Iron(III) Schiff base complexes with asymmetric tetradentate ligands: synthesis, spectroscopy, and antimicrobial properties

Abstract

The synthesis and characterization is reported of four iron(III) complexes of general formula [Fe(pythsalX)-(H 2 O) 2 ]Cl 2 , derived from the NSNO-donor tetradentate Schiff base ligands pythsalHX ([5-X-N-(2-pyridylethylsulfanylethyl)salicylideneimine] (X = OMe, N 2 Ph, I, NO 2 ). The complexes were characterized by physico-chemical and spectroscopic methods. The thermal stabilities of both the free Schiff bases and their complexes were studied by differential scanning calorimetry and thermogravimetric analyses. The spectroscopic data suggest that the Schiff base ligands coordinate through deprotonated phenolic oxygen, imine, and pyridine-type nitrogens and the thioether sulfur atoms to give an octahedral geometry around the iron(III) atom in all these complexes. The free Schiff bases and their complexes have been screened for antimicrobial activities and the results show that the free Schiff bases are more potent antibacterials than the complexes.

Synthesis, characterization, DNA binding/cleavage, and anticancer and antimicrobial activities: Nano‐sized Co(II) and Cd(II) complexes and their use as a precursor for CoO and CdO nanoparticles

“…Schiff base ligands and their metal chelates are included in a number of biological reactions, such as the inhibition of DNA and RNA; protein synthesis; nitrogen fixation; and carcinogenes. [11] The Schiff base chelates have received much attention because of their versatile use in many technical applications such as dyeing, [12] printing systems, [13,14] as well as in catalysis. [15][16][17][18] Schiff compounds are an important class of ligands that have attracted a great deal of interest because of their rich coordination chemistry.…”

Synthesis, characterization and catalytic activity of polymer anchored transition metal complexes toward oxidation reactions

“…Coordination of azomethene nitrogen in the complexes is suggested by the shift of m(C=N) azomethene to lower frequencies in the IR spectra of the complexes compared to the ligand [19]. Another band at 1,594 cm -1 in the free ligand is due to m(C=N) pyridine group and is also shifted toward lower frequency on complexation [20]. This indicates that the nitrogen atom of the pyridine group is also involved in complex formation.…”

Microwave-Assisted Synthesis, Crystal Structures, and In Vitro Antibacterial Studies of Manganese(III) and Iron(III) Complexes Derived From N,N′-1,2-ethylene-bis(3-ethoxysalicylideneimine)

“…Essential metal ions such as manganese and iron and their complexes are found to be antitumor active, catalytic active, antimicrobial and cytotoxic. [9][10][11][12] In this study, the synthesis, characterization and antibacterial properties of a mononuclear manganese(III) complex [MnL (dca)(OH 2 )] and a mononuclear iron(III) complex [FeLL ]· ClO 4 (H 2 L = N,N -1,2-ethylene-bis(3-ethoxysalicylideneimine); L' = 2-[(2-ammonioethylimino)methyl]-6-ethoxyphenolate; dca = dicyanamide), are described.…”