Synthesis Of 7 β-amino-3-nor-3-cephem-4-carboxylic Acid

Ceftizoxime and ceftibuten are the third-generation cephalosporins with potent biological activity against many microbes of both Gram-positive bacteria and Gram-negative bacteria. However, Chinese company has not successfully produced these valuable antibiotics so far. 7-Amino-3-nor-3-cephem-4-carboxylic acid (7-ANCA) is the key intermediate to ceftizoxime and ceftibuten. At present there is no large-scale production of 7-ANCA in China. The reason might be partially due to long reaction sequences and expensive reagents for all known synthetic schemes. Therefore, it is imperative to explore effective synthesis of 7-ANCA.To develop an efficient route to 7-ANCA, all known methods for this compound were collected, and closely scrutinized. A reasonable was proposed as follow with the yet-elusive catalytic decarbonylation as the key step.