Global Reactivity Descriptors Research Articles

Regioselective Synthesis of 2,4- and 2,5-Disubstituted 1,3-Thiazoles from 2-Oxo-2-(amino)ethanedithioates via Base-Catalyzed Cyclization

AbstractFacile and efficient methods are reported for the synthesis of 2,4- and 2,5-disubstituted-1,3-thiazoles by the cyclization of 2-oxo-2-(amino)ethanedithioates with TosMIC and α-haloketones in high yields. Key structures were confirmed based on X-ray crystallographic studies. In addition, investigation of ground state geometry, electronic and molecular structural properties, FMOs, global reactivity descriptors, MEP and NCI analyses were predicted to access the information related to the stability, reactivity, and strength of the interactions present in the molecules by quantum chemical calculations. Further, the potency of derivatives was tested against the SARS-Cov2 receptor (PDB ID: 7mc6) via molecular docking approach with binding scores of –6.0 to –8.4 kcal/mol.

Quantum modelling of multi-directional fused-ring electron acceptors for organic photovoltaics

Multi-directional fused-ring electron acceptors (FREAs) feature a fused-ring backbone that extends in multiple directions through bridging and acceptor units. This unique structural design imparts several advantageous properties, like increased light absorption, precise energy level adjustments, improved electron mobility, reduced energy loss, and enhanced efficiency in organic photovoltaic (OPV) devices. In this study, we designed seven novel multi-directional FREAs and conducted a comprehensive computational analysis using Density Functional Theory (DFT) and Time-Dependent DFT (TD-DFT). The designed molecules feature a benzotrithienopyrrole central core connected to a π-bridge acceptor, either benzothiadiazole or benzotriazole, and three varying terminal acceptors, including malononitrile, 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile, and 2-(3-methyl-4-oxothiazolidin-2-ylidene)malononitrile. Our investigation encompassed the evaluation of geometry, frontier molecular orbitals (FMOs), optical properties, density of states (DOS), charge mobilities, dipole moment, global reactivity descriptors, molecular electrostatic potential (MEP), transition density matrix (TDM), and OPV device-related parameters. The results revealed significant potential of the designed molecules as FREAs for OPVs, thus highlighting their suitability for further experimental exploration.

In-depth Hirschfeld Surface Analysis, Interaction Energy, Molecular Docking, and DFT Investigations of Electronic Properties of 2,4-dimethyl-1-nitrobenzene

Quantum-chemical calculations, molecular docking, and Hirshfeld surface analysis of a structure of 2,4-dimethyl-1-nitrobenzene constitute the main aspects of this work. The crystal structure of the title compound which is liquid at room temperature, was obtained by in situ cryo crystallization The crystal packing is stabilized by C5–H5…O2 and C7–H7C…N1 intermolecular hydrogen bonds. The analysis of the obtained results of the density functional theory calculations is in good agreement with the experimental data. The analysis of global chemical reactivity descriptors shows that the compound exhibits more stability and less reactivity at high polar media. Hirshfeld surface and 2D-fingerprint plots analysis shows that the H…H, O…H/H…O, C…C, and C…H/H…C contacts are the significant contributors stabilizing the crystal structure of 2,4-dimethyl-1-nitrobenzene. The RDG-NCI analysis of the molecule was performed to determine the non-covalent interactions present within the molecule. In addition, the compound under investigation presents a biological activity when it is docked into the protein (PDB ID: 4Y0S) with the binding energy system of -6.6 kcal/mol.

Synthesis, antimicrobial, DFT, and in silico pharmacokinetic profiling of nitroaldol quinoline derivatives: A comprehensive exploration for designing potential oral antibacterial agents targeting DNA-gyrase

This study presents a thorough exploration of the synthesis, biological activities, and molecular properties of a novel series of β-nitroaldol quinoline derivatives (4a-4i). Structural characterization utilized FTIR, 1H NMR, 13C NMR, and mass spectrometry, providing a comprehensive understanding of the synthesized derivatives. Moreover, anti-microbial properties were evaluated using agar disk diffusion assay against five pathogenic strains, including Gram-negative and Gram-positive bacteria, as well as a fungal strain. Notably, compound 4e demonstrated strong anti-fungal and anti-bacterial activities (MIC = 25 µg/ml). A detailed analysis of molecular orbitals, total density of state, vibrational characteristics, global reactivity descriptors, molecular electrostatic potential, topological QTAIM analysis, and molecular docking provided nuanced insights into the reactivity, electronic properties, and potential interactions of the synthesized compounds. These findings contribute valuable information to the design and synthesis of compounds targeting bacterial DNA-gyrase. Furthermore, in silico predictions using the SwissADME online server indicated that all compounds comply with Lipinski's rule of five, suggesting their potential as orally active drugs. The compounds demonstrated commendable water solubility, passed various filters, and exhibited bioavailability scores, indicating promising oral bioavailability. The percentage of oral absorption ranged from 75.39% to 78.58%, signifying high permeability. Computational analysis of pharmacokinetic parameters revealed favorable characteristics, including gastrointestinal absorption and minimal inhibitory effects on specific enzymes.

Unraveling the sorption mechanisms of ciprofloxacin on the surface of zeolite 4A (001) in aqueous medium by DFT and MC approaches

The adsorption mechanism of ciprofloxacin (CIP) and its ionic form were investigated using density functional theory (DFT) and molecular dynamics (MD), with the goal of forecasting their adsorption behavior in terms of gap energy, global reactivity descriptors, Fukui functions, adsorption energies, and density of state on the surface of zeolite 4A (001). Quantum chemical parameters related to the adsorption process were calculated, as well as the overall reactivity. According to DFT calculations, the zwetterionic form CIP± are the most stable and reactive and have a greater power of electron transfer compared to the other species. Under aqueous conditions, zeolite can adsorb ciprofloxacin (CIP) and its ionic forms, as revealed by molecular dynamics simulation. Ciprofloxacin in the zwitterionic form (CIP±) were more efficiently adsorbed to the surface of zeolite 4A (001) than the cationic (CIP+), anionic (CIP−), and neutral(CIP) forms; through the evaluation of adsorption energy, probability distribution, interaction, and density of state. The results also demonstrated that the compounds studied were adsorbed via the process of chemical bonding, which was confirmed by the negative values of the interaction energy. Furthermore, the negative adsorption energy values suggest a significant adsorption of all compounds, with electrostatic interactions (physisorption), diffusion into the pores, and n-π bonds (chemisorption) on the zeolite surface. The increase in adsorption energies and the proximity of the molecules studied to the zeolite surface indicate the predominance of chemisorption, and the adsorption of ciprofloxacin was found to be an exothermic and spontaneous process. Molecular dynamics (MD) modeling was in agreement with the DFT results.

Synthesis, Thermal, DFT Calculations, HOMO-LUMO, MEP, and Molecular Docking Analysis of New Derivatives of Imidazolin-4-Ones

This work focuses on synthesizing new imidazolin-4-one derivatives (2a-c), akin to leucettamine B analogs, via microwave-assisted transamination reactions. This reaction was carried out between 3-alkyl-5-dimethylamino-2-thioxo-imidazolidin-4-one (1a-c) and aniline. The structural integrity of the synthesized compounds was confirmed using NMR and MS spectroscopy, and their configurations were validated through DFT calculations. Analyses encompassed molecular electrostatic potential, frontier molecular orbitals, HOMO-LUMO energies, energy band gap, and global chemical reactivity descriptors, providing comprehensive insights into their characteristics. The investigation extended to the biological domain, employing substance activity spectra prediction (PASS) and molecular docking with Autodock Vina4 program. Notably, this holistic assessment aimed to gauge the potential regulatory effect of the compounds on cholesterol. This integrated approach contributes to compound design understanding and potential applications, spanning drug design and broader biomedical contexts.

Theoretical investigation of the vibrational and electronic properties of tetraphenylammonium and its boron, aluminum, gallium, carbon, silicon, germane, phosphorus and arsenic analogues

Tetraphenyl ammonium (Ph4N+ ) has long been considered a phantom ion due to the difficulty in synthesizing aryl ammonium compounds. Following the successful synthesis of Ph4N+ last year (2022), the equilibrium geometries of Ph4X (X = B-, Al-, and Ga- of group 13; C, Si, and Ge of group 14; and P+ and As+ of group 15) have been optimized using the B3LYP/6-31G(d,p) method with no symmetry constraints. According to the optimized structural data, Ph4N+ is considered the most sterically hindered molecule in this series of compounds, which reflects the difficulty of its synthesis. The calculated total energies of the Ph4X compounds reveal that their energies decrease down the group, and the cationic forms (group 15) are less energetic than their neutral (group 14) and anionic (group 13) counterparts. The optimized geometrical parameters were used to compute the UV–vis, IR, 1H NMR, and 13C NMR spectra of the nine terephenyl compounds. The frontier molecular orbital energies were used to determine ionization potentials, electron affinity, and other global reactivity descriptors of the nine Ph4X compounds. An accurate assignment of vibrational bands was made using the potential energy distribution (PED) method. The B3LYP/6-31G(d,p) method yielded good agreement with available experimental data for the molecules. The low HOMO-LUMO gaps suggest potential nonlinear optical properties of these compounds.

Understanding the behavior of 5, 10, 15, 20-tetrakis (4 -hydroxyphenyl) porphyrin and its cation in Methanol: insights from electronic structure calculations

This research investigates the solvation dynamics and interactions of neutral 5,10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (TPPH) and its cationic form (TPPH2+) with methanol as the solvent. HOMO-LUMO analysis and Global Chemical Reactive Descriptors (GCRD) results were reported using DFT method with BP86 functional. The study reveals contrasting charge transfer behaviors: neutral TPPH demonstrates an enhanced charge transfer rate upon dissolution in methanol, while cationic TPPH exhibits a reverse trend. This solvation-induced reduction in energy gap presents a potential avenue for optimizing optoelectronic devices like light-emitting diodes and laser diodes. These findings elucidate the intricate interplay between porphyrin derivatives and solvents, offering valuable insights for tailored applications across diverse scientific and technological fields.

Combined spectroscopic and quantum chemical study to explore the effect of hydrogen bonding in hydrochlorothiazide-nicotinamide cocrystal

The present work focuses on the study of structural, vibrational, chemical properties and the effect of hydrogen bonding interaction in the formation of a cocrystal of hydrochlorothiazide (HCTZ, a diuretic drug) with nicotinamide (NCT) using vibrational spectroscopy (FT-IR and FT-Raman) and density functional theory. HCTZ being a BCS class IV drug, has low permeability and solubility; therefore, its cocrystal is studied. Monomer, dimer and trimer of HCTZ-NCT cocrystal were studied to understand hydrogen bonding interactions. The shifting in the wavenumber and the elongation in bond lengths of the amide (NH2) group of HCTZ and carbonyl (C = O) group of NCT were observed in all the models of HCTZ-NCT cocrystal due to the hydrogen bonding interaction. The importance of hydrogen bonding were also explored by natural bond orbital (NBO) analysis in support of the quantum theory of atom in molecules (QTAIM). The chemical reactivity of HCTZ, NCT and HCTZ-NCT cocrystal was examined by MEPS map, FMOs, global electronic reactivity descriptor, ECT descriptors, and molar refractivity. The lesser value of the HOMO-LUMO energy gap in the cocrystal than API reflects that the chemical reactivity of the cocrystal was better than API itself. The comparison between API(HCTZ) and cocrystal (HCTZ-NCT) implies that pharmaceutical cocrystals may be a better option to improve and enhance the pharmacological properties of drugs.

Towards designing of some potential new autoimmune disorder inhibitors using crystal structures and Hirshfeld surface analyses in combination with molecular docking and molecular dynamics simulations

The emergence of multi-drug-resistant autoimmune diseases poses a significant risk to human health and has garnered global attention. In this study, metformin and sulfasalazine have been used as starting materials or control. This research has successfully designed a hundred compounds, to assess their efficacy against two autoimmune disease pathogens: type 1 diabetes and rheumatoid arthritis. The DFT method was engaged to calculate the vibrational frequencies and Frontier Molecular orbitals (FMOs) of the selected compounds. The reactivity and selectivity of the selected compounds are analyzed using parameters like MEP and global reactivity descriptors, which are calculated and interpreted. The Density of state (DOS) of the molecule has been plotted and interpreted. Furthermore, docking results showed favorable interactions of the designed compound D385 with catalytically important amino acid residues. The interactions of the best active D385 when compared with the template and the standard drugs show similar binding sites. DFT studies further confirm the presence of HOMO orbital centered on the isoxazole ring further highlighting its importance for receptor-ligand hydrogen and hydrophobic interactions. The molecular dynamics simulations and MM/GBSA analysis reveal that the inhibitory nature of the designed compound D385 is a proven inhibitor of diabetes type 1 and rheumatoid arthritis inhibitor activities. Our study suggested that the designed compounds showed comparable results to that of metformin and sulfasalazine and may be used for further experimental studies. It can also be used as a pipeline to search for and design new potential autoimmune disease inhibitors. The most promising candidates from computational trials can be examined in a wet laboratory experiment before moving on to clinical trials.

Study of different interactions in piperazine benzoate and its effect on biological properties: Experimental and theoretical approach

Piperazine benzoate (PPB), an antibacterial molecule, was synthesized and characterized using FT-IR, FT-Raman, UV, and NMR spectra as well as biological research. The optimized geometry of the molecule was performed using Gaussian'09w programme at B3LYP with 6–311G++(d,p) basis set. Hyper conjugative interaction σ(CH) → σ*(OH) enhances NH…O interaction and C-H…O interaction arises mainly from charge transfer between the molecules. The electronic transitions in the molecule were exhibited by comparing the UV–vis spectrum with the observed spectrum using the TD-DFT method in gaseous phase. FMO analysis, natural charge analysis, and global chemical reactivity descriptors methods were investigated. PPB is a soft molecule with significant polarizability and chemical reactivity because of its low molecular orbital energy gap. Normal coordinate analysis (NCA) was used to determine the detailed interpretation of the fundamental modes. The chemical shifts of the molecule were determined from the recorded 13C and 1H NMR spectra using the gauge independent atomic orbital (GIAO) method. Using NBO analysis, concerns related to molecular stability and bond strength have been presented. The topological properties were studied using MEP, ELF, and LOL maps. From AIM findings, the PPB is defined by two BCPs, one each for an ON…H and CO…H type hydrogen bond. Through RDG investigation, the interactions inside the PPB molecule were examined. The interaction areas in the molecular structure of PPB are confirmed by the RDG graph data. PPB's absorption rate was 78.18 percent. This figure led to the conclusion that PPB had the highest percentage of absorption. Bacterial proteins were used for molecular docking, and docking parameters were derived. Based on Lipinski's rule of five, drug similarity was determined, and the ADMET variables were also predicted.

Spectroscopic properties (FT-IR, NMR and UV) and DFT studies of amodiaquine

Amodiaquine (AQ) was synthesized by a condensation reaction and characterized by experimental FT-IR, 1H and 13C nuclear magnetic resonance (NMR) and UV spectroscopies. In the present work, Density Functional Theory (DFT) calculations using B3LYP method with 6–311++G(d,p) and 6–311++G(2d, p) basis sets were performed, first, to confirm its structure, then to explain its reactive nature through its molecular properties such as natural charges, local and global reactivity descriptors or natural bond orbital (NBO). The 1H and 13C NMR chemical shifts were calculated by using the gauge-independent atomic orbital (GIAO) method, while the electronic UV–Vis spectrum is predicted using the time-dependent density functional theory (TD-DFT). Globally, the computerized results showed close similarity with the experimental values.The calculated energy band gap (ELUMO-EHOMO) value of AQ was found to be 4.09 eV suggesting that it could be considered as a hard molecule with high stability, supported by global reactivity descriptors. Molecular electrostatic potential (MEP) analysis revealed heteroatoms (oxygen and nitrogen) as the most putative nucleophilic sites when hydrogen atoms to which they are linked appear as electrophilic sites. The potential use of amodiaquine as non-linear optical (NLO) material and its thermodynamic indicators have also been assessed.

Monohalogenated methyl- and methoxy-benzoic acids: A combined experimental and quantum chemical theoretical study on their structure, vibrational analysis and molecular parameters

In this paper, the molecules 3-fluoro-2-methylbenzoic acid; 3-chloro-2-methoxybenzoic acid; and 3-bromo-2-methylbenzoic were investigated using experimental and quantum chemical theoretical approach for vibrational and electronic properties from the optimized structure. Becke three parameter Lee–Yang–Parr density functionals along with 6-311++G(d,p) basis set were employed to compute their geometric optimization, fundamental frequencies and molecular parameters. The detected FT-IR and FT-Raman spectra were compared with their simulated spectra and the rms error between the detected and simulated vibrational frequencies was found at 6.17, 7.22 and 6.76 cm−1 for FMA, CMA and BMA, respectively. All the vibrational fundamentals were assigned unequivocally using potential energy distribution (PED) obtained in the computations. 1H and 13C NMR chemical shifts were evaluated by integrating the gauge-independent atomic orbital (GIAO) method with DFT and compared with corresponding experimental values. TD-DFT approach was followed to compare the simulated absorption maxima (λmax) in DMSO-d6 solvent with observed values and interpreted in terms of HOMO and LUMO. The global reactive descriptors were estimated from the associated energies of HOMO and LUMO which describe the reactivity and stability of the molecules. Molecular electrostatic potential (MEP) surface has been determined using the charge density distributions to demonstrate electrophilic and nucleophilic nature of the molecules. DFT computations also ascertained the applicability of the titled molecules as NLO materials from the computed values of dipole moment and hyperpolarizability. Thermodynamic parameters and rotational constants were also evaluated employing rigid rotor harmonic oscillator approximation. Natural bond orbital (NBO) analysis confirmed the charge delocalization due to intra-molecular interactions.

X-ray Diffraction, Spectroscopy, Optical Properties, NPA, NBO, FMO, and Hirshfeld Surface Analyses of Two Newly Synthesized Piperidinium Ionic Liquids

The present study elaborates on the synthesis, crystal structure, and computational studies of two new ionic liquids. In the crystal structure, [C5H12N][C21H14ClN2O2S] (4a), the anions form chains along the a-axis direction through C—H···π(ring) interactions. These are connected into layers that run approximately parallel to the ac plane by a variety of hydrogen bonds. In the compound structure, [C5H12N][C18H15N2O2S] (4b), the two ions are primarily associated by an N—H···N hydrogen bond. In the crystal structure, layers parallel to the bc plane are formed by pairs of C—H···O and N—H···S hydrogen bonds and by C—H···π(ring) interactions. A theoretical study reveals that 4a has lower energy than 4b and is more stable. The NBO and DOS studies further confine the liquids’ structural reactivity and electronic properties. The quantum theory of atoms in a molecule (QTAIM) analysis reveals the important non-covalent interactions among the fragments and charge transfer. The global reactivity descriptors indicate their molecular reactivity relationship with the presence of functional groups. The remarkable polarizability (αo) and hyperpolarizability (βo) values indicate their optical and nonlinear optical (NLO) properties. Furthermore, the analysis performed by CrystalExplorer shows the intermolecular interactions and reactive sites between cations and anions in ionic liquids. The 2D fingerprint plots and Hirshfeld surfaces indicate the major interactions of crystals with neighboring elements in crystal packing. For both compounds, the H···H interactions are significantly higher than the other element interactions.

Ring opening ring closure reactions with 5,9-diethyl-7-(chromon-3-yl)-7-hydroquinolino[3′,4′:5,6]pyrano[3,2-c]quinoline-6,8(5H,9H)-dione with some 1,2-binucleophiles: Synthesis, characterization, DFT study and biological activity

The chemical behaviour of electron deficient substrate 1 was investigated with some 1,2-bi-nucleophilic reagents. Reaction of substrate 1 with hydrazine derivatives namely hydrazine hydrate, phenylhydrazine, 7‑chloro-4-hydrazinoquinoline and 3-hydrazino-5,6-diphenyl-1,2,4-triazine led to 7-pyrazolylquinolinopyranoquinolines 2, 3, 6 and 7, respectively. These reactions proceed through γ-pyrone ring opening followed by pyrazole ring closure. Moreover, treating compound 1 with hydroxylamine hydrochloride provided 7-isoxazolylquinolino[3′,4′:5,6]pyrano[3,2-c]quinoline 8. The molecular structures were optimized utilizing DFT/B3LYP functional with 6–311G+(d,p) basis sets for all compounds. Moreover, global reactivity descriptors like chemical potential (μ), electronegativity (χ), hardness (η), softness (S) and electrophilicity index (ω) were computed to predict the chemical reactivity and kinetic stability of the synthesized compounds. The locations susceptible to attack by electrophiles and nucleophiles were examined at the same theoretical level by using molecular electrostatic potential (MEP) and condensed Fukui functions. The NMR chemical shifts were computed by the Gauge Independent Atomic Orbital (GIAO) method and compared to the experimental results. The first hyperpolarizability of the prepared compounds is higher than urea, so serves as good candidate for nonlinear optical (NLO) materials. The synthesized substances were tested for their efficacy as antimicrobial agents against a variety of bacterial and fungal species. Additionally, the present compounds revealed some antitumor activity (compounds 3 and 7 showed activity comparable to cis-platin, used as a reference drug in the assay). Furthermore, the synthesized compounds were moderately compliant with Lipinski's rule of five, suggesting that related compounds might be suitable for oral administration as medications.

Investigation on the stability of the Enol Tautomer of Favipiravir and its derivatives by DFT, QTAIM, NBO, NLO and 1H-NMR

Relative stability energies of enol and keto forms of Favipiravir drug (6-fluoro-3-hydroxy-2-pyrazine carboxamide) and its twelve derivatives were theoretically envisaged using the B3LYP/6-311 + G(3df,2p)//B3LYP/6-311 + G(d,p) level of theory. Influence of the nature of the substituted groups on the geometric structures, IMHB, vibrational frequencies, dipole moments, and global reactivity descriptors was systematically studied. The enol form was found to be more stable than the keto form, regardless of the nature of the substituted group, by an average of 12.5 and 5.4 kcal/mol in the gas phase and in the aqueous solution, respectively. The role of the IMHB strength in the stability of the enol form compared with the keto form was investigated in terms of QTAIM and NBO analysis and 1H NMR chemical shifts. The NLO properties at CAM-B3LYP with 6-311 + G(d,p) basis set of the two forms and their derivatives were also used to explain the relative stability.

Synthesis, Spectroscopic Characterization, DFT, and Molecular Docking Analysis of Some Salicylideneaniline Schiff Base Derivatives as Potential Antioxidant Compounds

This study explores the synthesis and characterization of three Schiff base compounds, namely N-(2-hydroxybenzylidene)-m-chloroaniline (1), N-(2-hydroxybenzylidene)-m-nitroaniline (2), and N-(2-hydroxybenzylidene)-m-methoxyaniline (3). Comprehensive spectroscopic analyses involving FT-IR, H1NMR, and UV-Vis were employed to elucidate their molecular structures. Theoretical calculations were conducted using the DFT/B3LYP method with the 6-311 + G (d, p) basis set, elucidating electronic transitions and providing comprehensive vibrational assignments. The study identifies key electronic features of these compounds by analyzing global chemical reactivity descriptors. Density functional theory (DFT) was employed to assess the ability of these compounds to scavenge free radicals, both in the gas phase and solvent environment, focusing on three primary mechanisms: hydrogen atom transfer (HAT), stepwise electron-transfer-proton transfer (ET-PT), and sequential proton-loss-electron transfer (SPLET). Additionally, the research explores drug-likeness properties and conducts molecular docking investigations against the ubiquinol cytochrome c reductase protein (UQCRB) to gain further insights into potential biological activities.

Nucleophilic transformation of 3-substituted-6,8-dimethylchromones with phenylhydrazine under various reaction conditions: Theoretical, spectroscopic characterization and in silico ADME studies

The chemical behavior of 3-substituted-6,8-dimethylchromones 1–3 was examined towards phenylhydrazine under various reaction conditions. Under different molar ratio, reaction of aldehyde 1 with phenylhydrazine produced hydrazone 4 and pyrazole 5. Depending on the solvent used, reacting carbonitrile 2 with phenylhydrazine produced a variety of products; through ring-opening and ring-closure mechanisms. Reaction of carboxamide 3 with phenylhydrazine, afforded chromeno[4,3-c]pyrazole derivative 8. Finally, boiling carboxamide 3 in KOH solution gave 4-hydroxy-6,8-dimethylcoumarin-3-carboxaldehyde (9). Molecular geometries were examined using density functional theory, (DFT/B3LYP) with 6–311 G(d,p) basis sets, to investigate the bond lengths of certain bonds. DFT was also used to compute some global reactivity descriptors including electronegativity (χ), chemical potential (μ), electrophilicity index (ω), softness (S) and hardness (η). Compound 4 is the softest, while compound 9 is more electrophilic and more electronegative. In addition, MEP surface maps were investigated to predict the chemical reactivity of the current molecules. The chemical shifts values of 1H and 13C NMR were assessed utilizing the GIAO method, and the results were compared with those obtained experimentally. The current compounds are appropriate for non-linear optical applications, according to their first order hyperpolarizability values which found 1.5–3 times greater than those of urea. SwissADME was used to explore the features of current compounds' absorption, delivery, metabolism, and excretion (ADME).

Synthesis, Characterization, and Photophysical Probing Interaction Studies on Azo‐Sulfonamides Acting as Potent Anti‐Tubercular Agents

AbstractBy utilizing the sulfamethizole component via the diazo‐coupling approach by electrophilic substitution process, an unprecedented series of four mono‐azo sulfonamide molecules were synthesized in good yield. Spectroscopic investigation unambiguously confirmed the structures of the newly synthesized mono‐azo sulfonamide derivatives, including FT‐IR, NMR (1H and 13C), HRMS, Uv‐Vis, and Photoluminescence (PL). In a variety of organic solvents, the 3‐diethylaminophenol coupled azo‐sulfonamide T3 showed a maximum bathochromic shift of λmax in the range 462–479 nm and in the region of 88–142 nm, a derivative of 2‐hydroxy‐1,4‐naphthoquinone T4 coupled azo colourant showed a significant Stokes shift. Conceptual density function theory was also used to build a new family of high energy density energetic mono‐azo sulfonamides. Frontier molecular orbitals (HOMO‐LUMO) and global reactivity descriptors were identified to analyze how molecules interact with one another. Further, the potency of the anti‐tubercular activity of the colorants was examined with the standards such as Isoniazid, Ethambutol, Pyrazinamide, Rifampicin, and Streptomycin. The results indicated that‐ Lawsone pigment (2‐hydroxy‐1,4‐naphthoquinone) incorporated azo molecule T4 displayed the sensitivity at 3.12 μg/mL compared with other the three mono‐azo molecules.

Theoretical Evaluation of the Properties of Nitrogen-Doped C24 Fullerenes and Their Interactions with Two Adamantane-Derived Antivirals

The replacement of carbon with a heteroatom within the structure of a fullerene gives the possibility of obtaining compounds with adjustable properties. The influence of aza-substitution on C24 fullerenes was investigated and a comparison of HF and DFT calculations was performed. Various substitution patterns were proposed and the characterization of C22N2 and C20N4 structures was performed. Global reactivity descriptors like chemical potential, hardness, HOMO–LUMO gap and singlet–triplet gap were computed. Aromaticity descriptors like delocalization indices and NICS(0) index were employed for the characterization of each six-membered ring of the studied fullerenes. The possible use of aza-fullerenes as drug delivery systems for two adamantane-derived antivirals was evaluated through molecular docking studies. The best results were obtained for the fullerenes with a pronounced hydrophobic character, the favored configuration of the antiviral drugs being the one oriented toward the side consisting of carbon atoms of the fullerenes.