Syntheses, structural and thermal studies on Zn(II) complexes of 5-aryl-1,3,4-oxadiazole-2-thione and dithiocarbamates: Antibacterial activity and DFT calculations

Antiproliferative activity and electrochemical oxygen evolution by Ni(II) complexes of N'-(aroyl)-hydrazine carbodithioates

The electrochemical water splitting by transition metal complexes is emerging very rapidly. The nickel complexes also play a very vital role in various biological activities. Here, three new ligands {H₂mbhce = N'-(4-methyl-benzoyl), H₂pchce = N'-(pyridine-carbonyl) and H₂hbhce = N'-(2-hydroxy-benzoyl) hydrazine carbodithioic acid ethyl ester} and their corresponding Ni(II) complexes [Ni(Hmbhce)₂(py)₂] (1), [Ni(pchce)(o-phen)₂]·CH₃OH·H₂O (2) and [Ni(hbhce)(o-phen)₂]·1.75CHCl₃·H₂O (3) have been synthesized and fully characterized by various physicochemical and X-ray crystallography techniques. The photoluminescence study and thermal degradations were also examined. The treatment of K562 cells with the increasing concentrations of the nickel salts, ligands, and complexes 1, 2, and 3 showed dose-dependent cytotoxicity. The cytotoxic activity of ligands reveals that ligand H₂mbhce is more potent in inhibiting the growth of tumor cells in comparison to other ligands H₂pbhce and H₂hbhce. Cytotoxicity assay results indicate that all complexes have remarkable cytotoxic potential in comparison to either nickel salts or the free ligands. Among these complexes, complex 1 has significantly better anti-tumor activity as compared to complexes 2 and 3. The electrochemical study of complexes 1, 2, and 3 for water oxidation reveals that all the complexes possess admirable electrocatalytic activity towards oxygen evolution reaction (OER) and have lower overpotential (328, 338, and 370 mV, respectively) than many previously reported complexes and RuO₂ (390 mV). Among complexes 1, 2, and 3, complex-2 shows a better water oxidation response. Consequently, these complexes have great potential to be utilized in fuel cells. The more reliable electrochemical parameter TOF is also calculated for all three complexes.

Insights into the Antimicrobial Potential of Dithiocarbamate Anions and Metal-Based Species

Bacterial infection remains a worldwide problem that requires urgent addressing. Overuse and poor disposal of antibacterial agents abet the emergence of bacterial resistance mechanisms. There is a clear need for new approaches for the development of antibacterial therapeutics. Herein, the antibacterial potential of molecules based on dithiocarbamate anions, of general formula R(R’)NCS2(−), and metal salts of transition metals and main group elements, is summarized. Preclinical studies show a broad range of antibacterial potential, and these investigations are supported by appraisals of possible biological targets and mechanisms of action to guide chemical syntheses. This bibliographic review of the literature points to the exciting potential of dithiocarbamate-based therapeutics in the crucial battle against bacteria. Additionally, included in this overview, for the sake of completeness, is mention of the far fewer studies on the antifungal potential of dithiocarbamates and even less work conducted on antiparasitic behavior.

A Novel ZnII Complex Bearing Two Monodentate (4-Methoxyphenyl)[(1E, 2E)-3-phenylprop-2-en-1-ilidene] Schiff Bases: Crystal Structure and DFT Study

A novel ZnII complex bearing two monodentate (4-methoxyphenyl)[(1E, 2E)-3-phenylprop-2-en-1-ilidene] Schiff bases was synthesized and investigated both in the solid state by single-crystal X-ray diffraction, elemental analysis, and FTIR and in solution by 1H NMR spectroscopy. The complex crystallizes in the P21/c monoclinic space group. The asymmetric unit contains one ZnII ion coordinated to two Schiff base ligands and two chloride ions, in a distorted tetrahedral geometry. The title complex was also investigated by DFT, using the hybrid functional B3LYP with basis set 6-31G++, which reproduced the geometry and structural features of the complex in the crystal, and was used to assign the main bands in the FTIR spectrum. In solution, the complex maintains its integrity against decomposition to the parent reagents.

Square planar Ni(ii) complexes of acetoneN4-phenyl-thiosemicarbazone andin situgenerated benzoyl thiosemicarbazide ligands: synthesis, spectral and structural characterizations, thermal behaviour and electrochemical studies

Two novel complexes [Ni(Hapt)₂] (1) and [Ni(btsc)] (2) have been synthesized from Hapt and Hbtsc by the reaction of Ni(ii) salt.

5-(2-Methylfuran-3-yl)-N-phenyl-1,3,4-oxadiazol-2-amine

In the title compound, C13H11N3O2, the furan ring is disordered over two orientations, with occupancies of 0.902 (2) and 0.098 (2). The dihedral angles between the central oxadiazole ring and the pendant phenyl ring and the furan ring (major disorder component) are 10.12 (11) and 1.76 (15)°, respectively. A short intramolecular C—H...O contact generates anS(6) ring. In the crystal, inversion dimers linked by pairs of N—H...N hydrogen bonds generateR22(8) loops. The dimers are linked by C—H...π and π–π interactions [range of centroid–centroid distances = 3.301 (7)–3.689 (1) Å], generating a three-dimensional network.

Ag(i), Cu(ii), Co(iii) and Hg(ii) complexes and metal-assisted products derived from 4-methyl-piperidine-carbodithioate: syntheses, structures, thermal analyses, redox behaviour and fluorescence properties

Ag(i), Cu(ii), Co(iii) and Hg(ii) complexes and metal-assisted products derived from 4-methyl piperidine have been synthesized. The Cu(ii) complex is redox reversible and compounds3and5are fluorescent.