Relative stabilities of nitrenium ions derived from heterocyclic amine food carcinogens: relationship to mutagenicity.

The bacterial mutagenicities of a wide variety of complex heteroaromatic amine mutagens and carcinogens present in cooked foods are approximately related to the stabilities of the corresponding nitrenium ions through equations of the kind: log(m) = a delta delta H + b. The stabilities of the nitrenium ions (delta delta H) were computed using the semiempirical AM1 molecular orbital procedure. Parallel calculations of the energies, charge distributions and geometries of simple model compounds provides a qualitative framework within which the stabilities of the nitrenium ions derived from the food carcinogens can be easily understood.