5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid,3-(chloromethyl)-7-[[(2Z)-[5-[[(1,1-dimethylethoxy)carbonyl]amino]-1,2,4-thiadiazol-3-yl](ethoxyimino)acetyl]amino]-8-oxo-,(4-methoxyphenyl)methyl ester, (6R,7R)-