Synthesis of photochemically active complexes for DNA recognition and binding

Abstract

The objective of this thesis is to synthesize and examine the photophysical and structural properties of 3-(pyridin-2-yl)imidazo[1,5-a]pyridine (P) and 3-(pyridin-2-yl)imidazo [1,5-a]pyridine (IQ) based cations and their potential use as DNA binding agents. The P ligand was aimed to compare with the IQ ligand as they have similar structures. Two series of compounds were synthesized; one series comprising organic cations, including PC2, PC3, PC4, IQC2 and IQC3. The other one contains ruthenium complexes Ru(bpy)2P, Ru(bpy)2IQ and Ru(P)3). Compounds were prepared as Cl-, Br- and/or PF6- salts. All compounds were characterized by NMR, UV-vis, luminescescence and electrochemistry, when applicable. The results show that P and IQ based organic cations have similar electrochemical properties, and may be candidates for guanine photo-oxidation. However, [Ru(bpy)2P](PF6)2, [Ru(bpy)2IQ](PF6)2 and [Ru(P)3](PF6)2 do not seem to have reduction potentials in the excited states that are appropriate for nucleic base photo-oxidation.