potassium;(2S,5R,6R)-6-[[2,2-dideuterio-2-(2,3,4,5,6-pentadeuteriophenyl)acetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate,(2S,5R,6R)-3,3-Dimethyl-7-oxo-6-[(2-phenylacetyl-d7)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic Acid Potassium Salt,Penicillin Stable Isotopes