Silver(I) pyridinyl complexes with benzothiazole, thiophene, and furan moieties: DNA/protein‐binding, antibacterial, antioxidant, and anticancer studies

Abstract

We have synthesized and characterized nine Ag(I) complexes of Schiff bases containing thiophene, furan, and pyridine moieties for in vitro antibacterial, antioxidant, anticancer activities, and DNA/bovine serum albumin (BSA) binding studies. Based on the analytical and spectral analyses, a linear geometry was proposed for all the Ag(I) complexes, except for one (with the furan moiety), which formed a distorted T‐shaped geometry. UV‐vis absorption studies on the interactions of calf thymus‐DNA (CT‐DNA) with the nine Ag(I) complexes pointed to an intercalative binding mode. With a binding constant Kb of 3.75 × 105 M−1, the complex bearing a benzothiazole moiety (1) interacted stronger with CT‐DNA than the rest of the complexes. Fluorescence spectroscopic data revealed that the complexes had a modest binding affinity for BSA through static quenching. The complexes displayed good antioxidant properties, especially those with a benzothiazole moiety. Notable antibacterial activities against methicillin‐resistant Staphylococcus aureus, Staphylococcus aureus, Salmonella typhimurium, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae were observed for complexes with the furan and thiophene moieties. The in vitro anticancer studies of selected complexes against three cancer cell lines showed that the complexes were more effective against the inhibition of the growth of cervical cancer cells relative to cisplatin.

Spectroscopic investigation and structural simulation in human serum albumin with hydroxychloroquine/Silybum marianum and a possible potential COVID‐19 drug candidate

“…To identify the preferred binding site of the HCQ/SM mixture on HSA, the binding constant for the interaction between the HCQ/SM compound and HSA was frequently determined using modified Stern-Volmer plots, represented by log [Q] versus log [(F 0 − F)/F]], as shown in Figure 5b of Equation ( 2). [33][34][35]38] The binding between drugs and HSA was found to suggesting that HSA possesses a single binding site for the interaction with the HCQ/SM mixture. [1,36,39,40] The slope of the plot allows for the evaluation of K LB and f a .…”

“…In this case, the interaction between the HCQ/SM mixture and HSA results in a static quenching process. [38] …”

Mononuclear discrete Ag(I) complexes of aryl substituted (E)-N-phenyl-1-(pyridin-3-yl)methanimine: In vitro biological activities and interactions with biomolecules

“…The intercept-to-slope ratio of 1/[A − A°] vs 1/[complex] linear curve was used to compute the binding constant K b where A and A° denote BSA absorbance in the presence and absence of complexes, respectively. 43,44 For the fluorescence quenching assay, a 1 µM BSA solution was titrated against various concentrations of the complexes (0-35 µM) and incubated at 25 °C for 8 mins. The wavelength of BSA was excited at 280 nm and emitted at 346 nm.…”

Synthesis and Therapeutic Potential of selected Schiff Bases: In vitro Antibacterial, Antioxidant, Antidiabetic, and Computational Studies

“…This is not far from their ability to combat Gram‐positive and Gram‐negative bacteria, including drug‐resistant ones. Their ability to target and inhibit the growth of pathogenic bacteria also makes them invaluable in developing new antibacterial agents [5,6] . As the search for new and more effective antibacterial treatments continues, Schiff bases are still a promising avenue for research and drug discovery.…”