Sandeep Mewada Pharmacology & medicinal Chemistry

1. Monobactam
• Monobactams are β-lactam
compounds wherein the β-lactam
ring is alone and not fused to
another ring, in contrast to most
other β-lactams.
• They are effective only against
aerobic Gram-negative bacteria.
• (e.g., Neisseria, Pseudomonas).

2. Other examples of monobactams are
•aztreonam.
•tigemonam,
•nocardicin A,
•and tabtoxin.

3. Aztreonam. (The four-membered ring at the bottom
is the β-lactam. There is a second thiazole ring, but it
is not fused to the β-lactam ring.)

4. Tigemonam

5. Adverse effects to monobactams
can include
• skin rash
• and occasional abnormal liver
functions.
• They have no cross-hypersensitivity
reactions with penicillin but like
penicillins can trigger seizures in
patients with history of seizures.