(6R,7R)-7-[2-(2-amino-1,3-thiazol-4-yl)-2(Z)-(1-carboxy-1-methylethyloxyimino)acetamido]-8-oxo-3-(1-pyridiniumylmethyl)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate pentahydrate