Antioxidant properties of α‐tocopherol derivatives and relationship of antioxidant activity to biological activity

A series of α‐tocopherol analogs substituted at the 5‐methyl group were evaluated for their ability to protect β‐carotene dissolved in hydrogenated, tocopherol‐stripped corn oil from air oxidation. These results were compared with the ability of these compounds to prevent the development of dietary necrotic liver degeneration in rats and vitamin E deficiency‐induced muscular dystrophy in rabbits. Although a good correlation was seen between the antioxidant activities of some of the compounds and their biological activities, in the case of other compounds the correlation was poor. The importance of the phytyl side chain of the tocopherols and their derivatives for their antioxidant activities was evident from these studies.