Monobactams are bacterially-produced monocyclic β-lactam antibiotics. The β-lactam ring is not fused to another ring, in contrast to most other β-lactams.[1]
Monobactams are narrow-spectrum antibiotics[2] effective only against (strictly or facultatively[3]) aerobic Gram-negativebacilli,[4][5][3] exhibiting a high level of resistance to beta-lactamases of these organisms.[3] Due to their narrow spectrum, monobactams can be used to treat infections by susceptible bacteria without disrupting the patient's microbiota.[2] Monobactams are nevertheless seldom used.[2]