Frank, N. L.; Meade,* T. J. 5’ Modification Of Duplex DNA With A Ruthenium Electron Donor-Acceptor Pair Using Solid-Phase DNA Synthesis Inorg. Chem. 2003 42, 1039-1044. (FEB 24 2003) DOI: 10.1021/ic025567q.
Incorporation of metallated nucleosides into DNA through covalent modification is crucial to measurement of thermal electron-transfer rates and the dependence of these rates with structure, distance, and position. Here, we report the first synthesis of an electron donor-acceptor pair of 5' metallonucleosides and their subsequent incorporation into oligonucleotides using solid-phase DNA synthesis. Metal-containing oligonucleotides were prepared via 5' modified phosporamidites containing acceptor and donor ruthenium complexes. The electronic structures of the metal complexes are retained upon incorporation into duplex DNA, and the stability of the resultant duplexes is higher than the parent duplexes, providing a valuable strategy for investigations of thermal charge transfer processes in DNA.