Pyridine → HCID 131715887, compound

Participants

Reaction Conditions

Reaction Steps

In 50 ml of dry dichloromethane was dissolved 1.70 g (2.88 mM) of p-methoxybenzyl 7β-phenylacetamido-3-(2-chloroacetyloxy)ethylthio-3-cephem-4-carboxylate, and the solution was cooled to -50° C. To the solution were added 0.706 ml (8.64 mM) of pyridine and 1.196 g (5.76 mM) of phosphorus pentachloride, the reaction temperature of the mixture was raised to 20° C. for a period of one hour, and the mixture was stirred at the same temperature for one hour. Then, the reaction mixture was cooled to -50° C., 10 ml of dry methanol was added, and the temperature of the mixture was raised to 0° C. for a period of one hour. To the reaction mixture cooled to -5° C. was added 10 ml of water, and the mixture was stirred under ice-cooling for 40 minutes. The mixture was made neutral by addition of a saturated aqueous sodium bicarbonate solution, the organic layer was washed with a saturated aqueous sodium chloride solution (10 ml×3) and dried over anhydrous magnesium sulfate. The solvent was evaporated, and the residue was purified by silica gel column chromatography (eluent, dichloromethane) to give 1.22 g of p-methoxybenzyl 7β-amino-3-(2-chloroacetyloxy)ethylthio-3-cephem-4-carboxylate.

Provenance & Evidence