Quantumchemical structure of carcinogenic benz[c]acridines.

Resonance energies, circuit resonance energies and bond currents of benz[c]acridines were calculated by Aihara's IRE theory. Consequently, it was shown that these compounds had very stable aromatic characters with positive resonance energies and that the resonance energies per pi-electron values for the compounds with lack of the double bond corresponding to the K-region from parent skeleton were more stable than those of their parent compounds. Carcinogenic activity of the compounds was related to the charge at QK, QN and QL and high electron density on HOMO orbital.