反应详情

To a solution of benzhydryl 7β-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylate (2.47 g, 5.00 mmol) in methylene chloride (35 ml) was added under ice-cooling a solution of 2,3-dibromo-2-ethylbutanal (1.42 g, 5.50 mmol) in methylene chloride (5 ml) followed by addition of anhydrous magnesium sulfate. The resulting mixture was stirred at room temperature for 4 hours. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure and, after addition of benzene (20 ml) and thorough stirring, insolubles were filtered off. The filtrate was concentrated to dryness under reduced pressure and the reside was made powdery by the addition of ether (10 ml). The resulting powder was recovered by filtration and dried under reduced pressure to give 3.12 g (85%) of the title compound as a pale brown powder.

1. filtrationThe reaction mixture was filtered
2. concentrationthe filtrate was concentrated under reduced pressure
3. additionafter addition of benzene (20 ml) and thorough stirring, insolubles
4. filtrationwere filtered off
5. concentrationThe filtrate was concentrated to dryness under reduced pressure
6. additionthe reside was made powdery by the addition of ether (10 ml)
7. filtrationThe resulting powder was recovered by filtration
8. customdried under reduced pressure