(6R,7S)-3-[[[[[[(6R,7S)-2-Carboxy-7-methoxy-8-oxo-7-[[2-(thiophen-2-yl)acetyl] amino]-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methyl]oxy]carbamoyl]oxy]methyl]-7-methoxy-8-oxo-7-[[2-(thiophen-2-yl)acetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid