反应详情

1.85 ml of methanesulfonyl chloride was added, whilst ice-cooling, to a solution of 5.0 g of (2S, 4R)-1-(t-butoxycarbonyl)-2-carbamoyl-4-hydroxypyrrolidine [prepared as described in step (2) above] in 250 ml of dry tetrahydrofuran, followed by 3.31 ml of triethylamine. The mixture was then stirred at 0° to 5° C. for 1 hour, after which it was poured into an aqueous solution of sodium chloride and extracted with ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, and the solvent was removed by distillation under reduced pressure. The residue was purified by chromatography through silica gel (eluted with a 9:1 by volume mixture of ethyl acetate and methanol) to afford 5.5 g of the title compound as colorless crystals.

1. extractionextracted with ethyl acetate
2. washThe extract was washed with an aqueous solution of sodium chloride
3. dry with materialdried over anhydrous magnesium sulfate
4. customthe solvent was removed by distillation under reduced pressure
5. customThe residue was purified by chromatography through silica gel (
6. washeluted with a 9:1 by volume mixture of ethyl acetate and methanol)