(6r,7r)-7-{[(2z)-2-(2-amino-1,3-thiazol-4-yl)-2-{[(2-carboxy-2-propanyl)oxy]imino}acetyl]amino}-2-carboxy-3-{[(1-methyl-4-pyridiniumyl)sulfanyl]methyl}-8-oxo-5-thionia-1-azabicyclo[4.2.0]oct-2-en-5-olate