abstract |
Cephalosporin sulfoxides are reduced to the corresponding cephalosporin with acyl bromides, e.g., acetyl bromide, in the presence of a bromine scavenger, e.g., an olefin, acetylene, phenol, phenol ether, or an organophosphite. For example, p-nitrobenzyl 7-phenoxyacetamido-3-methyl-3-cephem-4-carboxylate sulfoxide is reduced with acetyl bromide in the presence of amylene to p-nitrobenzyl 7-phenoxyacetamido-3-methyl-3-cephem-4-carboxylate. |