Pharma & Specialty Chemical Standards

Cefdinir, IUPAC name (6R,7R)-7-[(Z)-2-(methylthio)acetylamino]-3-vinyl-3-cephem-4-carboxylic acid, is a third-generation cephalosporin antibiotic with molecular formula C₁₆H₁₆N₄O₅S and molecular weight 376.43 g/mol. Structurally, it features a beta-lactam ring fused to a dihydrothiazine ring, with a methylthio and vinyl substituent enhancing stability against beta-lactamases. Therapeutically, it treats respiratory, skin, and otitis media infections by inhibiting bacterial cell wall synthesis via binding to penicillin-binding proteins (PBPs), inducing cell lysis. A white crystalline powder, it exhibits moderate water solubility (pKa ~3.5) and oral bioavailability due to its lipophilic side chain.