37787-59-0

Upstream product

• 37787-58-9 (6R)-3-methylene-8-oxo-7t-(2-phenoxy-acetylamino)-(6rH)-5-thia-1-aza-bicyclo[4.2.0]octane-2c-carboxylic acid methyl ester 
• 40849-60-3 7-Phenoxyacetamido-3-exo-methylene cepham 
• 80628-86-0 methyl (1S,6R,7R)-3-bromomethyl-1-oxo-7-phenoxyacetamido-3-cephem-4-carboxylate 

Downstream Products

• 37787-63-6 methyl 7β-(phenoxyacetylamino)-3-deacetoxycephalosporanate 1,1-dioxide 
• 37787-60-3 (6R)-3-methyl-5t,8-dioxo-7t-(2-phenoxy-acetylamino)-(6rH)-5λ⁴-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid methyl ester 

Relevant academic research and scientific papers

Process for the preparation of 3-exomethylene cepham derivatives

A process is provided for the preparation of 3-methylene and 3-halomethylene cepham derivatives via 3-phosphoniomethyl-3-cephem derivatives, which in turn can be prepared from 3-halomethyl-3-cephem derivatives. The preparation can be carried out with or without isolating the intermediate phosphonium cephem compounds. The 3-methylene and 3-halomethylene cepham derivatives and in particular the 1-oxo and 1,1-dioxo cepham compounds are also prepared by reducing a 3-halomethyl-3-cephem derivative with activated metal, preferably zinc or magnesium.