Ampicillin Impurity 61

(2S,5R,6R) -6- ((R) -2- ((2S,5R,6R) -6- ((R) -2- ((2S,5R,6R) -6- ((R) -2-amino-2-phenylacetamido) -3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxamido) -2-phenylacetamido) -3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxamido) -2-phenylacetamido) -3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid