Design and Synthesis of Manganese Porphyrins With Tailored Lipophilicity: Investigation of Redox Properties and Superoxide Dismutase Activity

Thirteen new manganese porphyrins and two porphodimethenes bearing one to three different substituents at the meso positions in a variety of architectures have been synthesized. The substituents employed generally are (i) electron-withdrawing to tune the reduction potential to the desirable range (near +0.3 V vs NHE), and/or (ii) lipophilic to target the interior of lipid bilayer membranes and/or the blood-brain barrier. The influence of the substituents on the MnIII/MnII reduction potentials has been characterized, and the superoxide dismutase activity of the compounds has been examined.