Dual stimulatory and inhibitory effects of fluorine-substitution on mutagenicity: an extension of the enamine epoxide theory for activation of the quinoline nucleus.

Nineteen mono- and di-fluorinated derivatives of quinoline, 1,7-phenanthroline, 1,10-phenanthroline, benzo[h]quinoline, and benzo[f]quinoline were subjected to analysis of their structure-mutagenicity relationships. For this purpose, six new fluorinated derivatives were synthesized. The results support that the enamine epoxide structure of the pyridine moiety, as well as the bay-region epoxide structure, is responsible for mutagenicity. Formation of K-region epoxides might involve a detoxification process rather than mutagenic activation.