Antibiotics
1- Penicillins
Penicillins contain a P-lactam nucleus that when cleaved by a P-lactamase enzyme (penicillinase) produces penicilloic acid derivatives that are inactive but may act as the antigenic determinants.
Penicillins are poorly soluble, weak organic acids that are administered parenterally either as suspensions in water or oil, or as water-soluble salts.