The formation of a metallosupramolecular porous helicate through salicylaldehydethiosemicarbazone: Synthesis, Characterization, Cytotoxic activity, DNA binding and DFT calculations

• Published in: Applied organometallic chemistry 2019-09, Vol.33 (9), p.n/a
• Main Authors: Avcu Altiparmak, Elif, Ozen Eroglu, Guneş, Ozcelik, Elif, Özdemir, Namık, Erdem Kuruca, Serap, Arsu, Nergis, Ülküseven, Bahri, Bal‐Demirci, Tulay
• Format: Article
• Language: English
• Subjects: Binding; Chemistry; Crystal lattices; Crystal structure; Cytotoxicity; Density functional theory; DFT; DNA binding; Ethylenediamine; Helicate; Infrared analysis; Infrared spectroscopy; Iron; Leukemia; Ligands; Low concentrations; Magnetic moments; Mathematical analysis; Metal ions; supramolecular; Toxicity testing
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.5023

The reaction of salicylaldehyde‐S‐methylisothiosemicarbazone in the presence of ethylenediamine base and iron (III)chloride generated unforeseen homotopic dinuclear triple‐stranded iron (III)helicate. The synthesized helicate was characterized by elemental analysis, IR, UV–Vis spectroscopy, magnetic moment measurement, and evaluated cytotoxic activities against K562, HL‐60 and THP‐1 leukemia cells. In addition, solid‐state structure has been determined by single‐crystal X‐ray diffraction technique. In the complex, three dinucleating O, N, N, O donor ligands provide three diazine (═N─N═) bridges between the metal ions and facial O3N3 coordination spheres around them. The ligands are folded about the N─N single bond and coordinated to the two metal ions in a helical fashion to form the triple helical structure. In the crystal lattice, chains of centrosymmetric R2212 rings, which are connected to one another via π─π stacking interactions, are generated by C─H···O intermolecular interactions. The results are also confirmed by the density functional theory (DFT) calculations. The results obtained from the cytotoxicity test showed to be effective in low concentrations on the leukemia cells. An intercalative binding mode of helicate‐DNA complex was confirmed with the high intrinsic binding constant (Kb = 8×106 M−1) and competitive displacement assay of Ethidium bromide with high Ksv value. Supramolecular dinuclear triple‐stranded iron (III)helicate was characterized by spectroscopic methods, and its crystal structure was determined by X‐ray crystallography. The results were confirmed by the density functional theory calculations. The results obtained from the cytotoxicity test showed to be effective in low concentrations on the leukaemia cells. An intercalative binding mode of helicate‐DNA complex was confirmed with the high intrinsic binding constant (Kb = 8×106 M−1) and competitive displacement assay of ethidium bromide with high Ksv value.