Synthesis, spectral characterization, crystal structure and antibacterial activity of nickel(II), copper(II) and zinc(II) complexes containing ONNO donor Schiff base ligands

Novel Zinc(II) and Copper(II) Complexes of 2-((2-Hydroxyethyl)amino)quinoline-3-carbaldehyde for Antibacterial and Antioxidant Activities: A Combined Experimental, DFT, and Docking Studies

“…Moreover, a very weak vibrational band was observed at 598 cm –1 for ν(Zn–O) and a medium band at 529 cm –1 for ν(Zn–N) bonds of the zinc complex and medium bands at 607 and 544 cm –1 for ν(Cu–O and Cu–N) bonds of the copper complex, in line with literature data. 2 , 15 , 24 , 70 , 71 This indicates that both Zn(II) and Cu(II) metals were bonded to the donor atoms of the ligand during the complexation process.…”

“… 1 Therefore, there are reports of extensive drug discovery studies being carried out elsewhere to develop new therapeutic approaches and effective drugs with a wide range of antimicrobial activities toward biological targets. 2 − 4 In this aspect, quinoline is among the most important nitrogen-containing heterocyclic molecules being used for the synthesis of biologically active molecules. 5 , 6 It plays a vital role in biochemical processes as a pharmaceutical agent with its skeleton being often used for the design of many synthetic compounds having diverse pharmacological properties.…”

“…Microbial drug resistance has become a serious medical problem, causing morbidity and mortality, which has attracted the attention of different researchers working on the discovery of antimicrobial drugs . Therefore, there are reports of extensive drug discovery studies being carried out elsewhere to develop new therapeutic approaches and effective drugs with a wide range of antimicrobial activities toward biological targets. − In this aspect, quinoline is among the most important nitrogen-containing heterocyclic molecules being used for the synthesis of biologically active molecules. , It plays a vital role in biochemical processes as a pharmaceutical agent with its skeleton being often used for the design of many synthetic compounds having diverse pharmacological properties. − Quinoline derivatives are also being used for antiprotozoal, antifungal, anticancer, antiviral, antioxidant, and antibacterial ,, activities.…”

“…Several coordination compounds of metal ions (chromium, cobalt, copper, manganese, molybdenum, palladium, ruthenium, tungsten, vanadium, and zinc) have been applied in the treatment of various diseases owing to their antimicrobial and antioxidant, − anticancer, , antiproliferative, , anti-inflammatory, DNA binding and cytotoxicity, ,,, antitumor, and antidiabetic activities. Studies also indicated that Zn­(II) complexes exhibit anti-inflammatory, antidiabetic, antioxidant, and antimicrobial activities, , whereas Cu­(II) complexes exhibited promising antimicrobial, antioxidant, antiviral, DNA binding, ,, and antiproliferative activities. Previous studies of a zinc­(II) complex of quinoline derivative ligand indicated an in vitro biological screening effect tested against four bacterial strains, Escherichia coli and Pseudomonas aeruginosa (Gram-negative) as well as Staphylococcus aureus and Bacillus subtilis (Gram-positive).…”

Role of hydrazone substituents in determining the nuclearity and antibacterial activity of Zn(ii) complexes with pyrazolone-based hydrazones

“…Significantly, a different behaviour was observed towards E. coli , since 99.9% inhibition of bacterial growth was observed only by complex 5 after 8 hours, which was maintained even 24 hours after treatment, showing both bacteriostatic and bactericidal activity. Generally, other Schiff base complexes reported in the literature 57–59 display an enhanced bactericidal effect than the free ligands, according to the Overtone's concept 60 and the chelation theory. 61…”