Semi-synthesis of<unk>  from ampicillin. Derived from “the addition of a hydrophilic heterocyclic group to the α-amino group of ampicillin”, the structure consists of a thiazolidine ring conjoined to a β-lactam ring contained within several ring compounds. The addition of this substituent increases the compound's affinity to penicillin-binding protein PBP-3, improving activity against Gram-negative bacteria, and thus broadening its spectrum of activity. Susceptible β-lactamase producing bacteria such as Staphylococcus spp. or Haemophilus influenzae, the combination of tazobactam (which shares a similar structure to sulbactam, another β-lactamase inhibitor), and<unk>  significantly improves the stability of the drug against β-lactamases.
Piperacillin
Cloxacillin
Resistin
Carbenicillin
Cefazolin
Ampicillin
Dicloxacillin
Vancomycin