Non-mutagenic nitroheterocycles. The lack of correlation between bacterial mutagenicity and one-electron reduction potential

The bacterial mutagenicity (Ames test) and the one-electron reduction potential for several nitropyridines, nitropyrazines and nitropyrimidines were determined. It was found that, although these nitroheterocycles underwent one-electron reduction more easily than metronidazole, they were not mutagenic in the Ames test. Six-membered ring nitroheterocycles, will, in general, exhibit diminished mutagenic potential compared to five-membered ring nitroheterocycles, and it is postulated that this effect is due to differences in the electronic nature and potential chemical reactivity of their respective nitrenium ions.