THIAMPHENICOL

Chloramphenicol is a relatively simple structure broad-spectrum antibiotic which is effective against rickettsiae, gram-positive and gram-negative bacteria, and certain spirochetes by inhibiting translation on the 50S ribosomal subunit at the peptidyltransferase step (elongation inhibition). It was originally isolated from a species of streptomyces bacteria and other spirochetes later, but is produced synthetically. Because of its toxicity and side-effect, it should only be used for serious infections in which other medicines do not work; should not be used for colds, flu, other virus infections, sore throats or other minor infections, or to prevent infections. It is used especially in the treatment of typhus and other rickettsial infections and in typhoid, shigellosis, and related enteric diseases. Chloramphenicol is used in biological research of protein synthesis. It is a greenish white or yellowish white needle-like solid; slightly soluble in water and ether; soluble in alcohol; melting point 148-150 C. Its chemical designation is D(-)-threo-2,2-Dichloro-N-[beta-hydroxy-alpha-(hydroxymethyl)- beta-(4-nitrophenyl)ethyl] acetamide or D-(-)-threo-1-(p-nitrophenyl)-2-dichloro acetamido-1,3-propanediol.

Chloramphenicol palmitate: the palmitic ester of chloramphenicol, administered orally.