Synthesis, Structure, and Magnetic and Biological Properties of Copper(II) Complexes with 1,3,4-Thiadiazole Derivatives

Abstract

New coordination compounds of copper(II) with 2,5-bis(ethylthio)-1,3,4-thiadiazole (L1) and 2,5-bis(pyridylmethylthio)-1,3,4-thiadiazole (L2) with compositions Cu(L1)2Br2, Cu(L1)(C2N3)2, Cu(L2)Cl2, and Cu(L2)Br2 were prepared. The complexes were identified and studied by CHN analysis, infrared (IR) spectroscopy, powder X-Ray diffraction (XRD), and static magnetic susceptibility. The crystal structures of Cu(II) complexes with L1 were determined. The structures of the coordination core of complexes Cu(L2)Cl2 and Cu(L2)Br2 were determined by Extended X-ray absorption fine structure (EXAFS) spectroscopy. Magnetization measurements have revealed various magnetic states in the studied complexes, ranging from an almost ideal paramagnet in Cu(L1)2Br2 to alternating-exchange antiferromagnetic chains in Cu(L1)(C2N3)2, where double dicyanamide bridges provide an unusually strong exchange interaction (J1/kB ≈ −23.5 K; J2/kB ≈ −20.2 K) between Cu(II) ions. The cytotoxic activity of copper(II) complexes with L2 was estimated on the human cell lines of breast adenocarcinoma (MCF-7) and hepatocellular carcinoma (HepG2).

Synthesis, crystal structure and Hirshfeld surface analysis of bromidotetrakis[5-(prop-2-en-1-ylsulfanyl)-1,3,4-thiadiazol-2-amine-κN 3]copper(II) bromide

“…Nitrogen-containing heterocycles are a promising class of ligands for the synthesis of transition-metal complexes that are strongly responsive to the changes in external conditions (Lavrenova et al, 2023). Derivatives of 1,3,4-thiadiazole represent a relatively new class of compounds that demonstrate a broad array of biological activities, making them of significant interest to various fields in medicinal chemistry and pharmacology worldwide (Gowramma et al, 2018;Kaviarasan et al, 2020;Upadhyay & Mishra, 2017;Yusuf et al, 2008).…”

Cooperativity of ESPT and Aggregation-Induced Emission Effects—An Experimental and Theoretical Analysis of a 1,3,4-Thiadiazole Derivative

“…Numerous 1,3,4-thiadiazole-based molecules have also been considered in the process of designing novel lasers [ 8 ], oxidation inhibitors [ 9 ], and chelating agents for complexation of various d-block metal ions [ 10 ]. In recent years, many research teams, ours included, have been engaged in studies of 1,3,4-thiadiazole derivatives demonstrating a variety of interesting crystallographic, spectroscopic and biophysical properties [ 11 ], often considered as essential for pharmacological potential. Some of the identified spectroscopic effects include changes in spectral characteristics in complexes with transition metal ions [ 12 ], dynamics changes in lipid systems [ 13 , 14 ], or the emergence of dual fluorescence.…”