Application of Molecular Orbital Theory to Biological chemistry (). Interactions of Chemical Carcinogens with DNA Bases

[摘要] The interactions of chemical carcinogens, such as polycyclic aromatic hydrocarbons, dimethylaminoazobenzene (DAB) and its derivatives and heterocyclic compounds with tissue components, especially with deoxyribonucleic acid (DNA), were examined by means of simple Huckel method. Assuming that the formations of a loose molecular complex between the carcinogens and the tissue components are the first step of chemical carcinogenesis, the most proble orientation between the chemical carcinogens and adenine-thymine (A=T) pair or guanine-cytosine (G¡ÕC) pair is determined. It has been found that, in the case of the formation of molecular complex between chemical carcinogens and A=T pair, the two atoms of K-region of the carcinogens and the atom of L-region in the proximity of their K-region are combined correspondingly with C-l' carbon atom in the sugar that is attached to thymine, N-1 nitrogen atom and C-5 carbon atom in the thymine part of A=T pair, while, in the case of that between the carcinogens and G¡ÕC pair, the above three atoms of the carcinogens are combined correspondingly with C-8 carbon atom, N-9 nitrogen atom and N-3 nitrogen atom in the guanine part of G¡ÕC pair.

[学科分类] 化学（综合）