反应详情

To an ice-cooled solution of the crude product obtained in Step 5 (5.6 g) and (6R,7R)-7-amino-3-[(2-diphenylmethyloxycarbonyl-5-methyl-s-triazolo[1,5-a]pyrimidin-7-yl)thiomethyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid diphenylmethyl ester (5.0 g) in dichloromethane (170 ml) was added dicyclohexylcarbodiimide (1.4 g), and the mixture was stirred at room temperature for five hours. After filtering off the insoluble matters, the filtrate was concentrated under reduced pressure. The residue was dissolved in ethyl acetate and the insoluble matters were filtered off. The filtrate was washed with brine and dried over anhydrous sodium sulfate. The dried solution was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography, giving 0.73 g (less polar form) and 1.39 g (more polar form) of the objective compounds.

1. filtrationAfter filtering off the insoluble matters
2. concentrationthe filtrate was concentrated under reduced pressure
3. dissolutionThe residue was dissolved in ethyl acetate
4. filtrationthe insoluble matters were filtered off
5. washThe filtrate was washed with brine
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationThe dried solution was concentrated under reduced pressure
8. customthe residue was purified by silica gel column chromatography
9. customgiving 0.73 g (less polar form) and 1.39 g (more polar form) of the objective compounds