DNA-PHOTOCLEAVAGE ACTIVITIES OF VANADIUM(V)-PEROXO COMPLEXES

The DNA-photocleavage activities (at 365 nm) of 15 vanadium(V)−peroxo complexes were examined. Singlet oxygen was implicated as the species responsible for the DNA scission. The singlet oxygen was shown to be produced from the photolysis of the vanadium(V)−peroxo complex using a singlet oxygen EPR spin trap, 2,2,6,6-tetramethyl-4-piperidone. A mechanism for the photolysis of the [VO(O_2)_2(bpy)]- anion at neutral pH has been proposed.