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Chloramphenicol is a venerable antibiotic that was isolated from the soil bacterium Streptomyces venezuelae in the late 1940s by researchers at Parke鈥揇avis (Detroit), the University of Illinois (Urbana鈥揅hampaign), and Yale University (New Haven, CT). It was originally called chloromycetin.
In July 1949, the Parke鈥揇avis team published the , which then was given the generic name chloramphenicol; Parke鈥揇avis adopted Chloromycetin as its trade name. The group simultaneously announced a . It was the first totally synthetic antibiotic.
Over the years, chloramphenicol has been used to treat conjunctivitis, meningitis, cholera, and typhoid fever. It is active against bacteria such as Escherichia coli, Staphylococcus spp., and Salmonella spp.
Chloramphenicol can produce some serious adverse effects, including aplastic anemia, neurotoxicity, and some cancers. In 1991, the United States discontinued the use of the oral formulation because of its association with aplastic anemia. In 2007, the World Health Organization classified it as a probable human carcinogen.
Chloramphenicol is still being used in the United States and other countries as an injectable. It is administered intravenously as the more water-soluble prodrug chloramphenicol monosuccinate. Intravenous dosages are greater than oral ones because much of the ester is eliminated before the body can hydrolyze it. Another prodrug, chloramphenicol palmitate, is given orally, but like the parent compound, it is no longer approved for use in the United States.
Chloramphenicol聽hazard information
Hazard class* | Hazard statement | |
---|---|---|
Carcinogenicity, category 2 | H351鈥擲uspected of causing cancer | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals.聽
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Chloramphenicol fast facts
CAS Reg. No. | 56-75-7 |
nomenclature | Acetamide, 2, 2-dichloro-N-[(1R,2R)-2-hydroxy-1-(hydroxymethyl)-2-(4-nitrophenyl)ethyl]- |
Empirical formula | C11H12Cl2N2O5 |
Molar mass | 323.13 g/mol |
Appearance | White to pale yellow needles, plates, or powder |
Melting point | 150.5鈥�151.5 潞C |
Water solubility | 2.5 g/L |

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