New Copper Complexes with Antibacterial and Cytotoxic Activity

Abstract

The discovery of a new non-toxic metal complex with biological activity represents a very active area of research. Two Cu+2 complexes, [Cu4(L1)4(OH)4(DMF)2(H2O)] (C1) (HL1 = N-(5-ethyl-[1,3,4]–thiadiazole–2-yl)-benzenesulfonamide) and [Cu(L2)2(phen)(H2O)] (C2) (HL2 = N-(5-(4-methylphenyl)-[1,3,4]–thiadiazole–2-yl)-naphtalenesulfonamide), with two new ligands were synthesized. The X-ray crystal structures of the complexes were determined. In both complexes, Cu+2 is five-coordinated, forming a CuN2O3 and CuN4O chromophore, respectively. The ligands act as monodentate, coordinating the metal ion through a single Nthiadiazole atom; for the two complexes, the molecules from the reaction medium (phenantroline, dimethylformamide and water) are also involved in the coordination of Cu+2. The complexes have a distorted square pyramidal square-planar geometry. The compounds were characterized by FT-IR and UV-Vis spectroscopy. Using the microdilution method, the antibacterial activity of the complexes was determined against four Gram-positive and two Gram-negative bacteria, with Gentamicin as the positive control. Cytotoxicity studies were carried out on two tumor cell lines (HeLa, DLD-1) and on a normal cell line (HFL1) using the MTT method and Cisplatin as a positive control. Flow cytometric assessment of apoptosis induced by the complexes on the three cell lines was also performed. Both complexes present in vitro biological activities but complex C2 is more active.

A polymeric copper complex based on a pyrazole derivative: Synthesis, spectroscopic, X‐ray, and biological activity studies

“…The existence of phenyl and pyrazole groups within the pyrazole‐based ligand (Figure 1) is critical for evaluating the antitumor activities and the ability to interact with DNA. The aromatic structures within the ligand allow the complex to be close and interact with base pairs of the DNA via π‐stacking bonding 6 . Further studies are required to investigate the mode of action.…”

“…Tumor cells exhibit reduced vascularity causing a low level of O 2 , leading to the anaerobic process called the Warburg effect. The absence of O 2 within the cancer cell could allow the reduction of copper from the divalent to monovalent state giving an opportunity to copper compounds to target tumor cells 6 …”

Novel Sulfone 2-Aminobenzimidazole Derivatives and Their Coordination Compounds: Contribution of the Ethyl and Phenyl Substituents on Non-Covalent Molecular Interactions; Biological Antiproliferative Activity

“…Anal. calculated for ZnC 30 A solution of the ligand (0.1267 g, 0.5 mmol) and ZnCl 2 (0.0341 g, 0.25 mmol) in 15 mL of ethanol was stirred under reflux for 30 min. The reaction mixture was left to stand at room temperature.…”

“…In the presence of a reducing agent, these compounds induce DNA damage by ROS generation. Cytotoxicity studies with different cancer cell lines revealed that complexes [Cu(tnz) 2 (µ-Cl)Cl] 2 and [Cu(tnz) 2 Br 2 ] showed the highest cytotoxicity, while being moderately toxic to normal cells [26,27] Generally, the reported cytotoxic transition metal compounds have been synthesized using chelating ligands [28][29][30][31][32][33][34]. The results with non-chelating ligands, tinidazole and clotrimazole [35][36][37][38][39][40][41][42], have shown that weak interactions, such as hydrogen bonding, electrostatic interactions, π stacking, lp•••π or hydrophobic contacts, as well as geometry and redox properties, have an important role in the biological activity of coordination compounds with monocoordinated ligands.…”

Effect of Terminal Substituents of 2-Aminobenzimidazoles on Non-Covalent Molecular Interactions in Their Transition Metal Coordination Compounds. Evaluation of Their Biological Activity

“…In the presence of a reducing agent, these compounds induce DNA damage by ROS generation. Cytotoxicity studies with different cancer cell lines revealed that complexes [Cu(tnz) 2 (µ-Cl)Cl] 2 and [Cu(tnz) 2 Br 2 ] showed the highest cytotoxicity, while being moderately toxic to normal cells [26,27] Generally, the reported cytotoxic transition metal compounds have been synthesized using chelating ligands [28][29][30][31][32][33][34]. The results with non-chelating ligands, tinidazole and clotrimazole [35][36][37][38][39][40][41][42], have shown that weak interactions, such as hydrogen bonding, electrostatic interactions, π stacking, lp•••π or hydrophobic contacts, as well as geometry and redox properties, have an important role in the biological activity of coordination compounds with monocoordinated ligands.…”