反应详情

To a solution of 7β-amino-3-(trityl-1,2,3-triazol-4-ylthiomethylthio)-3-cephem-4-carboxylic acid diphenylmethyl ester (800 mg: 1.06 mMol.) and D-(-)-mandelic acid (242 mg: 1.59 mMol.) in dichloromethane (4 ml) is added dicyclohexylcarbodiimide (328 mg: 1.59 mMol.), and the mixture is stirred under ice cooling for 1 hour. The reaction mixture is concentrated, diluted with ethyl acetate, and filtered to remove solid. The filtrate is washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. The residue is purified by Lobar column chromatography (toluene: ethyl acetate=2:1) to give 7β-D-mandelamido-3-(trityl-1,2,3-triazol-4-ylthiomethylthio)-3-cephem-4-carboxylic acid diphenylmethyl ester (466 mg) as yellow foam. Yield: 50%.

1. concentrationThe reaction mixture is concentrated
2. additiondiluted with ethyl acetate
3. filtrationfiltered
4. customto remove solid
5. washThe filtrate is washed with brine
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe residue is purified by Lobar column chromatography (toluene: ethyl acetate=2:1)