Spectroscopic Studies of Ag(I) Pyridinyl Ligands Complexes interaction with CT-DNA and their In Vitro Biological Studies
Five bidentate Pyridinyl Schiff bases and their Silver(I) complexes are reported in this study. The Silver(I) salts used are; AgNO3, AgClO4, AgCF3SO3. The pyridinyl Schiff base ligands; L1-5 were synthesized by refluxing an equimolar amount of 2-pyridine carboxaldehyde with 2-aminophenol, 2-aminothiophenol, 2-fluoroaniline, p-toluidine, and 2-thiophenemethylamine respectively. Two equivalent of the obtained ligands were reacted with one equivalent of silver(I) salts in anhydrous ethanol under constant stirring at room temperature forming complexes of general formula [AgL2]+X-. Elucidation of the complexes structure was done using 1H-NMR, 13C-NMR, Electrospray ionization mass spectrometry, Elemental analysis, Infrared spectroscopy, and some by Single-crystal X-ray diffraction analysis. The ligands coordinated via the azomethine nitrogen and pyridine nitrogen to the silver(I) ion in a distorted tetrahedral geometry having the counter anion outside the coordination sphere. The compounds were investigated for biological activities and binding affinities with calf thymus DNA (CT-DNA) and protein (Bovine serum albumin). An excellent in vitro antimicrobial and antioxidant activities were recorded for the complexes together with high binding affinity with CT-DNA and protein.
Keywords: Ag(I) complexes, Pyridinyl Schiff bases, Antimicrobial, Antioxidant, DNA binding, Protein binding.