Radical productions and pi-spin density by UHF/PM3 method on benz[c]acridines and benzo[a]phenothiazines

On the calculated pi-spin density (rho pi) of benz[c]acridines [1-12], benz[c]acridines [2,8-12] with alternately value of pi-spin density (rho pi) on angular ring, large negative pi-spin density at C-1 and C-3 positions and large positive pi-spin density at C-2 and C-4 positions indicates their carcinogenicity, except for 7-methylbenz[c]acridine [7]. Benz[c]acridines [1,3-6] which do not follow were not carcinogenic. Radical producing benzo[a]phenothiazines [13-16] and non-radical producing benzo[a]phenothiazines [17-19] gave calculated pi-spin density (rho pi) which was positive in radical producing benzo[a]phenothiazines [13-16] at N-12 position, and had the opposite pi-spin density in non-radical producing benzo[a]phenothiazines [17-19].