Solvent-independent antioxidant activity from thermally generated carbon-centered radical antioxidants.

A new and unusual class of chain-breaking antioxidants has been discovered, where the actual antioxidant is, paradoxically, a carbon-centered radical. Properties of these molecules are currently being studied. The solvent dependence on antioxidant activity of the HP-136 dimer has been measured, in solvents of varying H-bond accepting ability, by the inhibited oxygen uptake (IOU) method. As anticipated, the HP-136 dimer was found to show much less solvent effect on antioxidant activity than a representative phenolic antioxidant.