has role cephalosporin tetrazoles antibacterial drug thiadiazoles cefazolin A first-generation cephalosporin compound having [(5-methyl-1,3,4-thiadiazol-2-yl)sulfanyl]methyl and (1<em>H</em>-tetrazol-1-ylacetyl)amino side-groups at positions 3 and 7 respectively. Cefamezin CHEBI:474053 chebi_ontology (6R,7R)-3-{[(5-methyl-1,3,4-thiadiazol-2-yl)sulfanyl]methyl}-8-oxo-7-[(1H-tetrazol-1-ylacetyl)amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid CEZ Cephazolidin Cephazoline Cephamezine CHEBI:3482 Cephazolin cefazolin(1-) beta-lactam antibiotic allergen