One-electron reduction of 2-aminopurine in the aqueous phase. A DFT and pulse radiolysis study.
The electron affinity and the subsequent proton affinity of the electron adducts of 2-aminopurine (abbreviated 2AP) and adenine (A) are calculated with density functional theory (DFT). According to these calculations 2AP*- and A*- have similar thermochemical parameters leading to the conclusion that their reaction pathways should be close to analogous. Using the pulse radiolysis technique 2AP*- is formed by reaction with the hydrated electron (e(-)aq) and the resulting transient absorption spectrum is assigned to 2AP(NH)*. Additionally, it was found, employing the laser flash photolysis technique, that the excited singlet state of 2AP is incapable of oxidizing guanine in the aqueous phase. However, the one-electron oxidized 2AP (2AP*+) has sufficient energy to ionize guanine according to the DFT results in agreement with experimental data from the literature.
Max-Planck-Institut für Strahlenchemie, D-45413 Mülheim, Germany. Johannes.Reynisson@icr.ac.uk
Jóhannes
J
Reynisson
Steen
S
Steenken
D015075:2-Aminopurine / Q000737:chemistry*; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D004583:Electrons; D005609:Free Radicals / Q000737:chemistry; D007834:Lasers; D008956:Models, Chemical; D015394:Molecular Structure; D011675:Pulse Radiolysis; D014867:Water / Q000737:chemistry*
D005609:Free Radicals; D014867:Water; D015075:2-Aminopurine