Circular Dichroism and Absorption Spectra of Monoand Di-Aminoacridines Complexed to DNA

The absorption and circular dichroism spectra of the intercalation complexes with DNA of the 9-aminoacridine chromophore in mono- and bisfunctional forms have been determined in the visible/near-ultraviolet region. The experimental spectra were deconvoluted into contributions from three (It*, n) transitions and the dipole and rotatory strengths of one long-axis and one shortaxis polarized transition were determined for each intercalating species. The experimental results were compared with theoretical calculations of the induced CD of intercalation complexes and a series. of inferences were drawn concerning the geometry of the complexes