Ampicillin is a beta lactam antibiotic that is used extensively to treat bacterial infections. Until the introduction of ampicillin pencillin therapies had been only effective against gram positive organisms. Ampicillin demonstrated activity against gram negative bacteria.
Ampicillin is produced by the chemical synthesis of phenyl glycine methyl ester (PGME) with 6-amino penicillanic acid.
Chloramphenicol is a man-made antibiotic. It slows the growth of bacteria by preventing them from producing important proteins that they need to survive. It is considered to be a broad-spectrum antibiotic, alongside the tetracyclines. Chloramphenicol is effective against a wide variety of Gram-positive and Gram-negative bacteria, including most anaerobic organisms. The original indication of chloramphenicol was in the treatment of typhoid. Chloramphenicol may be used as a second-line agent in the treatment of tetracycline resistant cholera. It is active against three main bacterial causes of meningitis: Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae.
Tetracycline is a broad-spectrum polyketide antibiotic produced by the Streptomyces genus of Actinobacteria indicated for use against many bacterial infections. It is a protein synthesis inhibitor. It is commonly used to treat acne today. Tetracycline is also used to treat many different bacterial infections, such as urinary tract infections, acne, gonorrhea, chlamydia, and others.
Streptomycin is an antibiotic (antimycobacterial) drug, the first of a class of drugs called aminoglycosides to be discovered, and it was the first cure for tuberculosis. It is derived from the actinobacterium Streptomyces griseus.
Streptomycin is a bactericidal antibiotic. Streptomycin is a broad spectrum aminoglycoside antibiotic typically used for treatment of active tuberculosis, always in combination with other antituberculosis agents. Streptomycin is usually used in combination with agents that are known to be hepatotoxic.