Synthesis, Characterization and in vitro Biological Activities of Pyrazolylpalladium(II) Complexes towards Selected Strains | Insight Medical Publishing

Four palladium(II) complexes vz. C1, [PdCl2(L1)] (L1 = 3-ferrocenyl-1H-pyrazole), C2, [PdCl2(L2)] (L2 = 3-ferrocenylpyrazolyl-1-methylenepyridine), C3, [PdCl2(L3)] (L3 = 3,5-dimethylpyrazole) and C4, [PdCl2(L4)] (L4 = 3-phenyl-1H-pyrazole) have been successfully synthesized. The ligands as well as the complexes were characterized by 1H NMR, IR, UV-vis, thermogravimetric analysis (TGA), cyclic voltammetry, magnetic measurements and mass spectrommetry. The antibacterial and antifungal activities of the ligands and the respective complexes were carried out using the Agar disk diffusion method on two gram positive bacteria (Staphylococcus aureus, Bacillus subtilis), two gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa) and one fungal, Candida albicans. All the compounds displayed biological activity to some extent. However, L3 was more active than most of other compounds towards all the microorganisms screened. The activity was found to generally improve after coordination to palladium metal especially for ligands which do not contain a ferrocenyl moiety.