A Proposed Model of the Interaction of 4-Nitroquinoline 1-Oxide with DNA1

correlations between carcinogenicity and several molecular orbital characteristics were found. All correlations between molecular orbital properties and carcinogenicity were modified by one or more of the following structural factors: (a) the absence of a 4-nitro group, (b) the absence of a 1-oxide group, or (c) the presence of bulky substituents in position 2 or 3 of the quinoline ring. Any of the three factors resulted in either noncarcinogenicity or reduced carcinogenicity. Conformational studies indicated that the 4-nitro group was approximately 60°out of the plane of the quinoline ring and