Spectrochemical and Biological Evaluation of Axially Substituted Zirconium(IV) meso-Tetra(4-methoxyphenyl)porphyrins

New Zr(IV) macrocyclic complexes of meso-5,10,15,20-tetra(4-methoxyphenyl)porphyrin (H2TMP) with general formula [5-XSAZr(TMP), 5-XSA = salicylate (5-HSA), 5-sulfosalicylate (5-SSA), 5-aminosalicylate (5-ASA), 5-chlorosalicylate (5-CSA), 5-fluorosalicylate (5-FSA), and 5-nitrosalicylate (5-NSA)] have been prepared when Cl2Zr(TMP) has been allowed to react with the corresponding salicylate. The complexes have been characterized by elemental analysis, spectroscopic studies (UV-vis, IR, 1H NMR) and mass spectrometry as well as fluorescence spectroscopy. The data from spectroscopic and analytical studies revealed a six coordinate geometry around the metal with N4 tetradendate donor sites in addition to one bidendate salicylate occupying the other two sites. Cyclic voltammograms of axially ligated zirconium(IV) porphyrins show three waves for the complexes studied which can be attributed to one-electron processes 5-XSAZr(TMP)0/−1, 5-XSAZr(TMP)X1+/0, and 5-XSAZr(TMP)2+/+1. The thermal properties of complexes Cl2Zr(TMP) and two axially ligated complexes SAZr(TMP) and 5-NSAZr(TMP) have been studied by TG and DTA to determine the thermal stability of these complexes. In addition, we have tested H2TMP and all complexes synthesized for antibacterial and antioxidant activity. The results have shown that all zirconium(IV) porphyrin have higher antimicrobial activity as compared with free ligand. The in vitro anticancer activity of some selected complexes against human lung (A-549), Glioblastoma (T98G), Breast (MCF-7), and prostrate (PC-3) cell line have been determined using sulforhodamine B dye assay.