. for 2 hours
6. extractionextracted twice with ethyl acetate (100 ml)
7. washThe extract was washed with saturated aqueous sodium chloride
8. dry with materialdried over anhydrous magnesium sulfate
9. customevaporated in vacuo
10. customThe resulting residue was chromatographed on silica gel (100 g)
11. washeluting with a mixture of chloroform and methanol (19:1, V/V)
12. additionThe fractions containing the desired compound
13. customwere collected
14. customevaporated in vacuo