Synthesis of novel aromatic nitroxides as potential DNA intercalators. An EPR spectroscopical and DFT computational study.
The synthesis and electron paramagnetic resonance (EPR) spectroscopic properties of three novel aromatic nitroxides and potential DNA intercalators, the carbazole-based 3,6-dimethylcarbazole-9-oxyl, as well as the acridane-based 9-acridanylidenemalonitrile-10-oxyl and 9-ethylacridanylidenecyanoacetate-10-oxyl, are described. The two acridane-based nitroxides can be isolated and are stable in solution as well as in the solid state for several days. Continuous wave X-band EPR measurements and density functional theory (DFT) calculations demonstrated that the spin density is delocalized over the whole molecule in all three cases. Furthermore, the DFT calculations provided insight into the molecular and electronic structures of these nitroxides and yielded hyperfine coupling constants which are in very good agreement with the experimental data allowing therefore an unambiguous assignment of the hyperfine couplings.
Beyer
Mario
M
Institut für Physikalische und Theoretische Chemie, Johann Wolfgang Goethe-Universität, Marie-Curie-Strasse 11, D-60439 Frankfurt am Main, Germany.
Fritscher
Jörg
J
Feresin
Emiliano
E
Schiemann
Olav
O
D002227:Carbazoles / Q000138:chemical synthesis*; D002384:Catalysis; D004247:DNA / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D007202:Indicators and Reagents; D007364:Intercalating Agents / Q000138:chemical synthesis*; D008968:Molecular Conformation; D015394:Molecular Structure; D009589:Nitrogen Oxides / Q000138:chemical synthesis*
D002227:Carbazoles; D007202:Indicators and Reagents; D007364:Intercalating Agents; D009589:Nitrogen Oxides; D004247:DNA; C039900:nitroxyl