Dicyclohexylcarbodiimide → HCID 16166018, compound

Participants

Reaction Steps

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.

Provenance & Evidence