反应详情

温度

-78 °C

To a solution of 2-acetylthiomethylthiopyridine (249 mg: 1.25 mMol.) in a mixture of dimethylformamide (4 ml) and tetrahydrofuran (2 ml) cooling at -78° C. is added dropwise 1.26N-sodium methoxide-methanol solution (0.87 ml: 1.10 mMol.), and the mixture is stirred at -78° C. for 15 minutes. To this reaction mixture is added a solution of 7β-[(Z)-2-(2-t-butoxycarbonylaminothiazol-4-yl)-2-trityloxyiminoacetamido]-3-methanesulfonyloxy-3-cephem-4-carboxylic acid diphenylmethyl ester (971 mg: 1.00 mMol.) in dimethylformamide (2 ml) and the mixture is stirred at -78° C. for 1 hour. The reaction mixture is mixed with 10% hydrochloric acid to stop the reaction, diluted with water, and extracted with ethyl acetate. The extract is washed with dilute aqueous sodium hydrogen carbonate and brine, dried over sodium sulfate, and concentrated. The residue is purified by silica gel chromatography (toluene: ethyl acetate=4:1) and silica gel rechromatography (toluene: ethyl acetate=7:1) to give 7β-[(Z)-2-(2-t-butoxycarbonylaminothiazol-4-yl)-2-trityloxyiminoacetamido]-3-(pyrid-2-ylthiomethylthio)-3-cephem-4-carboxylic acid diphenylmethyl ester as colorless foam (753 mg). Yield: 73%.

1. stirringthe mixture is stirred at -78° C. for 1 hour
2. customthe reaction
3. extractionextracted with ethyl acetate
4. washThe extract is washed with dilute aqueous sodium hydrogen carbonate and brine
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated
7. customThe residue is purified by silica gel chromatography (toluene: ethyl acetate=4:1) and silica gel rechromatography (toluene: ethyl acetate=7:1)