Cefazolin IMpurity D

(6R-trans)-3-(acetoxymethyl)-8-oxo-7-(1H-tetrazol-1-ylacetamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

(6R)-3-[(Acetyloxy)methyl]-8-oxo-7α-[[(1H-tetrazol-1-yl)acetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid