Catechol derived siderophores are the most powerful currently known iron chelators. We have intended tripodal ligands built with o,o' dihydroxy biaryl subunits (A, B, and C). We described antioxidant properties of this new family of iron chelators. Superoxide-dependent hydroxyl radical system was used. Peroxidation of different lipid-containing systems (liposomes, erythrocyte membrane ghosts, tissue homogenates) were also investigated. The antioxidant properties of these new chelators have been related to that of desferrioxamine as a reference compound. In general manner, the results depended mainly on the model used in the assay. However, C presents an antioxidant effect close to that of desferrioxamine.