Synthesis and photophysical properties of 7-deaza-2′-deoxyadenosines bearing bipyridine ligands and their Ru(II)-complexes in position 7

The synthesis of the title 7-deazaadenine 2'-deoxyribonucleosides bearing bipyridine, phenanthroline or terpyridine ligands linked to position 7 via an acetylene or phenylene spacer is reported based on aqueous cross-coupling reactions of unprotected 7-iodo-7-deaza-2'-deoxyadenosine with ligand-functionalized acetylenes or boronic acids. The aqueous cross-coupling with acetylene or boronate building blocks containing the Ru(bpy)(3)-type of complex gave the corresponding Ru-containing nucleosides. Photophysical and electrochemical properties were studied and the most efficient type of complex was selected for future luminescent and redox labelling of DNA. The title nucleosides also showed some cytostatic and anti-HCV activities.