Vibrational Assignments Research Articles

Experimental and theoretical investigation of structure activity relationship on L-Lysine Monohydrate for antioxidant efficacy

Comprehensive spectroscopic research has been undertaken to investigate the structural behaviour of the l-lysine monohydrate molecule. The spectral properties of the l-lysine monohydrate molecule in solid phase were examined using Fourier Transform Infrared (FTIR) and Fourier Transform Raman methods. The B3LYP/6–311++G (d, p) computations were used to optimize the structure of the molecule. To provide complete vibrational spectral assignments, vibration energy distribution analysis (VEDA) was used. The Natural bond orbital (NBO) analysis explains the stability and distinct forms of hydrogen bonds with in the molecule. The chemical stability of the molecule is predicted by Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis. Non-Covalent Interaction (NCI) analysis was done to identify weak interactions according to density of electron of the title compound. The fukui function identified the chemical reactivity sites. To predict its antioxidant efficacy, docking studies were done.

2-(allylthio)-5-(5-phenyl-1H-pyrazol-3-yl)-1,3,4-oxadiazole: Synthesis, single crystal XRD, spectroscopic characterization, antidiabetic activity, DFT and ADMET studies

Here, we synthesized a new potent antidiabetic agent of pyrazolyl-1,3,4-oxadiazole derivative, named 2-(allylthio)-5-(5-phenyl-1H-pyrazol-3-yl)-1,3,4-oxadiazole (ATPO) and characterized it by FT-IR, UV–vis, 1H NMR, 13C NMR, HRMS-ESI, X-ray crystal structure and evaluated as dual inhibitor for α-amylase and α-glucosidase enzymes. Predicted FT-IR, UV–vis, 1H NMR, 13C NMR and UV–vis spectra and geometrical parameters for the optimized structures of ATPO in gas phase and ethanol solution by using B3LYP/6–311++G(d,p) method evidenced very good concordances with the corresponding experimental ones. Studies on atomic charges, molecular electrostatic potentials, stabilization energies and topological properties show that the phenyl, pyrazole and oxadiazole rings together with the allyl thiol moiety play a very important role in the stability, reactivity and behaviours of ATPO in both media. Thus, the compound is less stable in solution probably due to its higher reactivity in this medium and to its solvation energy (-75.89 kJ/mol). Complete vibrational assignments and the scaled force constants were performed for ATPO in both media. Also, ATPO exhibited outstanding α-glucosidase as well as α-amylase inhibitory potential with IC50 values of 35.47 ± 0.42 and 68.99 ± 1.08 µM, respectively, as compared to reference drug acarbose (IC50 (α-glucosidase) = 72.58 ± 0.68 µM, IC50 (α-amylase) = 115.6 ± 0.59 µM). In addition, ADMET studies were performed to investigate the possibility of using of the title compound as antidiabetic drug.

Experimental and computational study on the spectroscopic approach, chemical reactivity, hyperpolarizabilities and in-silico ligand-protein docking of 5-Chloro-2,4,6-trifluoropyrimidine

The 5-Chloro-2,4,6-trifluoropyrimidine (5CTFP) was chosen for extensive investigation of its theoretical and experimental vibrational assignments, structural discussion, and spectroscopic studies of Fourier-transform infrared (FT-IR), Fourier transform-Raman (FT-Raman), Ultraviolet–visible (UV–vis), and Nuclear magnetic resonance (NMR) by Hartree-Fock (HF) functional with 6-311+G(2d,p) basis set. The spectrum of detailed vibrational interpretation was to be provided by the MOLVIB software. Bonding orbitals participate in all stages of NBO analysis as donors and acceptors, which stabilises molecules through intermolecular charge transfer. Molecular docking research was used to foreseen the binding interactions of 5CTFP derivative with the estrogen receptor 3WZD. Auto-dock software was used to conduct receptor-ligand docking investigation. According to the molecular docking results, the highest mean negative binding affinity (−5.639 kcal/mol) was exhibited by the current chemical. Based on five-point rule of Lipinski, drug similarity was determined, and the ADMET variables were also predicted.

Synthesis, crystal growth, optical, thermal, electrical and theoretical investigation on 1,2,3- benzotriazole 2-chloro 4-nitrobenzoic acid (BCNB) single crystal for nonlinear optical (NLO) applications

The 1,2,3-benzotriazole 2-chloro-4-nitrobenzoic acid (BCNB) single crystal was successfully grown by the slow evaporation solution technique (SEST) and using methanol as the solvent for nonlinear optical applications. The crystal system and space group of the BCNB single crystal were identified by single crystal X-ray diffraction (SXRD) analysis. The BCNB crystal was subjected to powder X-ray diffraction (PXRD) to endorse the crystalline quality of the material. The UV–Visible-NIR study exposes the transparency and cut-off wavelength of the BCNB crystal. The chemical environment of carbon and hydrogen in the proposed structure of BCNB crystal was confirmed by FT-NMR studies. The vibrational assignments and their functional groups were identified from the FT-IR and FT-Raman analysis. The thermal properties like thermal stability point, melting point, and decomposing point were examined by Thermogravimetry/Differential thermal analysis (TG-DTA). The third order NLO behaviour of BCNB crystal was investigated by the Z-scan technique. The negative photoconductive nature of BCNB crystal was confirmed by photoconductivity analysis. The surface morphology of the grown crystal was examined by chemical etching analysis. The dielectric experiment (constant & loss) was performed on BCNB crystal as a function of frequency at room temperature to measure electrical properties of the material. Density functional theory (DFT) calculations have been investigated by DFT/B3LYP/6–311++G (d,p) method. To understand the intermolecular interaction of crystal packing, the BCNB material was investigated by Hirshfeld surface analysis and it was concluded that the molecular H-H interactions are of higher value compared to other interactions of the total molecules. The Gaussian 09 W programme was used for the DFT calculations such as molecule structure optimization, natural bond orbital analysis (NBO) and HOMO-LUMO analysis. The HOMO and LUMO energy values are estimated as −7.3239 eV and −2.8958 eV respectively.

A methodical investigation on the growth and characterization of a third-order nonlinear optical novel co-crystal of 8-hydroxyquinolinium phthalate: X-ray, Hirshfeld surface, optical, mechanical, thermal and DFT analysis

A novel non-linear optical single crystal of 8-hydroxyquinolinium phthalate has been as-synthesised by a slow evaporation solution growth technique. Single-crystal X-ray diffraction analysis affirms that it belongs to a monoclinic crystal system. While UV–visible spectroscopy shows its optical transparency with a direct band gap of 2.80 eV, a photoluminescence study confirms a principal yellow emission at 370 nm excitation. Furthermore, the mechanical and thermal properties along with the functional groups’ study have also been laid out in this paper. Intermolecular interactions present in the crystal are ascertained from Hirshfeld surface and fingerprint plot studies. The Z-scan technique has reportedly affirmed third harmonics generation in the same. Theoretical calculations using DFT modelling further testify to the experimental observations thereby laying out the framework of the mentioned crystal in terms of its optimized geometry, molecular electrostatic potential, frontier molecular orbital, natural bond orbital and natural population analysis along with vibrational assignments and UV absorption analysis.

First Principle Study on Structural, Electronic, Vibrational Properties and Molecular Docking Study of Tyramine

First principle study of cyclic compound has a great interest because their products are very much useful in biological and clinical applications. In this work, Density functional theory (DFT) and Time dependent DFT calculations have been performed to study structural, electronic and vibrational properties of Tyramine (a neuromodulator) at B3LYP/3-21G level employing Gaussian 09 software. All the theoretical calculations were carried out to study the equilibrium geometries, vibrational spectra, molecular electrostatic potential (MEP), highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) and UV-Vis spectra of the title compound. Also, the molecular docking analysis of Tyramine against two different proteins (Trace amine-associated receptor 1 and Dopamine D2 receptor) was carried out using AutoDock Vina. The scaled values of calculated vibrational frequencies were used for vibrational assignments on the basis of the potential energy distribution (PED). The structure activity relation has been interpreted by mapping MEP and Time dependent DFT method has been adopted to elucidate electronic properties. Graphical representation of frontier molecular orbital for both gaseous and solvent phase provides valuable insight into the nature of reactivity, stability and some of the structural and physical properties of the title molecule. Also, the calculated HOMO and LUMO energy values show that the charge transfer occurs within the molecule. Further, the title molecule shows good potentiality for binding against Trace amine-associated receptor 1 (1TQN) with binding affinity -6 kcal/mol The binding site of the Tyramine is found to be amine (NH2) group.

Effect of Long-Range Corrections on Intermolecular Interactions and Vibrational Assignments of Ethylene Oxide Dimer. A Combined DFT and SQFF Study

Theoretical structural and vibrational study for the ethylene oxide dimer have been performed by using the experimental structure determined by X-ray diffraction, the vibrational spectra and, the functional hybrids B3LYP/6-311++G** and WB97XD/6-311++G** methods. Here, the effects of dispersion on intermolecular interactions and on complete assignments of infrared and Raman spectra of dimer have been performed combining the Pulay´s scaled quantum mechanical force field (SQMFF) methodology with those two levels of calculations in order to fit the theoretical wavenumbers values to the experimental ones. Calculations including long-range corrections have revealed similar optimized energy, volume and frequencies to calculated with the B3LYP/6-31G* method, lower correlations in the geometrical parameters, higher stabilization energy, higher values in the topological parameters and higher scaled force constants than the obtained at B3LYP/6-311++G** level. Natural bond order (NBO) and atoms in molecules theory (AIM) studies with both methods reveal two types of intermolecular interactions (C-O···H and C-O···O) in the ethylene oxide dimer in accordance with the bands observed in the experimental Raman spectrum at low temperatures and with the experimental structure determined at 100 K. The nature of those interactions and their topological properties were studied by using NBO and AIM calculations. The studied properties for the ethylene oxide dimer were analyzed and compared with those obtained for the monomer. Similar assignments of the vibrational modes for dimer were obtained using the three different methods.

Vibrational characterization of active drug to the treatment of chagas disease, benznidazole by using force fields and internal coordinates

Two experimental structures of benznidazole active drug used to the treatment of Chagas disease have been structurally characterized and its vibrational spectra completely assigned combining B3LYP/6-311++G** calculations with the experimental FT-IR and FT-Raman spectra and the SQMFF methodology. The most stable conformer of benznidazole found in the study of the potential energy surface is in agreement with that experimentally observed by X-ray diffraction at room temperature while the other one was observed with the heating up to 195 ºC. Both differs in the positions of CH2 groups of acetamide fragment. Their structural properties in gas phase and ethanol solution were computed by using natural bond orbital (NBO), atoms in molecules (AIM), Merz-Kollman (MK) charges, molecular electrostatic potentials (MEP) and frontier orbitals calculations by using the hybrid B3LYP method and the 6-31G* and 6-311++G** basis sets. Additional WB97XD/6-311++G** calculations show that the energy values optimized for the most stable species in both media present lower values than the obtained with the B3LYP/6-31G* method. The vibrational assignments for those two conformers in both media were obtained from their corresponding harmonic force fields together with the scaled force constants.

Molecular structure, spectral analysis and chemical activity of sabizabulin: A computational study

In this study, a detailed computational spectroscopic investigation of sabizabulin, a small molecule known as a tubulin inhibitor with potential antineoplastic, antiviral, and anti-inflammatory activities, has been presented. Our work utilizes Density Functional Theory (DFT) calculations to explore molecular optimization, thermodynamic characteristics, and the analysis of normal modes with vibrational assignments. We calculate essential properties such as standard zero-point vibrational energy, entropy, dipole moment, etc., based on data extracted from the optimized molecular structure. Additionally, we examine Mulliken charges and the Molecular Electrostatic Potential (MEP) plot to comprehend the electronic distribution and chemical activity of sabizabulin. Our findings provide valuable insights into the spectroscopic properties of sabizabulin, highlighting its potential therapeutic applications. Our work aims to explore future research directions that could expand the understanding of sabizabulin's actions and enhance its applicability in medical treatments.

Synthesis, solvation effects, spectroscopic, chemical reactivity, topological analysis and biological evaluation of 4-chloro-N-(2, 6-dichlorobenzylidene) benzohydrazide

Being of the benzohyrazide derivatives, the molecule in consideration is quite significant in the pharmaceutical industry. In the present article, a novel compound has been synthesized and compared between the theoretical and experimental characterization such as FT-IR, UV–Vis and NMR techniques were employed. The quantum simulation studies (DFT) have been discussed for a higher basis set as B3LYP/6–311++G(d,p). Molecular vibrational assignments, chemical and electronic characteristics of 4-chloro-N -(2,6-dichlorobenzylidene) benzohydrazide (4CNB) were performed. The potential energy surface, geometrical optimization, wave numbers, and electronic structure stability were calculated by density function theory (DFT) through a higher basis set. The spectral characterizations of the molecule have been correlated with the observed spectrum. The chemical property of frontier orbital theory (FMO’s) and electron-hole excitation analysis (D-index, Δr index,t index and excited states) for the different solvents such as DMSO, Chloroform, water and methanol were analysed. The DOS and orbital overlap functions were investigated. The stability of the structure, electrophilic and nucleophilic attacks for the different solvents, intra molecular analysis through NBO,molecular electrostatic potential(MEP) and local descriptors such as Fukui function (f+, f-, f0), topological analyses were performed and discussed. Molecular docking studies were performed by Auto-dock software to establish the information about the interactions between the antifungal and antibacterial inhibitor and lest binding energy is observed for Candida glabrata (−7.50 kcal/mol) protein.

Sulfation of agarose with ammonium sulfamate: A combined experimental and theoretical study

Agarose sulfates are bioactive modified polysaccharides important for application. To obtain the bioactive agarose derivatives and expand the range of their potential use, the modification with some functional groups is needed. Agarose sulfates exhibit the anticoagulant, hypolipidemic, and other-type bioactivity. In this study, different methods for preparation of agarose sulfates using nontoxic ammonium sulfamate are investigated. Several activators and catalysts of the process of sulfation with ammonium sulfamate are examined. It is shown that urea does not significantly activate ammonium sulfamate in the sulfation reaction, while potassium permanganate ensures a sulfur content of up to 13.2 wt% in the synthesized agarose sulfate. When Lewis acids (titanium and aluminum oxides) are used, the sulfur content in agarose sulfates can only reach 7.3 wt%. The catalysts with the Brønsted acid sites used in the synthesis of sulfated agarose can provide sulfur contents of up to 14.6 wt% in it. The incorporation of a sulfate group into the agarose molecule has been confirmed by elemental analysis and Fourier-transform infrared spectroscopy: the absorption bands at 1249 cm‒1 have been observed in the spectra. The X-ray diffraction and atomic force microscopy studies have revealed no ammonium sulfamate inclusions. According to the X-ray diffraction patterns, sulfation of agarose enhances its X-ray amorphism. It has been established from the atomic force microscopy images that the incorporation of a sulfate group into the agarose molecule changes the size of particles on the film surface from 42 to 80 nm. The theoretical examination of initial and sulfated agarose has been carried out within the density functional theory. The molecular geometry, vibration assignments, HOMO‒LUMO, molecular electrostatic potential maps, and electronic properties of the substances have been established by the quantum-chemical calculations in the framework of the density functional theory.

Experimental, computational investigations and biological evaluation on 1-(3-acetamidophenyl)-5-mercaptotetrazole-cytotoxicity MTT assay

The current research is Experimental, Computational investigations and biological evaluation on 1-(3-Acetamidophenyl)-5-mercaptotetrazole which is a tetrazole derivative. Tetrazole moiety has wide spectrum of pharmaceutical applications. Density Functional Theory is employed for theoretical analysis and optimized structure, molecular geometry was obtained. Vibrational assignments and PED values were calculated. Experimentally and theoretically FT-IR, FT-Raman studies were carried out. Topology studies ELF, LOL and RDG were done on the title compound. UV analysis was done and peaks were obtained by both experimentally and theoretically with different solvents. HOMO LUMO energies and energy gap were also identified. MEP, NLO and Natural Bonding Orbital calculations were performed on title compound. Drug likeness properties and Ramachandran plot were identified. Finally, Molecular docking against anti-convulsant targets were performed using autodock tools and visualized with Discovery studio software. Theoretical results are compared with experimental results, which is in good agreement. Cytotoxicity assay studies were done on title compound. Results reveals that this compound is nontoxic and can be used as a anti – convulsant.

Shedding light into the biological activity of aminopterin, via molecular structural, docking, and molecular dynamics analyses

In this study, the structural and anticancer properties of aminopterin, as well as its antiviral characteristics, were elucidated. The preferred conformations of the title molecule were investigated with semiempirical AM1 method, and the obtained the lowest energy conformer was then optimized by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational frequencies of the optimized structure were calculated by the same level of theory and were compared with the experimental values. The vibrational assignments were performed based on the computed potential energy distribution (PED) of the vibrational modes. The molecular electrostatic potential (MEP) and frontier molecular orbitals (HOMO, LUMO) analyses were carried out for the optimized structure and the chemical reactivity has been scrutinized. To enlighten the biological activity of aminopterin as anticancer and anti-COVID-19 agents, aminopterin was docked into DNA, αIIBβ3 and α5β1integrins, human dihydrofolate reductase, main protease (Mpro) of SARS-CoV-2 and SARS-CoV-2/ACE2 complex receptor. The binding mechanisms of aminopterin with the receptors were clarified. The molecular docking results revealed the strong interaction of the aminopterin with DNA (−8.2 kcal/mol), αIIBβ3 and α5β1 integrins (−9.0 and −10.8 kcal/mol, respectively), human dihydrofolate reductase (−9.7 kcal/mol), Mpro of SARS-CoV-2 (−6.7 kcal/mol), and SARS-CoV-2/ACE2 complex receptor (−8.1 kcal/mol). Moreover, after molecular docking calculations, top-scoring ligand-receptor complexes of the aminopterin with SARS-CoV-2 enzymes (6M03 and 6M0J) were subjected to 50 ns all-atom MD simulations to investigate the ligand-receptor interactions in more detail, and to determine the binding free energies accurately. The predicted results indicate that the aminopterin may significantly inhibit SARS-CoV-2 infection. Thus, in this study, as both anticancer and anti-COVID-19 agents, the versatility of the biological activity of aminopterin was shown. Communicated by Ramaswamy H. Sarma

Synthesis, crystal structure, static and dynamic properties, molecular structure, reactive sites, wavefunction and molecular docking of 1-(3-((4-(diethylamino)-2-hydroxybenzylidene)amino)phenyl)ethan-1-one

The Schiff base compound1-(3-((4-(diethylamino)-2-hydroxybenzylidene)amino)phenyl)ethan-1-one (34D2HA) has been synthesized and characterized by FT-IR, XRD techniques. The title compound was optimized. From the calculated perspective, the title compound's Natural bond orbital, Molecular Electrostatic Potential, Electron Localization Function, Localized-Orbital Locator, Frontier Molecular Orbital, Mulliken charges and Fukui function properties were also examined. The vibrational analysis of 34D2HA were investigated by means of computational calculations. The intensity of vibrational bands and the fundamental frequencies were evaluated by the standard B3LYP method on the basis set of 6–311G(d,p) combination with diffusion function + + are done by density functional theory (DFT). In addition to PED, VEDA was utilized to predict vibrational assignment. The absorptions were analyzed theoretically using UV–Vis spectra with different solvents. The experimental and computed bond parameters exhibit a strong agreement. The infrared frequency calculations lead overall agreement with observed spectral patterns. Beside, ADME studies have been carried out and this compound satisfies with Lipinski's rule of five. The results of protein- ligand docking using the Auto Dock method with various proteins suggest that the molecule has pharmaceutical properties against receptors.

Synthesis, functional group analysis (experimental and theoretical), solvent –Solute interactions, structural insights of (E)-3-(4-chloro-3-(trifluoromethyl) phenyl) imino) indolin-2-one–In-vitro Antimicrobial activity

(E)-3-(4-chloro-3-(trifluoromethyl) phenyl) imino) indolin-2-one (4CTFI) has been synthesised and its structural features have been investigated by spectroscopic (FT-IR, FT-Raman, NMR and UV–vis) techniques. 4CTFI was optimized in gas phase, PA (polar aprotic), PP (polar protic) and NP (nonpolar) solvent phases using WB97XD/6-311++G(d,p) method. Vibrational assignments pertaining to different modes of vibration with potential energy distribution (PED) have been augmented by normal coordinate analysis (NCA). Using natural bond orbital (NBO) analysis, the compound's electronic stability as a consequence of hyper conjugative couplings and charge delocalization has been assessed. The Fukui functions and Molecular Electrostatic Potential (MEP) surface have been utilized to provide information about the nucleophilic and electrophilic locations for the aforesaid phases. The frontier molecular orbital (FMO) energy gap probably indicates a compound's strong chemical reactivity and enables eventual charge transfer inside the molecule. Furthermore, electron-hole distributions for four excited states and topological studies have been discussed. Moreover, this chemical adheres to Lipinski's decree, which implies that, in concept, consuming an oral intake will not be troublesome. ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) attributes have been investigated to evaluate drug discovery initiatives of our synthetic molecule. Docking of 4CTFI with antimicrobial proteins have been performed and the minimum binding energy of -6.52 kcal/mol was obtained for 4WAS protein. Macromolecule flexibility and stability on protein-ligand interactions have been effectively studied using the molecular dynamics simulation. Tests of in-vitro antimicrobial efficacy have been performed on microbial strains.

Anti Microbial Activity, Vibrational, Electronic and Topology Analysis of 3, 4, 5-Trimethoxybenzaldehyde

The density functional theory (DFT) approach has become one of the most gainful means to scrutinize the molecular structure and vibrational spectra are finding well-known use in the applications related to biological systems. The experimental and theoretical on the molecular structure, electronic, and characteristics of 3, 4, 5-Trimethoxybenzaldehyde (TMB) are reported. The structure of the molecule was optimized and structural characteristics were determined by DFT using the wb97xd method with 6-311 G++ (d, p) basis sets. The vibrational assignments were made on the basis of potential energy distribution. A good consistency between the observed and calculated spectra was achieved. The intramolecular charge transfer and second-order perturbation theory of Fock Matrix in Natural bond orbital analysis by means NBO analysis. It shows the electronic stability of the compound arising from hyper conjugative interactions and charge delocalization of that molecule. Besides, the HOMO-LUMO, MEP, and Fukui were performed. In this review, the present benzaldehyde derivatives for skirmishing against bacteria strain Escherichia coli and fungi strain Candida Sp. Spectral and quantum chemical calculations are also discussed.

Synthesis, spectroscopic investigations, topological non-covalent interactions, chemical reactivity, molecular docking and molecular dynamic simulation on piperazine succinate - A potential antimicrobial compound

Piperazine Succinate (PZSN) has been synthesized and extensively analyzed using various spectroscopic techniques, including FT-IR, FT-Raman and NMR spectra. In optimizing geometry, a comparison between the bond lengths of C2-H25 in PZSN (1.0999 Å) and SN (1.0938 Å) reveals an increase of 0.0061 Å in the C21-H25 bond length for PZSN. This elongation can be attributed to the significant C21-H25‧‧‧N2 intermolecular hydrogen bonding interaction. Natural bond orbital analysis of the molecule indicates a significant charge transfer between LP(1) N2 → σ* (C21-H25) leads to a substantial stabilization energy of 6.73 kcal/mol, providing strong evidence for the presence of intermolecular hydrogen bonding interactions. The strong band observed in the IR spectrum at 3510 cm−1, assigned to N2-H16 stretching mode, which clearly supports the formation of a hydrogen bond between succinate C=O and piperazine NH group. The complete vibrational assignments and the force constants has been reported for PZSN by using B3LYP/6–311++G** method. Molecular parameters, such as Frontier Molecular Orbital (FMO) energies, Fukui functions and Molecular Electrostatic Potential (MEP), have been calculated to gain insights into the stability and reactivity of the molecule. According to the QTAIM analysis, the presence of a strong non-bonded interaction is supported by the largest interaction energy observed at the C21-H25‧‧‧N2 bond critical point (BCP), which is 3.42 kcal/mol. Furthermore, Reduced Density Gradient (RDG) and Independent Gradient Model (IGM) approaches have been performed to disclose the attractive contacts like hydrogen bonds, repulsive and van der Waals interconnections. The molecule's drug-likeness has been assessed using Lipinski's rule and ADMET contour analysis indicated its potential for pharmaceutical applications. Molecular docking modeling have been conducted on antimicrobial proteins to explore the structure-activity relationship and antimicrobial testing confirmed the molecule's efficacy against microbial infections. Molecular dynamic simulations have been utilized to examine the stability of protein-ligand complex.

Molecular docking, QTAIM analysis, UV-Vis spectra, vibrational analysis, and electronic properties of Lantadenes C and D — A complete comparative study

We have done geometry optimization of two conformers of Lantadene series C and D. The fundamental vibrational frequencies with intensity have been done by using B3LYP/6-311G (d, p) method. The complete vibrational assignments of wavenumbers are made on the basis of potential energy distribution (PED). The nonbonding interactions in Lantadenes C and D are calculated by using the same level theory at the bond critical point (BCP). The calculated topological parameters at BCP are utilized to determine the nature and strength of interactions. We have also computed HOMO–LUMO gap and plotted frontier orbital HOMO–LUMO surfaces, molecular electrostatic potential surfaces to explain the reactive nature of Lantadenes C and D. The electronic transition spectra UV–Vis spectra of Lantadenes C and D are calculated by using TDDFT theory. The values of hyperpolarizability show a probable use of these compounds in electro-optical applications. The natural bonding orbital theory is utilized to calculate transition of electron from donor to acceptor which is very useful to describe nonbonding as well as bonding interactions. The calculated value of Log [Formula: see text] and Log [Formula: see text] for Lantadene C Lantadene D established its pharmaceutical behaviors. The biological activity of Lantadenes C and D is also calculated by using PASS online server for [Formula: see text]. The docking of Lantadene C Lantadene D is also performed by using Auto dock with predicted drug by Swiss dock online server.

Synthesis, Spectroscopic (FT‐IR, FT‐Raman), Electronic Properties and Molecular Docking Studies of 1‐(2, 6‐dibromo‐4‐methyl‐phenoxymethyl)‐benzo[f]chromen‐3‐one

AbstractHerein, 1‐(2,6‐dibromo‐4‐methyl‐phenoxymethyl)‐benzo[f]chromen‐3‐one (DBMPBC) is chosen to be thoroughly investigated in terms of structural, spectroscopic (FT‐IR, FT‐Raman) and molecular electronic properties based on density functional theory (DFT). The title molecule is synthesized by the reaction of 5,6‐benzo‐4‐bromomethylcoumarin with 2,6‐dibromo‐4‐methylphenol in presence of anhydrous potassium carbonate in dry acetone. All the computational studies for the selected structure are carried out at the theoretical level DFT/B3LYP/6‐311++G (d, p). The theoretically determined geometrical parameters from optimized structure and experimental values are compared to each other to confirm the structural properties of the molecule. The vibrational wavenumbers are studied by FT‐IR and FT‐Raman spectral techniques in both experimental and computational methods and compared to each other. The detailed vibrational assignments are assigned through potential energy distribution method by VEDA. The MEP surface analysis is carried out in order to identify the potential sites of electrophilic and nucleophilic attack. The Natural Bond Orbital (NBO) study significantly verified the existence of the intermolecular interactions in the molecule. The stability and reactivity properties of the molecule are estimated in terms of HOMO‐LUMO energies. Molecular docking investigations are carried out to simulate the inhibitory impact of the title molecule against the VEGFR2 (PDB: 2XIR) and PI3K (PDB: 2RDO) receptors for anti‐angiogenic therapy in the treatment of NSCLC. ADMET parameters and toxicity properties of the title molecule is conducted.

Label-Free identification of fentanyl analogues using surface-enhanced Raman scattering and machine learning algorithm

The identification and analysis of drug abuse is crucial for controlling and combating this global public health problem. In this regard, surface-enhanced Raman spectroscopy (SERS) is a highly sensitive detection technique that is fast, non-destructive, and widely used in various fields. In this study, Ag@Au nanowires (Ag@Au NWs) were synthesized using the seed growth method. The SERS performance of Ag@Au NWs was evaluated using R6G as a probe molecule, and the minimum detection concentration of R6G was found to be 10−9 M. Similarly, the minimum detection concentration of fentanyl was observed to be 10−7 M. Furthermore, the study also involved performing routine Raman detection on 10 fentanyl analogs that were structurally similar. Additionally, density functional theory (DFT) calculations were carried out to distinguish between these substances. The Raman spectra calculated by DFT provided vibrational frequencies and normal mode assignments for each species. By comparing normal Raman spectra, SERS and DFT calculated spectrogram data, we assigned characteristic peaks of 10 substances. Finally, principal component analysis was used to reduce the dimension of the data, and support vector machine were further used to classification of SERS spectral data of the above 10 substances, with an accuracy of 96.4%.