(6R,7R)-7-amino-3-(((5-methyl-1,3,4-thiadiazol-2-yl)thio)methyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;7-Amino-3-[(2-methyl-1,3,4-thiadiazol-5-ylthio)methyl]-3-cephem-4-carboxylic Acid; (6R-trans)-7-Amino-3-[[(5-methyl-1,3,4-thiadiazol-2-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid; 7-ZACA; Cefazolin EP Impurity A;7-Amino-3-[(5-methyl-1,3,4-thiadiazol-2-ylthio)methyl]-3-cephem-4-carboxylic Acid;
