(6R)-7α-[[(2-Amino-4-thiazolyl)[(Z)-methoxyimino]acetyl]amino]-3-[(1-methylpyrrolidinio)methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid ion
[6R-[(6α,7β(Z)]]-7-[[(2-Amino-4-thiazolyl)(methoxyimino)acetyl]amino]-2-carboxy-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-y1]methy1]-1-methylpyrrolidinium inner salt