4-Thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, 6-((((((imino-4-pyridinylmethyl)amino)acetyl)amino)phenylacetyl)amino)-3,3-dimethyl-7-oxo-, monosodium salt, (2S-(2alpha,5alpha,6beta(S*)))- 55162-26-0 CP 33994-2 PIRBENICILLIN SODIUM Pirbencillin sodium Pirbenicillin sodium [USAN] Sodium (2S,5R,6R)-6-((R)-2-(2-(isonicotinimidoylamino)acetamido)-2-phenylacetamido)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo(3.2.0)heptane-2-carboxylate