Additivity rule holds in the hydrogen transfer reactivity of unsaturated fatty acids with a peroxyl radical: mechanistic insight into lipoxygenase.

A simple additivity rule holds in the hydrogen transfer reactivity of unsaturated fatty acids with cumylperoxyl radical, which is expressed by the additive contributions of the reactivity of active hydrogens from the 1,4-pentadiene subunit and those of the allylic subunit; the kinetic isotope effect on the hydrogen transfer reactions (KIE = 6.1) is significantly smaller than that observed for lipoxygenase (KIE = 81).