Dichloromethane → (6R,7R)-7-amino-3-[[[5-(hydroxycarbamoyl)-2-(hydroxymethyl)-s-triazolo[1,5-a]pyrimidin-7-yl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

N-Hydroxy-2-(hydroxymethyl)-7-mercapto-s-triazolo[1,5-a]pyrimidine-5-carboxamide (190 mg) (0.79 mmol) and 193 mg (0.71 mmol) of 7-amino-cephalosporanic acid are suspended in 20 ml of sulpholane/dichloromethane (1:1 v/v). 4.2 ml of boron trifluoride diethyl etherate are added thereto at 0° C. The mixture is stirred at 0° C. for 2 hours and at room temperature for 20 hours. 80 ml of dichloromethane are added. The precipitated material is separated and dissolved in water. The mixture is adjusted to pH 4 by the addition of saturated aqueous sodium hydrogen carbonate solution. The precipitated product is filtered off under suction and washed in sequence with water, ethanol and diethyl ether. There are obtained 130 mg of (6R,7R)-7-amino-3-[[[5-(hydroxycarbamoyl)-2-(hydroxymethyl)-s-triazolo[1,5-a]pyrimidin-7-yl]thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid as a beige powder.

Provenance & Evidence