5-(DIETHOXYPHOSPHORYL)-5-METHYL-1-PYRROLINE N-OXIDE - A NEW EFFICIENTPHOSPHORYLATED NITRONE FOR THE IN-VITRO AND IN-VIVO SPIN-TRAPPING OF OXYGEN-CENTERED RADICALS

5-(Diethoxyphosphoryl)-5-methyl-1-pyrroline N-oxide (DEPMPO, 2), a new spin trap, has been synthesized via a two-step synthetic route, and i ts ability to spin trap oxy radicals in biological milieu has been add ressed. The in vitro spin trapping of hydroxyl and superoxide radicals was investigated in a phosphate buffer 0.1 M, and the hyperfine coupl ing constants of the spin adducts were determined. The rates of spin t rapping of hydroxyl and superoxide radicals with 2 were found to be cl ose to those reported for 5,5-dimethyl-1-pyrroline N-oxide (DMPO). How ever, the DEPMPO-superoxide spin adduct was shown to be significantly more persistent (15 times at pH 7) than the DMPO-superoxide spin adduc t. Using 2 as a spin trap, the production of superoxide has been clear ly characterized during the reperfusion of ischemic isolated rat heart s.