thienamycin

Thienamycin is a beta-lactam antibiotic of the carbapenem class. It was the first discovered member of this class and served as the lead structure for later carbapenems used in medicine.

Thienamycin is produced naturally by certain Streptomyces species. Its discovery in the 1980s highlighted the carbapenem core, a structural motif that grants broad-spectrum activity and resistance to some beta-lactamases.

However, thienamycin is chemically unstable and difficult to formulate, which limited its direct therapeutic use. This instability prompted medicinal chemists to develop more stable derivatives inspired by its scaffold, including imipenem, meropenem, and other carbapenems.

In clinical medicine, imipenem was the first carbapenem to reach the market (in combination with cilastatin to prevent renal degradation), followed by further derivatives with improved pharmacokinetic properties. Thienamycin itself is now primarily of historical and medicinal chemistry interest as the natural prototype of the carbapenem class.