Antimicrobiens

Leptomycin B is a bacterial secondary metabolite, which is derived from the bacterium Streptomyces sp. This compound is a potent nuclear export inhibitor with a mechanism of action that targets and inhibits the export receptor CRM1 (Chromosomal Maintenance 1), also known as Exportin 1. By binding irreversibly to CRM1, Leptomycin B prevents the nuclear export of proteins and RNA, disrupting the nuclear-cytoplasmic transport essential for cell function.

Cyclosporin V is an immunosuppressant medication with action on calcineurin inhibition and is used for preventing organ rejection in transplants and treating autoimmune diseases.

Doripenem is a carbapenem antibiotic with action on bacterial cell wall synthesis and is used for treating complicated bacterial infections like intra-abdominal infections and urinary tract infections.

Nikkomycin Z is an antifungal agent, which is a secondary metabolite isolated from the bacterium Streptomyces tendae. This compound functions as a competitive inhibitor of chitin synthase, an essential enzyme responsible for the synthesis of chitin, a vital component of the fungal cell wall. By inhibiting this enzyme, Nikkomycin Z disrupts the structural integrity of the fungal cell wall, leading to impaired growth and cell lysis in susceptible fungi.

Ceftobiprole medocaril sodium is a broad-spectrum cephalosporin antibiotic, which is a synthetically derived prodrug of ceftobiprole. Upon administration, ceftobiprole medocaril is rapidly converted into its active form, ceftobiprole, by the body's endogenous esterases. The mode of action involves binding to penicillin-binding proteins (PBPs) in the bacterial cell wall, leading to the inhibition of cell wall synthesis and ultimately the death of the bacteria. This action is effective against a wide range of gram-positive and gram-negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae.

Doxorubicin Impurity 2 is a chemical impurity of doxorubicin with no direct therapeutic action but used in research and quality control.

Oleandomycin is a macrolide antibiotic, which is derived from the bacterium *Streptomyces antibioticus*. This antibiotic functions by binding to the 50S subunit of the bacterial ribosome, thereby inhibiting protein synthesis. The interruption of this essential process ultimately leads to the cessation of bacterial growth and replication.