Synthesis of nucleoside mono- and triphosphates bearing oligopyridine ligands, their incorporation into DNA and complexation with transition metals

Modified nucleoside mono- (dARMPs and dCRMPs) and triphosphates (dARTPs and dCRTPs) bearing bipyridine or terpyridine ligands attached viaacetylene linker were prepared by single-step aqueous-phase Sonogashira cross-coupling of 7-iodo-7-deaza-dAMP or -dATP, and 5-iodo-dCMP or -dCTP with the corresponding bipyridine- or terpyridine-linked acetylenes. The modified dNRTPs were successfully incorporated into the oligonucleotides by primer extension experiment (PEX) using different DNA polymerases and the PEX products were used for post-synthetic complexation with Fe2+.