| Abstract
| - Ester-containing nitrones, including 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide 5, have beenreported to be robust spin traps for superoxide (O2•-). Using a chiral column, we have been able toisolate the two enantiomers of nitrone 5. With enantiomerically pure nitrone 5a and 5b we exploredwhether one of these isomers was solely responsible for the EPR spectrum of aminoxyl 6. Dataobtained demonstrate that the spin trapping of O2•- by nitrone 5a and nitrone 5b affords theidentical EPR spectra and lifetimes in homogeneous aqueous solution and exhibits the same ratioof cis and trans isomers. Quantum chemical modeling in vacuo also finds no difference, aside fromthe expected optical activity, arising from the difference in stereochemistry.
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