Deuterated analogues of the free radical trap DEPMPO:: synthesis and, EPR studies

Three analogues of 5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide (DEPMPO, 1) labelled with two (1-d(2)), five (1-d(5)) or seven (1-d(7)) H-2 were synthesized and used to trap the tert-butylperoxyl radical. The EPR spectra of 1-d(2)-OOBu' and 1-d(7)-OOBu' spin adducts exhibited more straightforward patterns and better signal to noise ratio than those obtained with 1 or 1-d(5). The use of the easily available 1-d(2) as spin trap could help significantly the analysis of the EPR signals when the signal of either superoxide or alkylperoxyl spin adduct is superimposed with the signals of other spin adducts.