Iron(II) complexes containing the 2,6-bis-iminopyridyl moiety. Synthesis, characterization, reactivity, and DNA binding

Abstract

Two iron(II) complexes, [Fe II (py t BuN 3 ) 2 ](FeCl 4 ) (1) and [Fe II (py t BuMe 2 N 3 )Cl 2 ] (2), with sterically constrained py t BuN 3 and py t BuMe 2 N 3 chelate ligands (py t BuN 3 = 2,6-bis-(aldiimino)pyridyl; py t BuMe 2 N 3 = 2,6-bis-(ketimino)pyridyl), have been synthesized and characterized by elemental analysis, IR, UV-vis spectra and preliminary X-ray single-crystal diffraction. The latter revealed that Fe(II) in 1 is six-coordinate by six nitrogen donors from two bisiminopyridines in a distorted octahedron. Complex 2 reacts with thiourea with a second-order rate constant k 2 = (2.50 ± 0.05) × 10 -3 M -1 s -1 at 296 K, and the reaction seemed to be slow. In a similar way, the interaction of 2 and DNA was studied by fluorescence and absorption spectroscopy. The results revealed that 2 caused fluorescence quenching of DNA through a dynamic quenching procedure. The binding constants K A , K app and K SV as well as the number of binding sites between 2 and DNA were determined.

Norfloxacin La(III)-based complex: synthesis, characterization, and DNA-binding studies

“…The effect of Mg 2+ ion, which is a required cofactor for the enzymatic process, on norfloxacin-scDNA binding was also investigated. As an extension of a previous study in this area [8], we report herein the synthesis of a lanthanum complex with norfloxacin. The aim for using lanthanum was because rare earth metals have been widely used for their coordination properties and special chemical characteristics arising from 4f electrons and the properties to form isostructural complexes [9].…”

BSA Interaction, Molecular Docking, and Antibacterial Activity of Zinc(II) Complexes Containing the Sterically Demanding Biomimetic N3S2 Ligand: The Effect of Structure Flexibility

“…As part of our focus on bioactive materials research [ 18 , 19 , 20 , 21 , 22 ], we report here on the binding of BSA to DBZ and DBZH 4 complexes using various techniques, e.g., UV–vis absorption and fluorescence, time-correlated single-photon counting, and cyclic voltammetry. The association constants, binding sites, and forces between the two complexes and BSA are reported, discussed, and correlated with the structure.…”