Radical trapping properties of 3-aryl-2H-benzo[1,4]oxazin-4-oxides.
A series of 3-aryl-2H-benzo[1,4]oxazin-4-oxides was prepared, and their ability to trap free radicals was investigated by EPR spectroscopy. In organic solvents, these compounds were able to efficiently scavenge all carbon- and oxygen-centered radicals tested, giving very persistent aminoxyls, except with superoxide anion whose spin adducts were unstable. The main feature of these nitrones as spin traps lies in the possibility to recognize the initial radical trapped. In fact, besides a g-factor and aminoxyl nitrogen EPR coupling constant dependence on the species trapped, the EPR spectra also show different patterns due to hyperfine splittings characteristic of the radical scavenged. This last important feature was investigated by means of density functional theory calculations.
Astolfi
Paola
P
Dipartimento di Scienze e Tecnologie Chimiche, Università Politecnica delle Marche, via Brecce Bianche, I-60131, Ancona, Italy.
Marini
Milvia
M
Stipa
Pierluigi
P
D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D005609:Free Radicals / Q000138:chemical synthesis / Q000737:chemistry; D008956:Models, Chemical; D015394:Molecular Structure; D009589:Nitrogen Oxides / Q000138:chemical synthesis / Q000737:chemistry; D010078:Oxazines / Q000737:chemistry*; D011789:Quantum Theory; D019097:Spin Trapping; D013329:Structure-Activity Relationship
D005609:Free Radicals; D009589:Nitrogen Oxides; D010078:Oxazines; C015388:nitrones