(6R,7R)-7-[[(2Z)-2-(2-Amino-4-thiazolyl-13C,15N2)-2-[(carboxymethoxy)imino]acetyl]amino]-3-ethenyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic Acid,"Labelled Cefixime . Orally active, third generation cephalosporin antibiotic.;Labeled Cefixime, intended for use as an internal standard for the quantification of Cefixime by GC- or LC-mass spectrometry.",Cefixime Stable Isotopes