1 CLS Cephalothin 1.000 2 CFX Cefoxitin 0.862 3 KEF Cefuroxime (oct-3-ene form) 0.774 4 KOV (6r,7r)-3-[(carbamoyloxy)methyl]-7-{[(2z)-2-(furan-2-yl)-2-(methoxyimino)acetyl]amino}-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid 0.774