Global Reactivity Descriptors Research Articles

Theoretical Investigation of Substitution Effect on the First Position of Coumarin Derivatives

AbstractDensity functional theory (DFT) and time‐dependent DFT (TD‐DFT) were used to investigate the linear and nonlinear optical properties of 1‐substituted coumarins. The molecular electrostatic potential plot, frontier molecular orbitals, and natural bond order analysis were used to study charge transfer properties. The bandgap exhibited an inverse relationship with the chemical potential (µ) and electrophilicity index (ω), while the chemical hardness (η) and hyperhardness (Γ) showed a direct relationship. First‐order hyperpolarizability (β0) and second‐order hyperpolarizability (γ) were directly correlated with the global reactivity descriptors μ and ω and inversely correlated with η and Γ.

Synthesis, Crystal Structure, Intermolecular Interactions, HOMO-LUMO, MEP, NLO Properties, and DFT/TD-DFT Investigation of (Z)-5-(4-Nitrobenzylidene)-3-N(3-Chlorophenyl)-2-Thioxothiazolidin-4-One

A 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.

Catalytic behavior, electronic structure and spectroscopic (FT-IR, Raman, UV–vis) properties for the new ionic liquid imidazolium hydrogen sulfate

Catalytic performance, chemical reactivity, vibrational modes and electronic transitions of the ion pair [H–Im]+[HSO4]– were investigated in the current paper. Hence, a combined experimental (Hammett acidity function, infrared, Raman and ultraviolet-visible spectroscopies) and theoretical (molecular electrostatic potential surface, reduced density gradient, frontier molecular orbital analysis, quantum theory of atoms in molecules, net atomic charges, global and local reactivity descriptors) study was conducted. In terms of the catalytic performance, the acetic acid esterification with butanol was evaluated. Important kinetic (rate constant, activation energy, pre-exponential factor) and thermodynamic (enthalpy, entropy, Gibbs free energy barrier) factors for ester production as a function of the temperature and catalyst loading have been determined. Results revealed intensive electron density distribution in [H–Im]+[HSO4]– due to chemical interactions between the cationic and anionic moieties. These bonds were established as electrostatic in nature. The pronounced charge transfers within [H–Im]+[HSO4]– managed the title compound acidity (H0) and its catalytic behavior towards butyl acetate synthesis. Using the thermodynamic and kinetic measurements, a mechanism for acetic acid esterification with butanol in the presence of imidazolium hydrogen sulfate ionic liquid was offered.

Preyssler heteropolyacid-mediated direct deprotection/N-benzoylation of N-Boc-protected sulfonamides: synthesis, molecular docking, DFT study and in-silico ADME evaluation of novel benzamides bearing the sulfonamide moiety as possible inhibitors of human carbonic anhydrase II

An adequate method is described for the synthesis of new substituted benzamides containing a sulfonamide moiety using Preyssler heteropolyacid H14[NaP5W30O110] as an efficient catalyst. This method proceeds in one-step, including deprotection and benzoylation of N-(tert-butoxycarbonyl) sulfonamides to give the target compounds good yields (up to 92%). A molecular docking was performed to study the interactions between the synthesized benzamides and human carbonic anhydrases II. It was concluded that all compounds demonstrated good binding score values (up to −9.4 kcal/mol) for the active site of all selected proteins when compared with the reference drug Acetazolamide (−6.3 kcal/mol). In addition, the ADME/T analyses show that all synthesized molecules exhibited good pharmacokinetics and bioavailability. The theoretical calculations for all compounds were performed using the DFT/B3LYP/6–31G (d,p) level of theory. The study yielded optimized structural parameters, global reactivity descriptors, and Frontier Molecular Orbitals (FMO’s).

Experimental Spectroscopic and Computational Studies on A New Synthesized Sulfisoxazole Derivative; Molecular Docking, Drug-likeness, ADME, Toxicity Predictions and Carbonic Anhydrase II Activity Investigations

In this paper, 5-Dimethylamino-2-hydroxy-3-methoxy benzaldehyde sulfisoxazole (5DHMS) and Cu(5DHMS)2 compounds have been synthesized. The molecular structure characterizations were performed using experimental and computational methods. In the experimental part of the study, CHNS, FT-IR, NMR, TGA, and LC-MS analysis techniques were used. In the theoretical part, Density Functional Theory (DFT) was selected for the calculation level. Firstly, optimized structures were obtained from the predicted 3D structures. Vibrational modes were calculated using the optimized structures of the compounds. The vibrational modes of each compound were analyzed in detail using potential energy distribution (PED). Molecular electrostatic potential and HOMO-LUMO maps were drawn. Global chemical reactivity descriptors of compounds were determined. Moreover, the solvent media effects on chemical reactivity descriptors were revealed in detail. Protein-ligand interactions with the target receptor carbonic anhydrase II enzyme were performed. In addition, some important biological activity parameters such as drug-likeness, toxicity, and ADME predictions were examined in silico.

Synthesis, in vitro antibacterial and antioxidant evaluation, DFT calculation, molecular docking, and ADMET studies of novel N-Acyl-6-chloro-2(3H)-benzoxazolone derivatives

A new series of N-acyl-6-Chloro-2(3H)-benzoxazolone derivatives (4a-4g) were synthesized using an eco-friendly catalyst. The compounds were characterized using spectroscopic techniques, including FTIR, 1H NMR, 13C NMR, and GC–MS. Their antimicrobial activity against various bacterial strains, including both Gram-negative and Gram-positive bacteria, was evaluated and yielded promising results. The synthesized compounds were also tested for their antioxidant properties using the DPPH radical-scavenging method, where compound 4f exhibited the highest activity with an IC50 of 1.54 μg/mL, surpassing that of ascorbic acid (IC50 = 1.7 μg/mL). Additionally, DFT calculations were performed to investigate the compounds’ chemical reactivity, including the analysis of HOMO and LUMO frontier molecular orbitals, global reactivity descriptors, and molecular electrostatic potential. Molecular docking studies were conducted to explore the interactions between the synthesized compounds (4a-4g) and the standard drug ciprofloxacin at the active site of DNA gyrase. Furthermore, physicochemical properties, lipophilicity, water solubility, pharmacokinetics, drug-likeness, and medicinal chemistry properties were estimated using SwissADME. Toxicological profiles, including hepatotoxicity, carcinogenicity, immunotoxicity, mutagenicity, cytotoxicity, and LD50, were predicted using the ProTox-III web tool. The findings suggest potential therapeutic applications for combating bacterial strains, indicating that these synthesized compounds could serve as lead compounds for antibiotic drug development.

Unveiling the adsorption mechanism of propanehydrazine derivatives on magnesium oxide surface: Insights from computational approach

The use of green and effective inhibitors for preventing metal oxide (MgO) corrosion in industrial applications is highly significant in promoting environmental protection and sustainable development. This study delves into the adsorption behavior and interfacial mechanism of environmentally friendly inhibitor derived from propane hydrazine (PH) on MgO surface. Specifically, PH1, PH2, PH3, and PH4 were explored for their effectiveness in preventing corrosion by using advanced theoretical simulations-based density functional theory (DFT) for assessing the reactivity and adsorption characteristics. The study considered a detailed exploration of local and global reactivity descriptors, providing insights into the inhibitors’ reactivity and adsorption abilities in both isolated and adsorbed states. These findings focus more in the mechanisms underlying organic-inorganic interactions and present promising prospects for further development and application. Using first-principles DFT calculations alongside quantitative molecular surface analyses, we examined the adsorption patterns of PHs on the MgO(100) surface. These investigations are boosted by the application of independent gradient model (IGM) framework, providing robust verification of PHs' adsorption behavior on MgO(100) surface. Our calculations reveal a substantial decrease in the energy gap following complex formation, suggesting that charge density changes occur upon interaction with MgO surfaces, thereby facilitating direct electron transfer in all the studied systems. Noreover, the results highlight the crucial role of intermolecular interactions in boosting the interaction between PHs and the [Mg(H2O)6]2+ cation. First-principles DFT calculations show that all PH molecules consistently display parallel adsorption on the MgO surface, where the oxygen atoms form bonds with adjacent magnesium atoms. The bond lengths vary from 2.18 to 2.35 Å when PHs bind to the Mg atoms in parallel orientations through the oxygen atom, suggesting a stable parallel arrangement for PH molecules on the MgO surface. The calculated adsorption energy (Eads) varies in the following order: MgO-PH3 (−815.14 Kcal mol−1) > MgO-PH2 (−803.85 Kcal mol−1)) > MgO-PH4 (−695.38 Kcal mol−1) > MgO-PH1 (−125.77 Kcal mol−1). This trend indicates that parallel interactions enhance the adsorption behavior and binding of PH compounds through inter- and intra-molecular interactions, resulting in the PHs being centered at specific sites on the MgO surface. The potential enhancement in electrochemical properties is believed to stem from the synergistic interaction between the PHs and the MgO surface, which theoretically allows for a precise adjustment of their adsorption and interaction within the composite structure. This understanding provides a fundamental framework for examining the complex interfacial dynamics between inhibitor structures and elucidating how these molecular interactions influence the selection of corrosion inhibitors and their adsorption behaviors on the corrosion layer's surface, rather than on metallic Mg.

Electronic structure, global reactivity descriptors and nonlinear optical properties of glycine interacted with ZnO, MgO and CaO for bacterial detection

Modern laboratory medicine relies on analytical instruments for bacterial detection, focusing on biosensors and optical sensors for early disease diagnosis and treatment. Thus, Density Functional Theory (DFT) was utilized to study the reactivity of glycine interacted with metal oxides (ZnO, MgO, and CaO) for bacterial detection. Total dipole moment (TDM), frontier molecular orbitals (FMOs), FTIR spectroscopic data, electronic transition states, chemical reactivity descriptors, nonlinear optical (NLO) characteristics, and molecular electrostatic potential (MESP) were all investigated at the B3LYP/6–31G(d, p) level using DFT and Time-Dependent DFT (TD-DFT). The Coulomb-attenuating approach (CAM-B3LYP) was utilized to obtain theoretical electronic absorption spectra with the 6-31G(d, p) basis set to be more accurate than alternative quantum chemical calculation approaches, showing good agreement with the experimental data. The TDM and FMO investigation showed that glycine/CaO model has the highest TDM (10.129Debye) and lowest band gap (1.643 eV). The DFT computed IR and the experimental FTIR are consistent. The calculated UV-vis spectra showed a red shift with an increase in polarity following an increase in the absorption wavelength due to the interaction with ZnO, MgO, and CaO. Among the five solvents of water, methanol, ethanol, DMSO and acetone, the water and DMSO enhances the UV-Vis absorption. Glycine/CaO model showed high linear polarizability (14.629 × 10−24esu) and first hyperpolarizability (23.117 × 10−30esu), indicating its potential for nonlinear optical applications. The results showed that all model molecules, particularly glycine/CaO, contribute significantly to the development of materials with potential NLO features for sensor and optoelectronic applications. Additionally, MESP confirmed the increased electronegativity of the studied structures. Additionally, glycine/ZnO nanocomposite was synthesized and characterized using IR and UV-visible spectroscopy to determine their structural and spectroscopic features. It was discovered that there was good agreement between the DFT computed findings and the related experimental data. The antibacterial activity of glycine/ZnO nanocomposites against Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa were studied in terms of concentration and time. The results showed that increasing the concentration of glycine/ZnO nanocomposite significantly enhanced its antibacterial efficacy by lowering optical density. Notably, Pseudomonas aeruginosa exhibited lower susceptibility to the nanocomposite compared to S. aureus, requiring higher concentrations for effective bactericidal action. In summary, this study contributes novel insights into the dual functionality of glycine-metal oxide complexes, with significant implications as optical biosensor for microbial detection.

In Silico Investigation of Molecular Properties and Molecular Docking of Darunavir: An Anti‐HIV Drug

AbstractA second‐generation HIV protease enzyme inhibitor, darunavir is used in combination therapy for patients with history of prior antiretroviral treatments. It inhibits the cleavage of HIV encoded gag‐pol polyprotein in cells contaminated by a virus and thereby hinders the development of mature and infectious new virions. In this paper, optimization of molecular geometry of darunavir has been obtained by Density Functional Theory based B3LYP and ωB97XD methods with 6–311+G(d,p) basis set. The electro‐optical, global reactivity descriptors, and UV–visible spectrum of the drug have been examined using both the functionals. Further, binding affinity of darunavir at different sites of protein receptor (PDB ID: 5b18) has been analyzed using molecular docking technique. Results have been used to discuss electro‐optical and electronic properties of the drug along with its binding affinities with protein receptors.

Tuning the photophysical and NLO properties of β-diketonates derived from coumarin-triphenylamine-chalcones: effect of the BF2 group.

Herein the synthesis of three difluoroboron β-diketonate complexes (7a-c) and one chalcone (7d) with coumarin and triphenylamine fragments is described. The effect of the inclusion of the difluoroboron (BF2) group and a phenyl linker on the photophysical properties, intramolecular charge transfer (ICT) and nonlinear optical (NLO) properties was studied. These dyes exhibited excellent ICT properties due to their A-π-D and D-π-A-π-D type push-pull configuration. Thus, all compounds presented a strong solvatochromism, given the absorption and emission maxima shifted to red because of the increase in the polarity of the medium. In addition to this, 7a-d showed the formation of a twisted intramolecular charge transfer (TICT) state, which quenched fluorescence in polar solvents. Compounds 7a, 7b and 7d exhibited aggregation-induced emission (AIE) in MeCN/H2O mixtures, while 7c did not have this behavior. In addition, all compounds showed emission in the solid state. Using DFT and TD-DFT calculations, the molecular geometries of the ground state S0 and the first excited state S1 were elucidated, which confirmed the formation of a TICT state. Furthermore, the theoretical and experimental absorption electronic transitions were correlated by testing different functionals: B3LYP, CAM-B3LYP, PBE0, wB97XD, HSEH1PBE and M062X. Frontier molecular orbitals (FOMs) and molecular electrostatic potentials (MEPs) supported the ICT from the donor to the acceptor group. The global reactivity descriptors were studied and the NLO properties were predicted by calculating first (βtot) and second-order (γave) hyperpolarizabilities, revealing that 7a-d would present promising NLO behavior.

A density functional theory study of a series of symmetric dibenzylideneacetone analogues as potential chemical UV-filters

The aim of this research was to provide valuable insights on symmetrical α,β-unsaturated ketones as potential chemical ultraviolet (UV) filters from experimental data and theoretical aspects. Towards this end, density functional theory (DFT/B3LYP) calculations on a series of symmetrical α,β-unsaturated ketones, (1E,4E)-1,5-bis[4-(R)phenyl]penta-1,4-diene-3-one (R = methylthio, 1; R = dimethylamino, 2; R = ethyl, 3), were performed to determine the effect of different electron-donating substituents on their stability when exposed to solar UV radiation. Their molecular structures, and UV-visible, infrared (IR) and NMR (1H and 13C) spectra were theoretically obtained from their optimized geometries with the B3LYP/6-311++ G (d, p) basis set and were compared with the experimental results. Conformational analysis was performed and the most stable conformer of each compound was identified as the trans-trans conformer, which was further supported by experimental NMR data. The UV spectra and effect of solvent polarity and proticity were studied by the time-dependent-DFT (TD-DFT) approach with the B3LYP/6-311++G (d, p) level of theory. Furthermore, various molecular parameters like dipole moment, frontier molecular orbital (FMO) energies, ΔEHOMO-LUMO gap, lifetime of the first excited state (τ), global chemical reactivity descriptors, and natural bond orbital analysis were predicted at the same level of theory and compared with the experimental data. Inspection of the active FMOs revealed the photoinstability trends of 1 and 3 under UV irradiation. However, introducing a -N(CH3)2 substituent to 2 at the para-position improves its photostability towards simulated UV radiation. Thus, compound 2 has the potential to provide efficient broad-spectrum protection against UV radiation. This work has shown that molecular modelling strategies can assist to rationalize experimental findings and also support the identification of photoproducts of 1 and 3.

Density Functional Theory (DFT) Study on the Nontoxic Alternative of Bisphenol A (BPA) Derivatives: A Comprehensive Review

AbstractBisphenol A is an oil‐derived, large market volume chemical with a wide spectrum of applications in plastics, adhesives, and thermal papers. However, bisphenol A and its derivative are not considered safe due to its endocrine disrupting properties and reproductive toxicity. A nontoxic alternative of bisphenol analogus has been proposed in this study using plant biomass. A study of different DFT‐based QSAR approaches has been done to show the significance of the conceptual DFT‐based selected descriptors with different QSAR models in the prediction of toxicity and to establish meaningful correlations between the molecular structure of the proposed compounds and their toxicological properties. Multiple regression analysis and ANN model are also suggested to use to relate the biological activity with the global and local reactivity descriptors.

Triple Inhibition of SARS‐CoV‐2 by Rhenium(I) Acetylacetonato Tricarbonyl Phosphine Complexes: Structural Features, DFT Calculations, HS Analysis and In Silico Molecular Docking Study

AbstractTo gain insights into the activity of metal‐based drugs against SARS‐CoV‐2, five rhenium complexes, namely fac‐[Re(CO)3(acac)(PPh2Cy)] (I), fac‐[Re(CO)3(acac)(PPhCy2)] (II), fac‐[Re(CO)3(acac)(PCy3)] (III), fac‐[Re(CO)3(acac)(P(m‐tolyl)3)] (IV), and fac‐[Re(CO)3(acac)(P(p‐tolyl)3)] (V), with acac=acetylacetonato, PPh2Cy=cyclohexyldiphenylphosphine, PPhCy2=dicyclohexylphenylphosphine, PCy3=tricyclohexylphosphine, P(m‐tolyl)3=tri(m‐tolyl)phosphine, and P(p‐tolyl)3=tri(p‐tolyl)phosphine, were docked in the binding pockets of main protease, spike glycoprotein, and RNA‐dependent RNA polymerase. The resulting binding sites revealed potent SARS‐CoV‐2 inhibition, resulting from the formation of classical N−H⋅⋅⋅O and O−H⋅⋅⋅O hydrogen bonds, carbon C−H⋅⋅⋅O H‐bonds, hydrophobic contacts, as well as non‐conventional interactions such as weak C−H⋅⋅⋅N interactions, H⋅⋅⋅H, C⋅⋅⋅H/H⋅⋅⋅C, C⋅⋅⋅lp/lp⋅⋅⋅C and lp⋅⋅⋅lp contacts, cation‐π interactions and π⋅⋅⋅π stacking in the targets’ binding pockets. Moreover, we have optimized the molecular structures of these compounds using DFT methods and correlated them correspondingly to their crystal structures. We have estimated and evaluated the associated frontier molecular orbitals, as well as the global reactivity descriptors for which we have discussed the compounds’ reactivity. We have also examined intermolecular interactions by carrying out a Hirshfeld surface (HS) analysis, which showed the presence of C−H⋅⋅⋅H−C, C−H⋅⋅⋅C interactions, C−H⋅⋅⋅O non‐classical hydrogen bonds and π⋅⋅⋅π stacking, as well as non‐conventional π⋅⋅⋅lp and lp⋅⋅⋅lp interactions.

First Principle Studies of Electronic Properties, Global Reactivity Descriptors, and Molecular Docking of Olivacine Drug

AbstractOlivacine, a semisynthetic isomer of ellipticine, belongs to the family of natural alkaloids; which possess analgesic, antibacterial, and antipyretic properties. It is a model anticancer drug acting as topoisomerase II inhibitor. The mechanism of action and antineoplastic properties of olivacine are ascribed to its intercalative binding into DNA helices. The present paper reports DFT investigation of the molecular structure, electronic properties, and global reactivity descriptors of the drug. Frontier orbitals (HOMO and LUMO) and MEP surface of the olivacine molecule have been examined. Furthermore, inhibition activity and binding sites of olivacine with kinase protein (PDB Id: 3OG7) have been explored by molecular docking technique. Results have been used to elucidate physico‐chemical aspects and preferred binding patterns of the olivacine drug.

Synthesis, spectral analysis, and DFT studies of the novel pyrano[3,2-c] quinoline-based 1,3,4-thiadiazole for enhanced solar cell performance

In this study, we synthesized a novel compound, 3-(5-amino-1,3,4-thiadiazol-2-yl)-6-ethyl-4-hydroxy-2H-pyrano[3,2-c]quinoline-2,5(6H)-dione (ATEHPQ), through a condensation reaction between 6-ethyl-4-hydroxy-2,5-dioxo-5,6-dihydro-2H-pyrano [3,2-c]quinoline-3-carboxaldehyde and thiosemicarbazide, followed by oxidative cyclization. We characterized ATEHPQ using elemental analysis, IR, 1H and 13C NMR spectroscopy, and mass spectrometry. Density Functional Theory (DFT) calculations with the B3LYP/6–311++G(d,p) basis set were employed to optimize the molecular geometry and analyze global reactivity descriptors, including HOMO-LUMO energies. The Molecular Electrostatic Potential (MEP) map was used to identify reactive sites, and drug-likeness studies indicated potential pharmaceutical applications. Notably, ATEHPQ showed a higher first hyperpolarizability (βtot) compared to urea, suggesting its suitability for nonlinear optical applications. We also determined the Miller indices for ATEHPQ's preferred orientations using a specialized program. Williamson–Hall analysis revealed an average crystal size of 26.08 nm and a lattice strain of 6.3 × 10−3. The thin films exhibited three distinct absorption peaks at 2.8, 3.41, and 4.21 eV, with a direct energy gap of 2.43 eV. Dispersion parameters from the single oscillator model provided oscillator and dispersion energies of 3.12 eV and 14.21 eV, respectively, with a high-frequency dielectric constant of 4.71. The ATEHPQ thin films, when combined with n-Si, demonstrated significant improvements in photovoltaic performance: the open-circuit voltage (Voc) rose from 0.13 V to 0.521 V, the short-circuit current (Isc) increased from 0.253 mA to 2.94 mA, the fill factor (FF) improved from 0.238 to 0.33, and the efficiency (η) grew from 0.71 % to 4.64 % with increased illumination intensity. These results highlight the excellent photovoltaic and photodetection capabilities of ATEHPQ thin films, underscoring their potential for advanced optoelectronic and solar cell applications.

N-(4-(1,3-benzothiazol-2-ylcarbamoyl)phenyl)isonicotinamide as corrosion mitigator for mild steel in 1 M HCl: A multifaceted study integrating synthesis, characterization, and molecular modelling

Newly synthesized, cost-effective corrosion inhibitor, N-(4-(1,3-benzothiazol-2-ylcarbamoyl)phenyl)isonicotinamide (BIA) was evaluated for mild steel/1M HCl interface. BIA showed a maximum inhibition efficiency of 90.40 % at 100 ppm and 303 ± 1 K, with efficiency increasing with concentration but decreasing with temperature. Inhibitor’s adsorption followed Langmuir isotherm via physicochemical interactions. Activation parameters revealed BIA retards both metal dissolution and hydrogen evolution held in unimolecular process. Potentiodynamic polarization (PDP) divulged BIA as a mixed-type, impeding charge-transfer. Electrochemical impedance spectra (EIS) confirmed BIA forms a protective double layer, blocking active sites at the interface. Surface analysis supported a protective film formation. Global and local reactivity descriptors using DFT/B3LYP/6-311G++(d,p) were calculated to relate inhibition efficiency with BIA’s electronic properties. Molecular dynamics simulation (MDS) showed an interaction energy of −224.7 kJ/mol between BIA and Fe(110) at 303 K, with Radial Distribution Function (RDF) showing bond lengths under 3.5 Å, confirming a chemical interaction. Theoretical results align with experimental data.

Exploring the Effectiveness of 3-Chloro-4-morpholin-4-yl-1,2,5-thiadiazole as a Eco-Friendly Corrosion Inhibitor for Mild Steel in HCl Solution: Experimental and DFT Analysis

Corrosion is a significant issue in many industries, particularly where metals are exposed to harsh chemical environments. This study investigates the efficacy of 3-Chloro-4-morpholin-4-yl-1,2,5-thiadiazole (CMTD) as a corrosion inhibitor for mild steel in 1 M HCl solution across a temperature range of 303–333 K. Using weight loss measurements, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization techniques, the inhibition efficiency of CMTD was evaluated at different concentrations and temperatures. The results show that CMTD achieves a maximum inhibition efficiency of 96.8% at a highest inhibitor concentration, even at elevated temperatures. The adsorption of CMTD on the mild steel surface follows the Langmuir adsorption isotherm, with a calculated free energy of adsorption (ΔGads) of -39.5 kJ/mol, confirming a spontaneous chemisorption process. Quantum chemical Density Functional Theory (DFT) studies further elucidated the relationship between CMTD's molecular structure and its inhibition efficiency. Key parameters, including the energy gap (Egap = 3.551 eV), highest occupied molecular orbital (EHOMO = -6.317 eV), and lowest unoccupied molecular orbital (ELUMO = -2.766eV), were calculated to understand CMTD's reactivity. Additionally, global reactivity descriptors such as chemical hardness (η), electronegativity (χ), and the electron fraction transferred (ΔN) from CMTD to the iron surface were analyzed. These findings suggest that CMTD is highly effective in preventing corrosion and can be applied in industries where mild steel is exposed to acidic environments, such as in petrochemical and industrial cleaning processes.

Novel therapeutic agents for H5N1 influenza virus through 3D-QSAR, molecular docking, ADMET prediction, and DFT based global reactivity descriptors

Avian influenza is a severe respiratory disease that can cause catastrophic outbreaks in domestic poultry and wild birds as well as significant risks to people. This has motivated many researchers to develop new, effective neuraminidase (NA) inhibitors to treat this serious infection. In this context, this study aims to develop new potential NA inhibitors using five computational methods. A three-dimensional quantitative structure-activity relationship (3D-QSAR) comparative molecular similarity indices analysis (CoMSIA) was performed on a set of N-substituted Oseltamivir derivatives as anti-influenza agents. As a result, the best CoMSIA model was robust and predictive (R2 = 0.966, Q2 = 0.772, and Rpred2 = 0.721). Based on the contour map analysis, 17 new NA inhibitors with high-predicted inhibitory activity were developed. Molecular docking was used to discover the binding modes and interactions between the 17 newly designed NA compounds and the corresponding NA protein. Based on the absorption, distribution, metabolism, elimination, and toxicity (ADMET) properties, the compounds C10, C11, C12, C15, C16, and C17 have good drug-likeness and pharmacokinetics properties and could be new promising anti-influenza drugs. The six leading compounds further went through biological activity spectra prediction and quantum method density functional theory (DFT) study, which confirmed the trends and the utility of 3D-QSAR CoMSIA and molecular docking in developing new NA inhibitors.

The functional moieties impact on optical, thermal, and nonlinear properties of chalcone derivatives. A comprehensive study on FT2MP

This study explains the intricate interplay between functional groups and the single crystal structure of the compound 1-(furan-2-yl)-3-(2,4,6-trimethoxyphenyl)prop-2-en-1-one (FT2MP) using Density Functional Theory (DFT) calculations. Notably, geometry optimization at B3LYP using 6-311G+(2d,p) closely aligned with experimental distances from X-ray diffraction (XRD) upon comparison. A Q-switched, frequency-doubled pulsed Nd. YAG laser (532 nm, 7 ns pulses), a 25 cm focal length lens, and a 0.001 mol/L FT2MP solution in Dimethylformamide was used to measure third-order nonlinear optical (NLO) parameters and subsequently the origin of second/third harmonic generation efficiency is discussed. The third-order nonlinear parameters of FT2MP were found to be Δɸ = 0.95, n2 = −9.605 × 10−9 cm2/W, β = 2.74 × 10−6 cm/W, and χ(3) = 5.58 × 10−7 esu. Information about the electronic structure and reactivity of the molecule is provided via the addition of Global Chemical Reactivity Descriptors (GCRD), molecular electrostatic potential (MEP) and Frontier Molecular Orbitals (FMOs) for electronic structure and reactivity insights. Hirshfeld surface analysis was used to study intermolecular interactions. This investigation indicates the potential of FT2MP for third harmonic generation, providing a comprehensive understanding of its molecular structure, reactivity, and intermolecular interactions.

Synthesis and Density Functional Theory Study on the Functionalization of Carbon Nanotube Conjugates with Amino Compounds and Their Application in Dyeing Processes

AbstractThis study investigates the functionalization of graphene nanotube (GNTs) conjugates with an amino compound called 1‐amino‐2‐hydroxy‐4‐naphthalene sulfonic acid (AHNSA‐GNTs). The study also evaluates the potential application of these conjugates in dyeing processes. The goal is to modify GNTs to enhance their interaction with dyes, thus improving the efficiency of dyeing textiles and the colorfastness of the resulting products. Multiple characterization methods, such as X‐ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used to get a better look at the composites. The findings of the study indicate that AHNSA‐GNTs composites improve dye retention on wool fibers, which leads to a reduction in the consumption of excess dye and water. Density Functional Theory (DFT) calculations were utilized to investigate the electronic properties and binding energies of the functionalized CNTs, providing insights into the molecular interactions between the CNTs and amino compounds. Overall, this study highlights the promising applications of graphene nanotubes in sustainable textile processes. Frontier molecular orbitals (FMOs) and global reactivity descriptors serve as key tools for understanding the stability and chemical reactivity of compounds. These tools were used to calculate FMOs and electronic parameters of compounds 1 and 2 at the B3LYP/6‐31G(d) level of theory. The study examined the highest occupied molecular orbital (HOMO)‐lowest unoccupied molecular orbital (LUMO) energy gap, which provides insights into molecular stability and reactivity. Various physical properties were derived from these calculations, including electron affinity (EA) and ionization potential (IP) to LUMO and HOMO energies. Compound 2 emerged as the most efficient electron donor, possessing the highest HOMO energy, while compound 1 excelled as the best electron acceptor with the highest LUMO energy.