Diazomethane → HCID 70604184, compound

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Reaction Steps

The 3-hydroxy-3-cephem ester can then be converted to a 3-alkoxy-3-cephem ester or to a 3-halo-3-cephem ester. For example, 4-nitrobenzyl 7-phenoxyacetamido-3-hydroxy-3-cephem-4-carboxylate is allowed to react in an inert solvent with diazomethane to form 4-nitrobenzyl 7-phenoxyacetamido-3-methoxy-3-cephem-4-carboxylate. The 4-nitrobenzyl group is removed by catalytic hydrogenolysis over palladium on carbon catalyst to provide the antibiotic compound 7-phenoxyacetamido-3-methoxy-3-cephem-4-carboxylic acid. These 3-methoxy-3-cephem compounds are highly active antibiotics and are fully disclosed in my copending applications Ser. Nos. 310,190 and 310,191, filed Nov. 28. 1972 now U.S. Pat. Nos. 3,917,588 and 3,917,587, respectively, both issued Nov. 4, 1975.

Provenance & Evidence