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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Reversal of a Single Base-Pair Step Controls Guanine Photo-Oxidation by an Intercalating Ruthenium(II)
Páraic M Keane1,2, Fergus E Poynton3,4, James P Hall5,6
1School of Chemistry, Trinity College, Dublin 2 (Ireland). keanepa@tcd.ie.
Abstract:
Small changes in DNA sequence can often have major biological effects. Here the rates and yields of guanine photo-oxidation by Λ-[Ru(TAP)2(dppz)](2+) have been compared in 5'-{CCGGATCCGG}2 and 5'-{CCGGTACCGG}2 using pico/nanosecond transient visible and time-resolved IR (TRIR) spectroscopy. The inefficiency of electron transfer in the TA sequence is consistent with the 5'-TA-3' versus 5'-AT-3' binding preference predicted by X-ray crystallography. The TRIR spectra also reveal the differences in binding sites in the two oligonucleotides.
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