Cefoselis is a new fourth-generation cephalosporin and was launched
in Japan as a parenteral antibiotic for a variety of infections including
Staphylococcus aureus (particularly the methicillin-resistant MRSA) and
Pseudornonas aeruginosa. It can be prepared in 3 related ways, all using 2-
pyrazolomethyl-3-cephem-4-carboxylic as the key intermediate. In preclinical
studies, Cefolesis had better MIC50s than Ceftazidime against Streptococcus
pneurnoniae or Staphflococcus aureus (methicillin-sensitive MSSA or resistant
MRSA) and showed significant antibacterial activity against Citrobacter and
Enterobacter.
Cefolesis is well tolerated in clinical studies, being eliminated mainly via
glomerular filtration in humans.
