Spectral, thermal and antimicrobial properties of novel mixed ligand-metal complexes derived from saccharinate complexes and azo dye ligand

Background and Objective: Saccharin and saccharinate (sac) complexes and its anion have critical importance with biological, biochemical and pharmacological properties. The main objective of this study was to synthesize the novel mixed ligand complexes from the complexes [M(Sac)2(H2O)4]·2H2O [M: Mn(II), Co(II), Ni(II), Cu(II) and Cd(II)] with a second neutral ligand [L:(mmppa): 5-Methyl-4-(4-methylphenylazo)-2H-pyrazole-3-ylamine]. Methodology: The structures of the complexes were characterized by elemental analysis, magnetic susceptibility, FT-IR, mass and electronic spectral studies and thermal analysis. Antimicrobial (antibacterial and anticandidal) activities of the complexes were tested against Enterococcus faecalis ATCC 51299, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 35218, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 700603 and Candida albicans ATCC 64548. Results: According to the experimental results, it was determined that in Mn(II), Co(II) and Cd(II) complexes, two coordinated H2O molecules are replaced with two neutral ligands, on the other hand, in Ni(II) and Cu(II) complexes, all coordinated H2O molecules are replaced with four neutral ligands. It was established that the second neutral ligand was coordinated to the metal ions via nitrogen atom of-NH2 group in pyrazole ring. In antimicrobial activity, study was determined to occur significant inhibition zones (20-24 mm) against Candida albicans ATCC 64548 strain. Conclusion: As a result, mononuclear and monomeric structure in octahedral geometry including both saccharin and azo dye ligands were synthesized and their characterizations were accomplished. The result of this study shows that novel mixed ligand-saccharinate complexes can be utilized for the development of anticandidal agents.