Definition of penicillanic acid in English:

penicillanic acid

noun

Chemistry
  • A crystalline compound, C₈H₁₁NO₂S, whose bicyclic molecular structure is the nucleus of the penicillins and consists of a β-lactam ring fused to a molecule of 5,5-dimethylthiazolidine-4-carboxylic acid.

Origin

1950s.