Cefoxitin (sodium salt) is a second generation cephalosporin antibiotic that was used to treat a wide range of gram-negative and gram-positive bacteria [1][2].

Cefoxitin, 3-carbamoyloxymethyl-7-a-methoxy-7- [2-(2-thienyl)acetamido]-3-cephem-4-carboxylic acid, is a semisynthetic cephamycin antibiotic with broad-spectrum activity. Cefoxitin is also active in vivo against a wide variety of bacteria including penicillin-resistant staphylococci and effective against gram-negative organisms including strains of indole-positive Proteus [1].

In mice, cefoxitin was more active against the cephalosporin-sensitive gram-negative bacteria, strains of E.coli, indole-producing Proteus, and Serratia, and the lactamase producing 2646. Cefoxitin was degraded by the lactamase of E. cloacae at a much slower rate than are the cephalosporins. In pharmacological studies, cefoxitin was found in sera and detected in urine samples in amounts greater than those of cephalothin and less than those of cephaloridine [1].

References:
[1].  Miller AK, Celozzi E, Kong Y, et al. Cefoxitin, a semisynthetic cephamycin antibiotic: in vivo evaluation. Antimicrob Agents Chemother. 1974 Jan;5(1):33-7.
[2].  Jacoby GA. AmpC beta-lactamases. Clin Microbiol Rev.2009 Jan;22(1):161-82.