Microbial infections prophylaxis

A number of 5-nitro-2-furaldehyde derivatives, called nitrofurans, are used in the treatment and/or prophylaxis of microbial infections, primarily in the urinary tract. Recent evidence suggests that the reduction of the 5-nitro group to the nitro anion results in bacterial toxicity. Intermediate metabolites modify various bacterial macromolecules that affect a variety of biochemical processes (e.g., DNA and RNA synthesis, protein synthesis) this observation may explain the lack of resistance development to these drugs. Evidence also indicates that the nitro anion undergoes recycling with the production of superoxide and other toxic oxygen compounds. It is presumed that the nitrofurans are selectively toxic to microbial cells because in humans, the slower reduction by mammalian cells prevents high serum concentrations. 

Nitroimidazoles were then found to have excellent anti-microbial properties. For example, tinidazole (6.16) is valued for the prophylaxis of anaerobic bacteria] infection of the bowel, before operation, particularly with species of Bacteroides, also for the treatment of such infections (Hunt et al., 1979). It is also effective in the protozoal diseases, amoebiasis, giardiasis, and trichomoniasis. For the anti-protozoaI action ofnitro-heterocycles, see Section 6.3.3. 

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