Mefoxin
Cefoxitin(1-) is a cephalosporin carboxylic acid anion having methoxy, 2-thienylacetamido and carbamoyloxymethyl side-groups, formed by proton loss from the carboxy group of the semisynthetic cephamycin antibiotic cefoxitin. It is a conjugate base of a cefoxitin.