Pyridinium, 1-((2-carboxy-8-oxo-7-((2-thienylacetyl)amino)-5-thia-1-azabicyclo(4.2.0)oct-2-en-3-yl)methyl)-, inner salt, (6R-trans)-
(6R,7R)-8-oxo-3-(pyridin-1-ium-1-ylmethyl)- 7-[(2-thiophen-2-ylacetyl)amino]-5-thia-1- azabicyclo[4.2.0]oct-2-ene-2-carboxylate