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A new complex formed from the reaction of benzene-1,2,4,5-tetracarboxylic dianhydride with zinc(II) acetate dihydrate was synthesized and characterized by single-crystal X-ray diffraction, thermal analysis (TGA), and density functional theory (DFT). [C10H4O8][Zn(H2O)6] (1), crystallized in a monoclinic system with space group P2/m. Theoretical modeling was performed at the DFT/B3LYP computational level with 6–311 G(d,p) and LanL2DZ basis sets. The Zn(II) is six-coordinate, forming an ideal octahedral geometry. A Hirshfeld surface analysis of the complex indicated that H···O/O···H contacts contribute to 47.8% of the crystal packing. The stability of 1 was investigated by determining the global chemical reactivity descriptors (GCRD). The nonlinear optical (NLO) behavior was investigated by analyzing the dipole moment, polarizability, and first-order hyperpolarizability (μ, α and β) via a theoretical approach, indicating that 1 has important nonlinear optical properties. A molecular docking study shows binding of 1 on the active site of receptors from human cyclooxygenase-2 enzyme (PDB code: 5IKT) and Escherichia coli MenB (PDB code: 3T88). [ABSTRACT FROM AUTHOR]

This work concerns a comparison of experimental and theoretical results of the electron charge density distribution and the electrostatic potential around the m-nitrophenol molecule (m-NPH) known for its interesting physical characteristics. The molecular experimental results have been obtained from a high-resolution X-ray diffraction study. Theoretical investigations were performed using the Density Functional Theory at B3LYP level of theory at 6-31G* in the Gaussian program. The multipolar model of Hansen and Coppens was used for the experimental electron charge density distribution around the molecule, while we used the DFT methods for the theoretical calculations. The electron charge density obtained in both methods allowed us to find out different molecular properties such us the electrostatic potential and the dipole moment, which were finally subject to a comparison leading to a good match obtained between both methods. The intramolecular charge transfer has also been confirmed by an HOMO-LUMO analysis.

In this work, a thiazole derivative, 5-(5-nitro furan-2-ylmethylen), 3-N-(2-methoxy phenyl),2-N'-(2-methoxyphenyl) imino thiazolidin-4-one (abbreviated by NF2MT), was characterized through Fourier transform infrared, UV–vis, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Besides, a complete and detailed vibrational assignment have been achieved by means of density functional theory (DFT) calculations using the B3LYP theory and the 6 311G(d,p) basis set. Based on the electron density distribution, reduced density gradient and atoms-in molecules analyses have been performed to describe and identify the intra- and intermolecular interactions within the molecule. Non-covalent interactivities between non-bonded atoms were also characterized. In addition, the frontier molecular orbitals and global chemical reactivity descriptors of NF2MT were further investigated using DFT, revealing the most important electronic properties of the compound. The TD-DFT method at CAM-B3LYP/6-311G(d,p) level with the chloroform solvent and polarized continuum model was applied to obtain optical behavior as well as the electronic transitions for the molecule. On the other hand, molecular properties such as atomic charges (Mulliken and NBO) and molecular electrostatic potential were calculated to locate the most reactive sites in the molecule that promote hydrogen bond formation. Molecular docking studies were also carried out to predict and display binding sites of NF2MT with its target protein. The biological activity was tested with acetylcholinesterase and butyrylcholinesterase. [ABSTRACT FROM AUTHOR]

The spectroscopic characterization of the new synthesized heterocyclic aromatic organic compound ethyl −2-{[4-ethyl −5-(quinolin- 8-yloxymethyl) -4H- 1,2,4-triazol −3-yl] sulfanyl} acetate (abbreviated by Q-tsa) was carried out using experimental FTIR, UV–Vis, 1H, and 13C NMR techniques. To support the analytical results, theoretical calculations were performed on Q-tsa using DFT method associated with B3LYP functional with 6-31G(d,p) and 6-311G(d,p) basis sets. Furthermore, the reactivity of the title compound was studied by the investigation of frontier molecular orbitals (FMO) analysis, HOMO-LUMO energies, density of state (DOS), molecular electrostatic potential (MEP), global and local chemical reactivity descriptors. Thermodynamic properties were separately computed and discussed. The attractive, repulsive and van der Waals strong and weak interactions in Q-tsa were performed via RDG analysis followed by the investigation of topological properties via AIM theory. Similarly, the NLO activity of the studied compound was highlighted by computing the first hyperpolarizability in different available solvents. Finally, through molecular docking, the biological activity of Q-tsa was studied and discussed. [ABSTRACT FROM AUTHOR]

AbstractA novel heterocyclic compound named (Z)-5-(4-nitrobenzylidene)-3-N(3-chlorophenyl)-2-thioxothiazolidin-4-one (NCTh) was synthesized and analyzed using various techniques, including single crystal X-ray diffraction, FT-IR, UV-Vis, NMR spectroscopy, and mass spectral data methods. NCTh was observed to crystallize in the triclinic crystal system P-1 space group. To validate the experimental findings, density functional theory (DFT) calculations were performed using the B3LYP functional with the 6-311 G(d,p) basis set. The results indicated good agreement in geometrical parameters between the experimental and theoretical outcomes. The study also calculated HOMO-LUMO energies, molecular electrostatic potential (MEP), and global chemical reactivity descriptors to evaluate the compound’s reactivity. Additionally, the study conducted reduced density gradient and Hirshfeld surface analyses to reveal attractive, repulsive, and van der Waals strong and weak interactions. The calculation of thermodynamic parameters was also included. The study focused on investigating the nonlinear optical (NLO) properties of NCTh, which were characterized through key parameters such as the electric dipole moment (µ), polarizability (α), first-order hyperpolarizability (β), and second-order hyperpolarizability (γ). These properties provide insights into the material’s potential applications in optical and photonic technologies. Additionally, a molecular docking study was performed to further explore the structure-activity relationship, particularly in a biological context. The docking results revealed a strong ligand-protein interaction, with a binding energy of −10.3 kcal/mol, indicating significant affinity. Moreover, the inhibition constant (Ki) was calculated to be 0.0281 μM, suggesting a highly potent interaction, which could be relevant for drug design or biochemical applications. [ABSTRACT FROM AUTHOR]

In the title compound, C26H21N3O5S, the thia­zole ring is nearly planar with a maximum deviation of 0.017 (2) Å, and is twisted with respect to the three benzene rings, making dihedral angles of 25.52 (12), 85.77 (12) and 81.85 (13)°. In the crystal, weak C--H⋯O hydrogen bonds and C--H⋯π inter­actions link the mol­ecules into a three-dimensional supra­molecular architecture. Aromatic π-π stacking is also observed between the parallel nitro­benzene rings of neighbouring mol­ecules, the centroid-to-centroid distance being 3.5872 (15) Å. [ABSTRACT FROM AUTHOR]