Chemical Name: (6R,7R)-7-Amino-3-[(1-methylpyrrolidinio)methyl]-8-oxo-5-thia-1-azabicyclo [4.2.0]oct-2-ene-2-carboxylate (as per EP); 1-{[(6R,7R)-7-Amino-2-carboxy-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methyl}-1-methylpyrrolidin-1-ium chloride (as per USP)