Synthesis, characterization and medical efficacy (hepatoprotective and antioxidative) of albendazole-based copper(II) complexes – an experimental and theoretical approach

Spectrophotometric determination of Zr(IV), Hg(II) and U(VI) in solution with their analytical applications: Structural characterization and molecular docking of the solid complexes

Spectrophotometry was used to determine trace amounts of Zirconium(IV), Mercury(II) and Uranium(VI) in environmental, biological, pharmaceutical and industrial samples. The determination depend on the complexation reactions between albendazole reagent and metal ions [Zr(IV), Hg(II) and U(VI)] at 555 nm, 485 nm and 510 nm, respectively. The experimental conditions were explored to reach the optimum conditions for albendazole-metal ions interaction, including detection of a suitable wavelength, medium (pH), reagent concentration, surfactants effect, reaction time and temperature. Under optimum conditions, the complexes displayed apparent molar absorptivities of 0.8350 × 10⁴, 0.6210 × 10⁴ and 0.7012 × 10⁴ L mol^-1 cm^-1; Sandell's sensitivity of 0.01092, 0.03230 and 0.03394 µg cm^-2 and with linearity ranges of 1.0-120.0, 3.0-200.0 and 1.0-150.0 µg mL^-1 for the developed methods, respectively. Furthermore, Elemental analysis, thermal analysis (TGA, DTG), IR, ¹HNMR, spectroscopies, electrical molar conductivity and magnetic moment measurements were used to determine the structures and characteristics of the complexes. A careful examination of the IR spectra revealed that the ligand interacted with all of the metal ions described as a bidentate via the oxygen of the carbonyl of the ester moiety and the nitrogen atom of the heterocyclic CN group. An octahedral geometry for Zr(IV), Hg(II) and U(VI) complexes has been postulated based on magnetic and electronic spectrum data. The band gap values indicated that these complexes were semi-conductors and belong to the same class of extremely effective solar materials. The albendazole ligand and its complexes have been biologically tested against a variety of bacterial and fungal strains, and molecular docking studies have been conducted to evaluate the optimal binding site and its inhibitory action.

Practical and Computational Studies of Bivalence Metal Complexes of Sulfaclozine and Biological Studies

In the search for novel, metal-based drug complexes that may be of value as anticancer agents, five new transition metal complexes of sulfaclozine (SCZ) with Cu(II), Co(II), Ni(II), Zn(II), and Fe(II) were successfully synthesized. The chemical structure of each complex was characterized using elemental analysis (CHN), IR spectroscopy, UV–Vis spectroscopy, thermogravimetric analysis (TGA), and electronic paramagnetic resonance (EPR) spectroscopy. IR spectra indicated that the donor atoms were one sulfonyl oxygen atom and one pyrazine nitrogen atom, which associated with the metal ions to form a stable hexagonal coordination ring. The metal–ligand stability constant (K_f) revealed that Cu(II) and Ni(II) have good coordination stability among the metal compounds. Theoretical studies using DFT/B3LYP were performed to further validate the proposed structures. The obtained results indicated that Cu(II) has a trigonal bipyramidal geometry, whereas Fe(II), Co(II), and Ni(II) have an octahedral structure, while Zn(II) has a tetrahedral arrangement. The bio-activities of the characterized complexes were evaluated using DNA binding titration and molecular docking. The binding constant values for the metal complexes were promising, with a maximum value for the copper metal ion complex, which was 9 × 10⁵ M^-1. Molecular docking simulations were also carried out to evaluate the interaction strength and properties of the synthesized metal complexes with both DNA and selected cancer-relevant proteins. These results were supported by in vitro cytotoxicity assays showing that the Cu(II) and Ni(II) complexes display promising antitumor activity against colon and breast cancer cell lines.

Coordination compounds with heterocyclic ester derivatives. Structural characterization and anti-proliferative activity

A series of new coordination compounds of cobalt(II), copper(II) and zinc(II) with heterocyclic ester derivatives (ethyl 4-methyl-5-imidazole-carboxylate (emizco), 1-(2-(phenylsulphonyl)ethyl)-4-imidazole carboxylate (semizco)) and methyl 5-(propylthio)-2-benzimidazolecarbamate (albendazole, abz) were synthesized. They were fully characterized by different techniques such as IR, UV-Vis-NIR, elemental analysis, molar conductivity and magnetic susceptibility. Additionally, X-ray crystal structures of semizco and its [Co(semizco)₂Cl₂]·2CH₃CN 10, [Co(smmizco)₂Br₂]·2CH₃CN 11 and [Cu(semizco)₂Br₂] 15 coordination compounds are analyzed. These compounds present lone pair SO⋯π interactions between the sulfone and the imidazolic ring. These ligands showed three coordination modes: monodentate, through an imidazolic nitrogen atom, or a bidentate chelating mode by a nitrogen and an oxygen atom from the ester group. The different coordination modes and the number of coordinated ligands gave rise to tetrahedral and octahedral compounds, or for [Cu(semizco)(μ-Br)Br]_n·0.5H₂O 7 a square base pyramidal geometry. A cytotoxic study was carried out with the free ligands and their copper(II) and zinc(II) halide coordination compounds on HeLa (cervix-uterine), MCF-7 (breast), HCT-15 (colon), PC3 (prostate) human carcinoma cell lines and L929 mouse fibroblast (healthy cells). A TUNEL assay (terminal deoxynucleotidyl transferase dUTP nick end labeling) was performed with the most active copper(II) compounds to determine if cell death was by apoptosis.

Synthesis and theoretical calculations of metal-antibiotic chelation with thiamphenicol: in vitro DNA and HSA binding, molecular docking, and cytotoxicity studies

New metal complexes showed the magic of the bivalent metal which have higher bioactivity than free ligand.

Nanoformulations of albendazole as effective anticancer and antiparasite agents

Initially emerging as a widely used clinical antiparasitic drug, albendazole (ABZ) has been increasingly recognized as an effective anticancer agent due to its outstanding advantage, in other words, low toxicity to normal cells but high effectiveness against parasites and some tumors. The major challenge is its poor water solubility and subsequently low bioavailability. This article thus first reviews the brief achievements in using ABZ to treat parasites and cancers, and summarizes the basic mechanisms of action of ABZ. Then this article critically reviews recent nanotechnological strategies, in other words, formulating/conjugating it with carriers into nanoformulations, in practices of improving aqueous solubility and efficacy in treatment of tumors and parasites. Our expert opinions in this field are provided for more effective delivery of ABZ to treat tumors and parasites in vivo.