Iron(III) complexes based on tetradentate thiosemicarbazones: Synthesis, characterization, radical scavenging activity andin vitrocytotoxicity on K562, P3HR1 and JURKAT cells

Abstract

Nine iron(III) complexes, [Fe(L)Cl], were synthesized starting from S-alkylthiosemicarbazones and some substituted aldehydes. The L ligands formed by template condensation are N 2 O 2-chelating structures and named N 1acetylacetone-N 4-R-salicylidene-S-alkyl-thiosemicarbazidato (L 2−) where alkyl = methyl, propyl, or allyl and R = 3-methoxy, 4-methoxy, or 3,5-dichloro. The complexes were characterized using elemental analysis, IR, and ESI-MS. X-ray diffraction analysis of complex Fe8 (as a representative sample) indicated a square pyramid environment of the iron ion. The cytotoxicity performances of the complexes were determined using chronic myelogenous leukemia (K562), Burkitt's lymphoma (P3HR1), and T-cell leukemia (JURKAT) cell lines. For comparison, the noncancerous cell lines, human umbilical vein endothelial (HUVEC) and diploid fibroblast (3T3), and imatinib as positive control were included in the study. MTT results revealed that complexes Fe2, Fe5, Fe7, and Fe8 with methoxy (OCH 3) substituent have remarkable cytotoxic effects on K562 and P3HR1 cells at relatively low concentrations in the ranges of 4.81-14.05 and 5.61-11.98 μM, respectively. The radical scavenging activities of the complexes were measured for DPPH, superoxide anion (O 2 •−), hydroxyl (•OH) radicals, and hydrogen peroxide (H 2 O 2). Complexes Fe2, Fe3, Fe5, and Fe8, which exhibited selective cytotoxicity, were able to compete also with vitamin E in terms of ROS scavenging activities.

New mixed‐ligand iron(III) complexes containing thiocarbohydrazones: Preparation, characterization, and chemical reactivity analysis through theoretical calculations

“…The electronic spectra of the complexes did not give any evidence related to square pyramidal geometry, possibly due to the low intensity of d-d transitions. [25,57,58]…”

“…The design, synthesis, and characterization of iron complexes are important in many fields as they provide synthetic models for iron-containing enzymes. [23][24][25] Mixed ligand Schiff base complexes have wide applications such as photoluminescence, catalysis, and material fabrication. [26][27][28] Especially iron complexes emerge as up-and-coming catalysts as a result of the relatively low toxicity and price of iron.…”

“…The design, synthesis, and characterization of iron complexes are important in many fields as they provide synthetic models for iron‐containing enzymes. [ 23–25 ]…”

In vitro biological and in silico screening of novel iron(iii) complexes for DNA-targeted antitumor drug component

“…31 A series of iron( iii )-thiosemicarbazone complexes have selective cytotoxic effects against K562 and P3HR1 cells at relatively low concentrations and they can also compete with vitamin E in terms of their ROS scavenging activity. 32…”

“…31 A series of iron(III)-thiosemicarbazone complexes have selective cytotoxic effects against K562 and P3HR1 cells at relatively low concentrations and they can also compete with vitamin E in terms of their ROS scavenging activity. 32 Therefore, we report here the synthesis and structural analysis of new thiosemicarbazone-based iron(III) complexes and in vitro biological screening of their DNA binding and cleavage, topoisomerase-IIa and XO inhibitor, antitumor and antioxidant activities. In addition, we present the various predicted pharmacokinetic properties of the iron(III) complexes in accordance with in vitro biological studies, and therefore the drug-like nature of these complexes with in silico screening studies.…”