One of the principal themes of bioinorganic chemistry is the synthesis of metal complexes that have the ability to mimic the functional properties of natural metalloproteins. Proteins, some vitamins and enzymes contain metal ions in their structure involving macromolecular ligands. The chemistry of metal complexes with multi dentate ligands having delocalized pi-orbitals, such as Schiff bases or porphyrins has recently gained more attention because of their use as in medicinal field.