The title compound was prepared via a modification of the synthesis described in U.S. Pat. No. 3,985,737. A solution of 0.51 g (0.001 mole) of diphenylmethyl 7-phenoxyacetamido-3 -hydroxy-3-cephem- 4-carboxylate in 5 mL of acetonitrile was cooled to 0° C. under a nitrogen atmosphere. Then 0.030 g (0.001 mole) of sodium hydride (80% in mineral oil) was added resulting in hydrogen evolution. The reaction mixture was stirred at 0° C. for 5 minutes, and 0.229 g (0.009 mole) of 4-bromobenzenesulfonyl chloride was added. The cooling bath was removed, and the reaction mix stirred at room temperature for 19 hours. The reaction mixture was filtered and the filtrate carbon treated. The carbon was removed followed by the solvent to leave a foam residue. The residue was crystallized from 1-propanol to yield 0.398 g (54%) of the title compound.
