CHLORAMPHENICOL AND ANALOGUES

Organism strain No. of strains tested Susceptibility Chloramphenicol Thiomphenicol Florfenicol 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

Both chloramphenicol and thiamphenicol cause reversible bone marrow suppression (9). The irreversible, often fatal, aplastic anemia, however, is only seen for chloramphenicol (9). This rare (1 in 10,000—45,000) chloramphenicol toxicity has been linked to the nitroaromatic function (1,9). Thiamphenicol, which is less toxic than chloramphenicol in regard to aplastic anemia, lacks potency as can be seen in Table 1, and thiamphenicol has never found much usage in the United States. An analogue of thiamphenicol having antimicrobial potencies equivalent to chloramphenicol was sought. Florfenicol (2) was selected for further development from a number of closely related stmctures. 

3- propanediol moiety was absolutely essential for amphenicol-type activity (20,21). 

Stmcture-activity and mechanism of action studies indicate that the requirements for chloramphenicol activity are the D-threo-configuration, the 

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Table 3. Activity of Chloramphenicol and Analogues Against Chloramphenicol-Sensitive and -Resistant Organisms...

ANTIBIOTICS - CHLORAMPHENICOL AND ANALOGUES] (Vol2) Proteus valgaris Napolitano... 

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