Characterization, cyclic voltammetry and biological studies of divalent Co, Ni and Cu complexes of water-soluble, bioactive and photoactive thiosemicarbazone salt

Eugenol's electrochemical behavior, complexation interaction with copper chloride, antioxidant activity, and potential drug molecular docking application for Covid-19

Electrochemical studies were conducted to analyze the behavior of eugenol, CuCl2, and their complex using cyclic voltammetry. The oxidation mechanisms of eugenol and the redox behavior of copper ions were elucidated, showing differences in reversibility and charge transfer coefficients. Various kinetic and solvation parameters were determined. The redox behavior of CuCl2 was found to be more reversible compared to the copper-eugenol complex. The copper-eugenol complex exhibited enhanced antioxidant activity compared to eugenol and standard ascorbic acid. The eugenol was oxidized to form eugenol quinone methide through two postulated irreversible mechanisms. Molecular docking studies suggested higher potential bioactivity of the copper-eugenol complex towards the target protein of COVID-19 than the eugenol ligand.

1-D MOF [Ag2(C10H10N3O3S)2(C4H8N)2]n: photocatalytic treatment, crystallographic evaluation, ADMET parameters, CT-DNA and anticancer activity

Newly synthesized dinuclear crystalline polymer, the silver complex of bidentate Sulfamethoxazole (Ag-SMX) in the presence of secondary ligand pyrrolidine has been characterized by elemental, spectral (1H-NMR spectra, FT-IR spectra, UV-Vis spectra.), powder XRD, and single-crystal X-ray diffraction (single-crystal) analysis. The synthesis molecular structure of the dinuclear [Ag2(C10H10N3O3S)2(C4H8N)2]n complex reveals a one-dimensional polymeric chain with seesaw geometry (τ4 = 0.71): two silvers interlink each other by argentophilic interaction with Ag1…Ag2 separation distance of 3.0047(6) Å. The Hirshfeld surfaces (HS) and 2D fingerprint plots were used to examine the interconnects in the crystal packing. Molecule properties including MEP, MPA, HOMO-LUMO energy, and global reactivity descriptor parameters were computed to understand the molecule's stability. From ADMET parameters, human Intestinal Absorbance data revealed that the compound has the potential to be well absorbed, and also Ag-smx complex cannot cross the blood-brain barrier (BBB). The capacity of the silver complex to interact with CtDNA was investigated using absorption spectroscopy and viscosity tests. The interaction between CT-DNA reveals that the Ag-SMX complex exhibits the strongest binding affinity among all known sulfonamide derivatives and their metal complexes. The silver complex has higher inhibitory action than the free SMX ligand, according to data from a panel of gram (+ve) and gram (-ve) organisms' minimum inhibitory concentrations. In vitro cytotoxicity investigation revealed that the IC50 value for Ag-SMX is 57.12 g/mL and for SMX is 100.90 g/mL against human lung cancer cell line (A549). This study revealed that, when compared to SMX free-ligand, Ag-SMX is the most effective in terms of cytotoxicity toward the human lung cancer cell line (A549 cell line). In under 120 min, the synthesized Ag-smx complex showed exceptional photo-degradation characteristics against methylene blue (MB) (10 ppm) in visible light radiation.Communicated by Ramaswamy H. Sarma.

Spectroscopic, theoretical and computational investigations of novel benzo[b]thiophene based ligand and its M(II) complexes: As high portentous antimicrobial and antioxidant agents

The reaction of 3-chlorobenzo[b]thiophene-2-carbohydrazide with 4-(diethylamino) salicylaldehyde gave the new ligand; 3-chloro-N'-(4-(diethylamino)-2-hydroxybenzylidene)-benzo[b]thiophene-2-carbohydrazide. The Cu(II), Co(II), Ni(II), and Zn(II) complexes have been successfully prepared. The ligand and the complexes were characterized by analytical, FT-IR, 1H NMR, mass, UV-visible spectroscopy, molar conductivity, and magnetic susceptibility measurements. The FT-IR spectral data showed that the ligand adopted a tridentate fashion when binding with the metal ions via the nitrogen atoms of the imine (C = N), carboxyl (C = O), and phenolic oxygen (O-H) donor atoms. Density Functional Theory (DFT) estimations for the ligand at the DFT/B3LYP level via 6-31G++ (d, p) replicate the structure and geometry. Finally, HOMO and LUMO analyses were used for the charge transfer interface of the structure. Furthermore, molecular docking and ADME calculations were also performed to correlate and interpret the experimental results. The antimicrobial activity study illustrated enhancement in the activity of the free ligand upon complex formation, and the Cu(II) complex (MIC 25 µg mL-1) may be considered a promising antibacterial agent, and the Ni(II) and Zn(II) complexes (MIC 25 µg mL-1) as promising antifungal agents. Also, synthesized Cu(II) and Zn(II) metal complexes (MIC 3.125 µg mL-1) showed promising anti-TB activity against M. tuberculosis. Further, benzo[b]thiophene-based ligand and its metal complexes were evaluated for in vitro antioxidant activity, and in silico docking studies were carried out against Cytochrome c Peroxidase (PDB ID: 2X08).

Spectroscopic Characterization, Cyclic Voltammetry, Biological Investigations, MOE, and Gaussian Calculations of VO(II), Cu(II), and Cd(II) Heteroleptic Complexes

A novel hydrazone ligand (o-H₂BMP) N-(benzo[d]thiazol-2-yl)-3-oxo-3-(2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)propanamide alongside its Cu(II), Cd(II), and VO(II) complexes were prepared and structurally characterized via various spectroscopic analyses (Fourier transform infrared spectroscopy, UV-visible spectroscopy, ¹H/¹³C NMR spectroscopy, liquid chromatography coupled to mass spectrometry, and electron paramagnetic resonance spectroscopy) as well as by elemental analysis, thermal gravimetry analysis/differential thermal analysis, and magnetic moment measurements. Powder X-ray diffraction analysis was also performed for the free ligand and its metal complexes to determine the crystallographic structures and atomic spacing. It also provided information on unit cell dimensions and the average crystallite size. Furthermore, geometric optimization and computational studies were carried out by applying Gaussian (09) software based on density-functional theory coupled with the B3LYP functional and LANL2DZ/6-31+G(d,p) mixed basis set to evaluate some distinct features such as molecular electrostatic potential, E _HOMO, and E _LUMO. Moreover, electrochemical measurements were performed for Cu(II) in the absence/presence of the chelating agent to predict the effect of complexation interaction in the solution state study. As part of the biological examination, antioxidant and antimicrobial assays were conducted for each compound individually, in addition to cytotoxicity evaluations via MTT assays for all isolated complexes compared to the corresponding metal salts. The MOE (molecular operating environment) approach was also applied to model the interface between the isolated compounds and proteins that were expressed in breast cancer at the atomic level.

1,2,4-Triazine-based Materials: Spectroscopic Investigation, DFT, NBO, and TD-DFT Calculations as Well As Dye-sensitized Solar Cells Applications

In this manuscript, we report four series for 1,2,4-triazine derivatives as dye-sensitized solar cells (DSSCs). Density functional theory (DFT) methods via utilizing Becke's three-parameter functional and LeeeYangeParr functional (B3LYP) level with 6-31G (d, p) basis set to investigate their modeling molecular structures. Optimized molecular structures for studied molecular structures are obtained using the DFT/B3LYP/6-31G (d, p) method. In addition, the time-dependant density functional theory (TD-DFT) is used to study the optoelectronic properties and absorption spectra using DFT/CAM-B3LYP/ 6-31G +  + (d, p) level in the Gaussian 09 program. The highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), energy gap (E_g), light harvest efficiency (LHE), and open-circuit voltage (Voc) of the studied molecular structures are calculated and illustrated. These properties indicate that these molecular modeling structures as good candidates for utilization in organic DSSCs.

Exploration of Pull-Push Effect for Novel Photovoltaic Dyes with A-π-D Design: A DFT/TD-DFT Investigation

The π-rich versus π-poor units in 4,6-di(thiophen-2-yl)pyrimidine (DTB) alternating the π-backbone of solar cells dyes have been extended with a push-pull technique to lower their HOMO-LUMO energy gap and to increase Intramolecular Charge Transfer (ICT). Density functional theory was used to optimize the ground state molecular geometries of newly designed dyes (DTB1-DTB6). Time Dependent DFT (TD-DFT) was used to simulate the Uv-vis spectral values at the maximum absorbance values ranging between 481-535 nm. These values were red shifted from DTB value of experimental (333 nm) and theoretical (346 nm). however, their computed absorbance and fluorescence spectra revealed a bathochromic shift of them upon an increasing the solvent polarity. Different DFT functionals such as (B3LYP, CAM-B3LYP, B97XD, and APFD) were employed to choose their proper use Uv-visible analysis to reveal an unexpected coherence at the B3LYP level with experimental values. As a result, the B3LYP with most diffused basis sets of 6-31G + (d,p) were used for further calculations. The parameters of Global Chemical reactivities revealed that all the dyes had a softer nature with their softness value range of 0.27-0.41. their Ionization Potentials (IP) ranged between 6.21-8.10 eV to comply that the new dyes had good electron donating potentials. With a good electron injection potential of -1.47-1.74 eV, aluminum can be the best electrode, while Au is excellent towards a hole injection operation which had the potential range of 1.79-3.68 eV. For Natural Bond Orbital (NBO) assessment, (N14)LP → (F16-F28)π* with stabilization energy of 42.55 kcal/mol was noted for DTB4. Their Second order hyperpolarizability [Formula: see text] values as their Nonlinear Optical (NLO) response ranged between 59.16-232.11 debye-angstrom^-1 which were almost 6 times higher than the reference DTB (8.47D). The NLO attributes has also shown that a dyes with its small bandgap was related with higher hyperpolarizability values. Because of the decreased reorganization frequencies, newly discovered derivatives with electron transfer qualities might be comparable to or equivalent to those of commonly used electron transmission materials.