反应详情

In 50 ml of water is suspended 4.60 g of 7β-amino-3-hydroxymethyl-3-cephem-4-carboxylic acid and, with ice-cooling and stirring, 20 ml of 1N aqueous sodium hydroxide solution is added to the suspension for dissolving the acid. To the solution is added 1.85 g of sodium hydrogen carbonate and, then, a solution of 4.11 g of 2-methylsulfonylethoxycarbonyl chloride in 40 ml of tetrahydrofuran is added dropwise. The mixtrue is stirred with ice-cooling for 2 hours, then adjusted to pH 6.5, washed with ethyl acetate, and concentrated under reduced pressure. The residue is subjected to column chromatography on XAD-II (600 ml). Elution is performed with water and the eluate is concentrated under reduced pressure and freeze-dried to give 3.10 g of sodium 7β-(2-methylsulfonylethoxycarbonylamino)-3-hydroxymethyl-3-cephem-4-carboxylate as light yellow powders.

1. temperaturewith ice-cooling
2. dissolutionfor dissolving the acid
3. stirringThe mixtrue is stirred with ice-
4. temperaturecooling for 2 hours
5. washwashed with ethyl acetate
6. concentrationconcentrated under reduced pressure
7. washElution
8. concentrationthe eluate is concentrated under reduced pressure
9. customfreeze-dried