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The current study focuses on the combined experimental and theoretical FT-IR and FT-Raman spectra of 1-carboxy-4-ethoxybenzene (1C4EB), to obtain vibrational frequencies and optimal geometrical parameters by HF and DFT. For 1C4EB, the kind of intramolecular interactions and their stabilization were performed by Natural Bond Orbital analysis. The Nonlinear optical p properties and the conclusive evidence for ICT were also analyzed. The electronic energies and absorption spectra in different mediums were determined. Furthermore, Mulliken charges distribution, molecular electrostatic potential maps, the condensed Fukui function and thermodynamic parameters were calculated. The topological properties and IRI were analyzed with the Multiwfn program. In molecular docking, target proteins 4ULE and 2EEP were used to investigate sugar phosphatase and Prolyl aminopeptidase inhibitor properties. The least binding energy -6.7 kcal/mol is observed for the selected protein 4ULE. The molecular dynamics of the complex between the proteins 4ULE and 2EEP – ligand, binding free energies also calculated by the Poisson-Boltzmann surface area method.

The FT-IR and FT-Raman spectra was recorded within the range of 4000 -500 cm−1 and compared with the theoretically obtained spectra. The 13C and 1H NMR chemical shifts have been calculated using the GIAO technique, and the output has been compared with experimental data. The optimized molecular structure and stability analysis of the aztreonam compound have been calculated by the DFT/B3LYP/6–311++G(d,p) level of theory. The molecular electrostatic potential, chemical descriptors, and HOMO-LUMO energies were also calculated. The in silico pharmacological evaluation shows that the title molecule exhibit drug-likeness, and ADMET properties. The ADMET results also indicate that the molecule can be employed in anti-tuberculosis treatments to discover new drugs. Furthermore, molecular docking analyses have been performed to understand the most active binding sites of the compound with the target protein. The molecules are docked with the PknB protein, with free binding energy values of Aztreonam is -7.25 and Mitoxantrone is -6.79 kcal/mol.

The primary objective of research to reveals the effective drug treatment for corona virus disease (COVID-19). The current study on alpha-cyano-4-hydroxycinnamic acid (ACHC), the theoretical predictions were done by using Gaussian 09 W software on the basis of DFT/ TDFT/B3LYP methods with basis set of 6–311++G (d, p). The vibrational wavenumbers were obtained from the observed FT-IR and FT-Raman spectra and these vibrations were assigned on the basis of their potential energy distribution (PED) contribution. 1H and 13C NMR chemical shift of the molecule were computed by using Gauge independent atomic orbital (GIAO) method. In UV-Visible analysis the electronic transition was predicted by Time-dependent self-consistent field (TD-SCF)/DFT method. NBO analysis was done to understand the possible the intermolecular interaction, electron transition within the donor and acceptor orbitals of the molecule. The HOMO and LUMO indicates the prominent charge transfer possibilities and its energy gap shows stability of the molecule. A molecular electrostatic potential (MEP) image shows the electrophilic and nucleophilic sites of the molecule. Molecular docking analysis was carried out against Agaricus bisporus tyrosinase (2Y9X) and severe acute respiratory syndrome corona virus 2 (6LZG).

In this present work, to investigate the physicochemical properties of the molecules, extensive quantum chemical calculations have been performed on 2-cyano-5-fluoropyridine (2C5FP) and 3-cyano-2-fluoropyridine (3C2FP). Infrared and Raman spectra analysis have been carried out to study the vibrational modes of the molecule. Based on density function theory (DFT) with 6–311 ++ G (d, p) basis set, was also used to compute the same modes. As a result of intramolecular interactions, charge transfer or delocalization of charge has been explained by natural bond orbital analysis. The NMR study was also carried out experimentally and theoretically. The nucleophilic and electrophilic sites were predicted by Molecular Electrostatic Potential surface (MEP). By using the same functional and basis set and GIAO method, theoretical predictions were made. The absorption wavelengths of title molecules have been studied both theoretically and experimentally using UV–visible analysis. The Mullikan population analysis and Natural atomic charges are used to calculate the net charges of the atoms in the molecules, and the calculated net charges are compared to the experimental chemical shift values. A molecular docking study revealed that the title molecules may have antidiabetic properties when bound to protein Glycogen Phosphorylase B Complexed Glucose.

The density functional theory with the Becke, 3-parameter, Lee–Yang–Parr (B3LYP) technique and the 6-311++G(d,p) basis set is used to optimize the compound 1-Phenyl- 1,3-butanedione (1P1 3B). The 1-phenyl-1,3-butanedione may be obtained in good yield by first preparing a triketone from acetylacetone and a halogenated benzoyl derivative in the presence of a metal halide and tertiary amine in an organic solvent, and then deacetylating the triketone in the presence of an acid. The geometric characteristics of the featured molecule are calculated, and the vibrational frequencies with potential energy distribution (PED) are determined and compared to experimental data. The time-dependent density-functional theory (TD-DFT) technique was used to compute the frontier Molecular Orbitals. Using the HOMO-LUMO energy values, further electronic properties for 1P1 3B were determined. The reactive sites were estimated using the Electron Localisation Function (ELF), and the Molecular Electrostatic Potential (MEP). As a direct consequence of this, the whole molecule's electrophilic and nucleophilic areas have been mapped out. Natural bond orbital (NBO) calculations were used to investigate the delocalization of electron density. The drug likeness features of 1P13B were investigated. The Ramachandran plot is used to study the stability of hydrolase and antibody proteins. The headline molecule is subjected to molecular docking research in order to better understand its biological activities, as well as the minimal binding energy and hydrogen bond interactions.

Isorhapontigenin (IRPG) drug emerges as promising efficient inhibitor for H1N1 and H3N2 subtypes which belong to influenza A virus; reported with IC50 value of 35.62 and 63.50 μM respectively. When experimental data are compared to the predicted geometrical parameters and vibrational assignments (FT-IR and FT-Raman), the findings indicated a strong correlation. The absorption bands of π→π∗ transitions are revealed through UV-Vis electronic properties; this confirms that the IRPG molecule shows strong bands. Through NBO and HOMO-LUMO analysis, the kinetic stability and chemical reactivity of the IRPG molecule were investigated. By using an MEP map, the IRPG's electrophilic and nucleophilic site selectivity was assessed. In a molecular docking investigation, the IRPG molecule shows a stronger inhibition constant and binding affinity for the H1N1 and H3N2 influenza virus. The IRPG molecule thus reveals good biological actions in nature and can be used as a potential therapeutic drug candidate for H1N1 and H3N2 virus A influenza.

The inducement of physical, chemical, structural and biological properties to entice of pharmaceutical property was analyzed by Vibrational spectroscopic, biological and theoretical tools. The structural arrangement for describing structure activity was investigated by injecting ligand groups in internal coordinate system by molecular tools (FT adopted IR, Raman, and NMR). Bond length and bond angle strain was pronounced much due to the chemical equivalent forces extension due to the injection of substitutional groups on base compound and thus non-Centro symmetry was processed. The molecular charge depletion profile was thoroughly studied to persuade protonic and electronic delocalization setup for arranging the drug potential. The chemi-equivalent potential exchange was monitored among different parts of the molecule for obtaining drug mechanism. The biological profile was keenly observed to look at the biological ambiance of the present molecule to fabricate advanced drug. The Lipinski five rule parameters; MV = 137.18, LogP = 0.27, HBD = 2, HBA = 2 and TPSA = 46.2 A2 showed the enhancement of additive drug quality. The exchange of oscillating chemical energy in the core and allied carbons of the base skeleton was keenly noted to find the prearranged chemical environment for successful drug mechanism. The non bonded transitions between Lewis acid and base of bonded molecular system were observed to determine the restoring potential to customize drug potential. The drug assistance for enantiomer characteristics of chirality sequence was displayed to expose the toxicity effect of the molecule. The active molecular bondings on different sites of molecule were measured by estimating polarizability and associated biological inhibition was validated.

The IUPAC name of curcumin is (1E, 6E)-1,7-Bis(4-hydroxy-3methoxyphenyl) hepta-1,6-e-3,5-dione (7B3M5D) and is characterized by spectroscopic profiling with FT-IR and FT-Raman spectra obtained both experimentally and theoretically. PED analysis was done for the confirmation of minimum energy obtained in the title compound. Optimized geometrical parameters are compared with experimental values obtained for 7B3M5D by utilizing B3LYP functional employing 6–311++G (d,p) level of theory. The HOMO-LUMO, MEP, and Fukui function analysis has been used to elucidate the information regarding charge transfer within the molecule. The stabilization energy and charge delocalization of the 7B3M5D were performed by NBO analysis. This article assesses that the title compound act as a potential inhibitor of the PI3K/AKT inhibitor through in silico studies, like molecular docking, molecular dynamics (MD), ADMET prediction and also this molecule obeys Lipinski's rule of five. 7B3M5D was docked effectively in the active site of PI3K/AKT inhibitor.

1-(Phenyl(piperidin-1-yl)methyl)naphthalene-2-ol was synthesized and characterized utilizing spectroscopic techniques (FT-IR, FT-Raman, UV–Visible, NMR, Mass and CHNS analysis). The synthesized compound chemical structure was optimized using the Density Functional Theory (DFT) B3LYP/6-311G (d,p) basis set. The computational studies including NMR chemical shift value, vibrational frequencies, natural bond orbital (NBO), frontier molecular orbital (FMO), molecular electrostatic potential (MEP), HOMO-LUMO, NLO, dipole moment, Mulliken charge analysis, thermal studies and potential energy surface (PES) analysis. Molecular docking studies were also carried out for Haemophilus influenza protein with target molecule using Autodock 4.2 versions and showed potential inhibitor activity against Haemophilus influenzae diseases.

The dibenzoxepines derivatives have found a broad application in biological and pharmaceutical fields as new prospective drugs. So, the molecule (3aS,12bS)-5-Chlor-2-methyl-2,3,3a,12b-tetrahydro-1H-dibenzo[2,3:6,7]oxepino[4,5-c]pyrrol has been characterized by DFT (Density Functional Theory) approach to predict the important properties of it. The minimum energy conformer has been found by PES (Potential Energy Surface) and then the structure is optimized. Further, the structure is characterized spectroscopically by FT-IR and FT-Raman techniques to know the functional group and chemically active atoms. The geometrical parameters, PED (Potential Energy Distribution) assignments have also been reported. The electronic properties of the title compound have been explained by UV-Vis and HOMO-LUMO analyses that describe the charge transfer between the atoms of the molecule. Molecular Electrostatic Potential (MEP), Electron Localization Function (ELF) and Localized Orbital Locator (LOL) have been depicted to know the chemically active regions. The electrophilic and nucleophilic regions have been shown by Fukui functions. The Non-Linear Optics (NLO) for non-linear optical effects and the Natural Bond Orbital (NBO) for charge delocalization were studied. To study the biological activity of the title compound, molecular docking has been performed which suggests that the title molecule may act as a membrane permeable inhibitor.

Brain tumors are one of the most dangerous, because the position of these are in the organ that governs all life processes. Moreover, a lot of brain tumor types were observed, but only one main diagnostic method was used - histopathology, for which preparation of sample was long. Consequently, a new, quicker diagnostic method is needed. In this paper, FT-Raman spectra of brain tissues were analyzed by Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), four different machine learning (ML) algorithms to show possibility of differentiating between glioblastoma G4 and meningiomas, as well as two different types of meningiomas (atypical and angiomatous). Obtained results showed that in meningiomas additional peak around 1503 cm -1 and higher level of amides was noticed in comparison with glioblastoma G4. In the case of meningiomas differentiation, in angiomatous meningiomas tissues lower level of lipids and polysaccharides were visible than in atypical meningiomas. Moreover, PCA analyses showed higher distinction between glioblastoma G4 and meningiomas in the FT-Raman range between 800 cm -1 and 1800 cm -1 and between two types of meningiomas in the range between 2700 cm -1 and 3000 cm -1 . Decision trees showed, that the most important peaks to differentiate glioblastoma and meningiomas were at 1151 cm -1 and 2836 cm -1 while for angiomatous and atypical meningiomas - 1514 cm -1 and 2875 cm -1 . Furthermore, the accuracy of obtained results for glioblastoma G4 and meningiomas was 88 %, while for meningiomas - 92 %. Consequently, obtained data showed possibility of using FT-Raman spectroscopy in diagnosis of different types of brain tumors., (Copyright © 2024. Published by Elsevier Inc.)

Non-linear optical (NLO) features of 3-[(4-Nitrophenyl Azo)]-9H-Carbazole-9-Ethanol (NPACE) chromophore were investigated by FT-IR, FT-Raman, and UV-visible spectra aided by Density Functional Theory (DFT) using the B3LYP/6-311++G(d,p) basis set of Gaussian 16 W package. It is observed from the DFT calculation that the slight increase in the endocyclic angle of C 13 -C 14 -C 15 and the reduction in exocyclic angle of N 40 -N 39 -C 14 and C 15 -C 14 -N 39 ascertained by experimental XRD values indicating the intramolecular charge-transfer interaction between the carbazole and nitrophenyl group through the diazo bridge. The vibrational contribution to the linear electro-optic effect is 15% of the total hyperpolarizability being calculated at B3LYP/6-311++G (d, p) for the NPACE molecule. It is also observed that the 8a, 19a, and 19b modes of the carbazole ring and the 8a, 8b, and 19b modes of the phenyl ring are found to be simultaneously and intensely active in IR and Raman spectra explaining the charge transfer interactions throughout the molecule. The low value of the HOMO- LUMO energy gap (2.5843 eV) and the deviation between the measured absorption wavelength (3.36 eV) from the computed (3.87 eV), both these facts substantiate the intramolecular charge transfer. The polarizability and first-order hyperpolarizability were calculated as 6.48 × 10 -24 and 3.8 × 10 -29 esu, respectively. The second harmonic generation (SHG) measurement experiment of NPACE was carried out using the powder method. The SHG efficiency is measured in comparison with the urea standard. The calculated torsional mode at 20 cm -1 is in excellent quantitative agreement with the experimentally determined terahertz absorption peak. The two-photon absorption coefficient of NPACE was estimated to be 0.9 × 10 -11 mW -1 , which is mainly due to the D-π-A type of molecular structure, and the optical limiting threshold for NPACE was estimated to be 1.52 × 10 13 Wm -2 enabling this material as a potential candidate for optical limiting applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

2,3:4,5-Bis-O-(1-methylethylidene)-beta-D- fructopyranose sulfamate otherwise called as Topiramate is a drug used for the treatment of alcohol dependence. Topiramate is a safe and consistently efficacious medication for treating alcohol dependence. The spectroscopic properties of Topiramate are investigated by Fourier Transform Infrared (FT-IR), Fourier Transform Raman (FT-Raman), Fourier Transform Nuclear magnetic Resonsnce(FT-NMR) andUltra Violet Visible (UV-visible) spectroscopic techniques. The FTIR, FT-Raman, FT-NMR and UV-visible spectra of Topiramate have been recorded and analyzed. Theoretical vibrational frequencies, geometric parameters, thermodynamic properties, Natural population analysis and Mulliken atomic charges of Topiramateare obtained by the Restricted Hartree-Fock (RHF) and density functional theory (DFT) using 6-31 + G(d,p) basis set. The calculated harmonic vibrational frequencies for Topiramate are compared with the experimental values of FTIR and FT-Raman spectra. The observed and the calculated frequencies are found to be in good agreement. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analysed using natural bond orbital (NBO) analysis. The first-order hyperpolarizability (β tot ) and other related properties such as dipole moment(µ), polarizability(α o )values of the investigated molecule are computed using HF and DFT/B3LYP with 6-31 + G(d,p) basis set. The calculated results also show that the Topiramate molecule may have microscopic nonlinear optical (NLO) behaviour., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of N-[(4-(trifluoromethyl)phenyl]pyrazine-2-carboxamide have been investigated experimentally and theoretically using Gaussian09 software package. Potential energy distribution of normal modes of vibrations was done using GAR2PED program. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. From the NBO analysis it is evident that the increased electron density at the nitrogen and carbon atoms leads to the elongation of their respective bond lengths and a lowering of their corresponding stretching wavenumbers. The calculated geometrical parameters are in agreement with that of similar derivatives. The calculated first hyperpolarizability is high and the calculated data suggest an extended π-electron delocalization over the pyrazine ring and carboxamide moiety which is responsible for the nonlinearity of the molecule.

The issue of effluent, especially organic colorants from several manufacturing units overlays an immense delinquent of the current epoch owing to its effect on oncogenic health hazards. Thus, Rare Earth Metal dysprosium (Dy) doped Zinc Ferrite (ZnFe 2 O 4 ) were as-synthesized by a facile co-precipitation technique as an effectual nano photocatalyst intended to the amputation of these noxious dyes. The structural, functional, optical, magnetic, and degradation properties of this RE (Dy 3+ ) doped ions were investigated using various characterizations, such as crystallite size (D) and several parameters (cation distribution, oxygen positional parameters, and bond length) were determined using XRD (X-ray diffraction) and it was found that as the dy 3+ ion concentration increases the speck size decreased and the grain size remained within nano regime, which intern affects the surface area. From BET analysis it was found that on increasing the doping concentration, the surface area increases which pave a substantial role in the photo-Fenton activity. By using FT-IR (Fourier-transform infrared spectroscopy) various functional parameters (elastic, interionic bonds, ion distribution, etc.) were determined. Raman spectra had no extra peak formation which is seen to have pure phase formation of the as-synthesized samples. HR-TEM (High-Resolution Transmission Electron Microscopy analysis were done to determine the nature of the sample, the as-synthesized magnetic samples exhibit a polycrystalline formation with cubical agglomeration. The magnetic property was very significant for x = 0.10 concentration. As-synthesized (Fe 0.9064 Zn 0.0936 ) [Fe 1.0936 Dy 0.1 Zn 0.8064 ] O 4 ) exhibits a momentous photo - Fenton activity against MB (Methylene blue), its removal efficiency was found to be 97.3% after 45 min. Also, this spinel ferrite acts as a magnetic recyclable catalyst even after 5 cycles with an insignificant lessening of elements and photo-Fenton activity., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The DFT studies of the 1-Amino-5-chloro-anthraquinone (ACAQ) molecule have been carried out with extensive and accurate investigations of detailed vibrational and spectroscopic investigations and validated by experimentally. The optimized molecular structure and harmonic resonance frequencies were computed based on DFT/B3LYP method with 6-311G++(d,p) basis set using the Gaussian 09 program. The experimental and calculated vibrational wavenumbers were assigned on the basis of PED calculations using VEDA 4.0 program. The 13 C NMR isotropic chemical shifts of the molecule were calculated using Gauge-Invariant-Atomic Orbital (GIAO) method in DMSO solution and compared with the experimental data. The absorption spectrum of the molecule was computed in liquid phase (ethanol), which exhibits л to л* electronic transition and compared with observed UV-Vis spectrum. Frontier molecular orbitals analysis shows the molecular reactivity and kinetic stability of the molecule. The Mulliken atomic charge distribution and molecular electrostatic potential surface analysis of the molecule validate the reactive site of the molecule. The natural bond orbital analysis proves the bioactivity of the molecule. Molecular docking analysis indicate that ACAQ molecule inhibits the action of c-Met Kinase protein, which is associated with the thyroid cancer. Hence, the present study pave the way for the development of novel drugs in the treatment of thyroid cancer., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

This paper proposes a ROC curve-based methodology to find optimal classification model parameters. ROC curves are implemented to set the optimal number of PCs to build a one-class SIMCA model and to set the threshold class value that optimizes both the sensitivity and specificity of the model. The authentication of the geographical origin of extra-virgin olive oils of Arbequina botanical variety is presented. The model was developed for samples from Les Garrigues, target class, Samples from Siurana were used as the non-target class. Samples were measured by FT-Raman with no pretreatment. PCA was used as exploratory technique. Spectra underwent pre-treatment and variables were selected based on their VIP score values. ROC curve and others already known criteria were applied to set the threshold class value. The results were better when the ROC curve was used, obtaining performance values higher than 82%, 75% and 77% for sensitivity, specificity and efficiency, respectively., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The experimental geometry (XRD), vibrational (IR and Raman), electronic (UV-visible) and NMR spectra of (S)-4-(4-Amino-benzyl)-oxazolidin-2-one (ABO) have been corroborated with the corresponding first principle calculated values at DFT using hybrid B3LYP exchange correlation functional invoking 6-311++g(d, p) basis set. The optimized geometrical parameters were found to be in satisfactory agreement with the experimental values obtained from the X-ray diffraction structural features of ABO. The scaled down computed vibrational frequencies with appropriate scaling factors were in good correspondence with the experimental observations. Room-temperature 1 H and 13 C nuclear magnetic resonance (NMR) studies were supported by advanced density functional theory calculations. The theoretical spectrograms of FT-IR, FT-Raman, 1 H NMR, 13 C NMR and UV of the title compound have been constructed and compared with experimental spectra and Hirshfeld surface analysis has also been made to study the intermolecular interactions. The electronic structure of the title compound has also been studied in terms of HOMO, LUMO and MESP diagrams., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The secondary metabolites produced by Fusarium can cause disease and death when consumed and produce biological responses even in the absence of the microorganism. The IL-6, TNF-α and TGF-β1 cytokines immune reactivity was associated with histopathological and physico-chemical changes in skin of immune competent rats after administration of Fusarium oxysporum crude extract. Rats were intradermally injected with 50 μl of 0.5 mg/ml crude extract and were euthanized at 3, 6, 12 and 24 h after injection. The inflammatory response was quantified by enzyme myeloperoxidase activity and by immunohistochemical method to detect the IL-6, TNF-α and TGF-β1. Physico-chemical analysis was performed using FT-Raman Spectroscopy. The inflammatory response was most intense at 6 and 12 h after crude extract administration and the most significant histopathological changes were observed in the dermis. Myeloperoxidase activity was intense from 3 to 24 h after injection. The immunostaining of pro-inflammatory cytokines IL-6 and TNF-α peaked at 6 h. Immunostaining for TGF-β1 was highest at 12 and 24 h. FT-Raman spectral analysis showed both, the most intense Fusarium interaction with the skin at 6 h, as revealed by the changes in the stretching of -CH bands (3100-2800 cm -1 ) in the dermis, and skin recovery trending after 12 h after crude extract injection. The results showed that secondary metabolites stimulated histopathologic changes and inflammatory responses even in the absence of the fungus, increasing myeloperoxidase activity and pro-inflammatory cytokine expression besides promoting physico-chemical changes., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A set of experimental and computational techniques have been applied for the understanding of fundamental spectroscopic and reactive properties of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron) compound. Experimental techniques employed in this study encompassed spectroscopic characterization via IR and Raman approaches, while optical properties were studied by measurements of UV/Vis spectra. The thermogravimetric analysis was also studied in order to analyze the stability of diuron. Aside from the determination of reactive properties, DFT calculations on isolated molecules were also used to thoroughly visualize and analyze spectroscopic properties such as IR and UV/Vis. MD simulations were used in order to understand interactions with water, while periodic DFT calculations were used in order to analyze band structure and density of states of the diuron crystal structure. Since the crystal structure of diuron is known, it was used in order to extract the relevant molecular pairs and investigate interactions between them by DFT and symmetry adapted perturbation theory approaches (SAPT)., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The spectroscopic (FT-IR, FT-Raman, NMR), electronic (UV--Vis.), structural and thermodynamical properties of an anti-inflammatory analgesic called Naproxen Sodium, (s)-6-methoxy-α-methyl-2-naphthaleneacetic acid sodium salt are submitted by using both experimental techniques and theoretical methods as quantum chemical calculations in this work. The equilibrium geometry and vibrational spectra are calculated by using DFT (B3LYP) with 6-311++G (d,p) basis set using GAUSSIAN 09. The vibrational wavenumbers are also corrected with scale factor to take better results for the calculated data. The HOMO-LUMO calculations are carried out on the title compound. The theoretical and experimental NMR peaks were found to be in good agreement. In addition, the detailed study on the Non-Bonding Orbitals, the excitation energies, AIM charges, condensed fukui calculations, thermodynamical properties, Localized Orbital Locator (LOL) and Electron Localization Function (ELF) are also performed. Furthermore, the study is extended to calculate the first order hyperpolarizability and to predict its NLO properties. The docking studies details helped on predicting the binding with different proteins., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Herein we describe the interaction of starch, urea, and melamine (C 3 N 6 H 6 ) in composite materials for use as controlled-release plant fertilizer. Slow-release fertilizers are important in minimizing nutrient losses due to run-off, leaching, and other factors. Urea is an effective plasticizer for starch and is an important nitrogen fertilizer throughout the world. Melamine also has high nitrogen content and could be combined with urea-starch composites to provide enhanced controlled-release fertilizer. This study reports the structural interaction and the performance gain of melamine addition to starch-urea composites. Composites were characterized by spectroscopic techniques (FT-Raman and 13 C NMR) detailing the interaction between melamine, urea, and starch. These interactions helped facilitate extrusion processing by lowering viscosity and processing temperatures suggesting an enhanced starch plasticizing effect of starch-urea-melamine composites. Further research into the co-plasticization of starch by urea and melamine could be exploited for improved controlled-release fertilizer products. Further research into the co-plasticization of starch by urea and melamine could be exploited for improved controlled-release fertilizer products., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Density functional theory is one of the most popular accepted computational quantum mechanical techniques used in the analysis of molecular structure and vibrational spectra. Experimental and theoretical investigations of the molecular structure, electronic and vibrational characteristics of 4-[2-(Dipropylamino) ethyl]-1,3-dihydro-2H-indol-2-one are presented in this work. The title compound was characterized using FT-IR, FT-Raman and UV-Vis spectroscopic techniques. The results were compared with the theoretical calculations obtained using DFT/B3LYP with 6-311++G(d,p) as basis sets and was found to be in good agreement. The complete optimization of the molecular geometry of the title compound was carried out. Further, the vibrational assignments and calculation of potential energy distribution (PED) were reported. NLO has emerged as a key factor in recent researches. Materials showing nonlinear optical properties form the basis of nonlinear optics and development of such materials plays an important role in the present scenario. The current work provides sufficient justification for the title compound to be selected as a good non-linear optical (NLO) candidate. The electronic properties were reported using TD-DFT approach. The HOMO (EHOMO = -5.96 eV), LUMO (ELUMO = -0.80 eV) energies, energy gap and electrophilicity (2.22) was calculated in order to understand the stability, reactivity and bioactivity of the compound under investigation. To comprehend the bonding interactions we have performed the total (TDOS), partial (PDOS) and overlap population or COOP (Crystal Orbital Overlap Population) density of states. The drug likeness values were analyzed to evaluate the potential of the title compound to be an active pharmaceutical component. As a positive proof the paper further explains the molecular docking studies of the said compound. In addition, the stereochemistry of the protein structure was checked using Ramachandran plot. The title compound is a directly acting dopamine D2 agonist. In order to establish relationship between molecular descriptors of compound and its biological activity, QSAR studies have been done within the framework of DFT for 10 dopamine agonist including the title compound. Hence, the research exploration provides requisite information pertaining to the geometry, stability, reactivity and bioactivity of the compound through spectroscopic and quantum chemical methods., (Copyright © 2019. Published by Elsevier B.V.)

Chalcone derivative of (2E)‑1‑(3‑bromo‑2‑thienyl)‑3‑(2,5‑dimethoxyphenyl) prop‑2‑en‑1‑one (BTD) molecule has been deliberated for spectroscopic properties experimentally and theoretically. The title compound was characterized by FT-IR, FT-Raman and UV-Vis analyses. The structural activity and vibrational wavenumbers were calculated by a DFT method. The Natural Bond Orbital (NBO) analysis which reveals the hyper conjugative interactions of the present molecule has been performed. Meanwhile, the Chemical reactivity of Condensed Fukui function, MEP and HOMO-LUMO energies of the molecule were also analyzed. Furthermore, Multiwfn 3.3.9 program has been utilized to study MEP and the electron excitation analysis. Docking studies which play a significant role in determining the endothelial nitric oxide synthase inhibition activity of the present compound have also been carried out to predict the binding energy and inhibition constant of the title compound. In addition, drug resemblance parameters have also considered by QSAR study in which the comparison of chemical parameters of chalcone drugs of title molecule has been done., (Copyright © 2019. Published by Elsevier B.V.)

Cocrystal monohydrate of nitrofurantoin (NF) with melamine (MELA) has been studied as NF is an antibacterial drug used for the treatment of urinary tract infections. The structure of nitrofurantoin-melamine-monohydrate (NF-MELA-H 2 O) is characterized by FT-IR and FT-Raman spectroscopy. The energies and vibrational frequencies of the optimized structures calculated using quantum chemical calculations. Supported by normal coordinate analyses and potential energy distributions (PEDs), the complete vibrational assignments recommended for the observed fundamentals of cocrystal hydrate. With the aim of inclusion of all the H-bond interactions, dimer of NF-MELA-H 2 O has been studied as only two molecules of cocrystal hydrate are present in the unit cell. By the study of dimeric model consistent assignment of the FT-IR and FT-Raman spectrum obtained. H-bonds are of essential importance in an extensive range of molecular sciences. The vibrational analyses depict existence of H-bonding (O-H⋯N) between water O-H and pyridyl N atom of MELA in both monomer and dimer. To probe the strength and nature of H-bonding in monomer and dimer, topological parameters such as electron density (ρ BCP ), Laplacian of electron density (∇ 2 ρ BCP ), total electron energy density (H BCP ) and H-bond energy (E HB ) at bond critical points (BCP) are evaluated by quantum theory of atoms in molecules (QTAIM). Natural bond orbitals (NBOs) analyses are carried out to study especially the intra and intermolecular H-bonding and their second order stabilization energy (E (2) ). The value of HOMO-LUMO energy band gap for NF-MELA-H 2 O (monomer and dimer both) is less than NF, showing more chemical reactivity for NF-MELA-H 2 O. Chemical reactivity has been described with the assistance of electronic descriptors. Global electrophilicity index (ω = 7.3992 eV) shows that NF-MELA-H 2 O behaves as a strong electrophile than NF. The local reactivity descriptors analyses such as Fukui functions, local softnesses and electrophilicity indices performed to determine the reactive sites within NF-MELA-H 2 O. In MEP map of NF-MELA (monomer and dimer) electronegative regions are about NO 2 and C=O group of NF, although the electropositive regions are around NH 2 , N-H group and H 2 O molecule. Molar refractivity (MR) value of NF-MELA-H 2 O (monomer and dimer) lies within the range set by Lipinski's modified rules. This study could set as an example to study the H-bond interactions in pharmaceutical cocrystals., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The purpose of this article is to predict the molecular structure of the cocrystal of dipfluzine-benzoic acid (DIP-BEN) through computational approach (DFT calculations) and validate it using vibrational spectroscopic studies. The molecular structure of the DIP-BEN cocrystal has been predicted by forming models on the basis of the active sites available to form H-bonds between dipfluzine (DIP) and benzoic acid (BEN). Conformational study has been performed and potential energy surface scans are plotted around the flexible bonds of the cocrystal molecule and three stable conformers have been obtained. Quantum theory of atoms in molecules (QTAIM) explains that all the interactions are medium and partially covalent in nature. Natural bond orbital analysis of the second order perturbation theory of the Fock matrix suggests that interactions LP (2) O2 → σ*(O74H75) and LP (2) F1 → σ* (O89H90) are responsible for the stabilization of the molecule. The HOMO and LUMO energies and electronic charge transfer (ECT) confirms that charge flows from BEN to DIP. Global reactivity descriptor parameters suggest that DIP-BEN cocrystal is softer, thus more reactive in comparison to DIP. Local reactivity descriptor parameter is used to predict reactive sites of the cocrystal. The experimental and theoretical results support the formation of cocrystal through strong hydrogen bond (O89H90⋯F1 and O74H75⋯O2) interactions present in cocrystal., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The main objective of the study is to analyze the structural behaviour and fungicidal activity of clotrimazole by experimental and theoretical spectroscopic techniques. Its computational results are correlated with three triphenyl imidazole derivative compounds. The clotrimazole-water complexes formed by hydrogen bonding interactions are investigated at the B3LYP/6-311G(d,p) level. The distributions of the vibrational bands are carried out with the help of normal coordinate analysis (NCA). Hirshfeld surface analysis of clotrimazole is done and the obtained finger print plots reveal the interactions within the compound. The stability of the compounds in water has been investigated by using molecular dynamics simulation (MDS). Molecular docking is done on the compounds in comparison with the native ligand (Lanosterol 14α-demethylase) and standard drug (fluconazole) to study the hydrogen bond energy interaction. The antifungal activity of clotrimazole is analyzed by using two fungal pathogens., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The drug action of ester type local anesthetic (LA) procaine hydrochloride (PRC HCl) is activated by blocking Na + ion flow when it binds to the ion channel in the ligand gated sodium ion channel protein. Büchi's model, explains binding action of ester type LA drug with receptor in terms of charge transfer, dipole-dipole, hydrogen bonding and van der Waals interactions through lipophilic, ester and hydrophilic moieties. The present work investigates molecular structural and vibrational spectral features of para amino benzoate group, ester part and tertiary amino group respectively belonging to lipophilic, ester and hydrophilic moieties, accountable for the binding of drug to sodium channel. The electron transport mechanism through the ring responsible for structural deviation from benzenoid to quinonoid form and consequent dipolar nature of carbonyl group have been investigated, based on the analysis of XRD, DFT computed molecular structure, 8a ring mode and NBO charges. The characteristic UV absorption peaks and vibrational marker bands of LA drugs have been identified and the charge transfer interaction responsible for lipophilic binding has been investigated. The blocking of Na + in the ion channel has been probed using attractive and repulsive energy profile. The molecular polarizability has been computed to substantiate the correlation between the structure activity relationship of LA drug molecule and molecular polarizability. The low toxicity of PRC HCl was evaluated using in vitro cytotoxicity study, confirming it as a potential short acting local anesthetic., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This paper reports the synthesis of 5-(5-methyl-benzofuran-3-ylmethyl)-3H- [1, 3, 4] oxadiazole-2-thione (5MBOT) and characterization by FT-IR, FT-Raman, 1 H NMR, 13 C NMR and UV spectral studies. The density functional theory (DFT) calculations have been executed for the 5MBOT using B3LYP/6-31++G (d, p) basis set. The fundamental modes of the vibrations were designated by the potential energy distribution (PED), and the computed and experimental values support each other. The 1 H NMR and 13 C NMR chemical shifts of 5MBOT were estimated by gauge-including atomic orbitals (GIAO) method and compared with the experimental chemical shifts. The UV-Vis method used to study the visible absorption maxima (λ max ) by using Time-Dependent DFT. Further, the Mulliken population analysis (MPA), natural population analysis (NPA) charges, thermodynamic properties at different temperatures were presented. The calculated HOMO and LUMO energies show that charge transfer within the molecule. The natural bonds orbital (NBO) also computed. Optoelectronic properties have been carried out by combination of DFT calculations and molecular dynamics (MD) simulations, in order to assess the potential of this structure for applications in organic electronics. Further, the study encompassed calculations of reorganization energies for holes and electrons and charge transfer rates. DFT calculations have been also used in order to identify locations possibly sensitive towards the autoxidation mechanism, which correlates between bond dissociation energy for hydrogen abstraction and the mechanism. The MD simulations have been used to understand interaction of 5MBOT with water molecules. Molecular docking studies reveals the antifungal activity of 5MBOT may be due to hydrogen bonding and hydrophobic interactions with different antifungal proteins., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Febuxostat (FXT) is a urate-lowering drug and xanthine oxidase inhibitor which is used for the treatment of hyperuricemia and gout caused by increased levels of uric acid in the blood (hyperuricemia). The present study aims to provide deeper knowledge of the structural, vibrational spectroscopic and physiochemical properties of FXT based on monomeric and dimeric model with the aid of combination of experimental and computational methods. The conformational analysis of form Q has been done to predict the possible structure of unknown form A. Vibrational spectra of form A and Q has been compared to get an idea of hydrogen bonding interactions of form A. A computational study of FXT has been executed at different level (B3LYP, M06-2X, WB97XD) of theory and 6-31 G (d, p) basis set for dimeric model to elucidate the nature of intermolecular hydrogen bond. The red shift observed in the stretching modes of OH, CO groups and blue shift in stretching mode of CN group in experimental as well as in theoretical spectra explains the involvement of these groups in intermolecular hydrogen bonding. NBO analysis shows that change in electron density (ED) in the lone pair orbital to σ* antibonding orbital (LP1 (N39) → σ* (O3-H38)) with maximum value of E(2) energy confirms the presence of hydrogen bond (N39⋯H38-O3) leading to dimer formation. Study of topological parameters was executed for dimer using Bader's atoms in molecules (AIM) theory predicting the partially covalent nature of hydrogen bonds present in the molecule. The study of molecular electrostatic potential surface (MEPS) map ascertains that the CO, CN group are prone to electrophilic attack and OH group is active towards nucleophilic attack. The lower energy band gap and higher value of softness of dimeric model of FXT indicates its more reactivity, polarisability than monomeric model. The local reactivity descriptors predict the order of reactive sites towards electrophilic, nucleophilic and radical attack. An investigation made to determine the ligand protein interaction of FXT through docking with different molecular targets reveals the inhibitive as well as antibacterial nature of FXT., (Copyright © 2017. Published by Elsevier B.V.)

Photostability studies of drugs and drug products are an integral part of the product development process in the pharmaceutical industry. These studies are carried out to ensure quality, efficacy and safety of the formulated products during manufacture, storage and use. In this investigation, a novel spectroscopic approach has been adopted by employing the FTIR-ATR and UV/Visible techniques to detect the photochemical reactions of the drug Doxofylline, chemically designated as 7-(1, 3 dioxolane-2-yl methyl) theophylline, in its raw (pure) form. Significant changes were observed in terms of optical density of the absorption bands and a satisfactory analysis has been performed using ANOVA Statistics. It highlights the role of the photochemistry of drugs with respect to its spectral profiles and also explains photo physical processes. In addition; the drug compatibility study was also undertaken by using FTIR-ATR technique which indicated that there were no interactions occurring between the raw sample of the drug and the excipients used in the preparation of the pharmaceutical formulation. With this, UV-visible spectroscopic method was validated for the quantitative estimation of Doxofylline in pharmaceutical dosage forms and was performed with λ max at 274nm. Calibration curves were linear between the concentration range 10-50μg/ml. The various parameters such as linearity, precision, accuracy, recovery and specificity were studied according to ICH guidelines (Ahmed et al., 2016; Jain et al., 2011; ICH, 1996)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study aimed to evaluate the potential of FT-Raman spectroscopy in the prediction of the chemical composition of Lavandula spp. monofloral honey. Partial Least Squares (PLS) regression models were performed for the quantitative estimation and the results were correlated with those obtained using reference methods. Good calibration models were obtained for electrical conductivity, ash, total acidity, pH, reducing sugars, hydroxymethylfurfural (HMF), proline, diastase index, apparent sucrose, total flavonoids content and total phenol content. On the other hand, the model was less accurate for pH determination. The calibration models had high r 2 (ranging between 92.8% and 99.9%), high residual prediction deviation - RPD (ranging between 4.2 and 26.8) and low root mean square errors. These results confirm the hypothesis that FT-Raman is a useful technique for the quality control and chemical properties' evaluation of Lavandula spp honey. Its application may allow improving the efficiency, speed and cost of the current laboratory analysis., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Quantum chemical techniques such as density functional theory (DFT) have become a powerful tool in the investigation of the molecular structure and vibrational spectrum and are finding increasing use in application related to biological systems. The Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) techniques are employed to characterize the title compound. The vibrational frequencies were obtained by DFT/B3LYP calculations with 6-31G(d,p) and 6-311++G(d,p) as basis sets. The geometry of the title compound was optimized. The vibrational assignments and the calculation of Potential Energy Distribution (PED) were carried out using the Vibrational Energy Distribution Analysis (VEDA) software. Molecular electrostatic potential was calculated for the title compound to predict the reactive sites for electrophilic and nucleophilic attack. In addition, the first-order hyperpolarizability, HOMO and LUMO energies, Fukui function and NBO were computed. The thermodynamic properties of the title compound were calculated at different temperatures, revealing the correlations between heat capacity (C), entropy (S) and enthalpy changes (H) with temperatures. Molecular docking studies were also conducted as part of this study. The paper further explains the experimental results which are in line with the theoretical calculations and provide optimistic evidence through molecular docking that the title compound can act as a good antidepressant. It also provides sufficient justification for the title compound to be selected as a good candidate for further studies related to NLO properties., (Copyright © 2017. Published by Elsevier B.V.)

Carbohydrates are widespread and naturally occurring compounds, and essential constituents for living organisms. They are quite often reported when biological systems are studied and their role is discussed. However surprisingly, up till now there is no database collecting vibrational spectra of carbohydrates and their assignment, as has been done already for other biomolecules. So, this paper serves as a comprehensive review, where for selected 14 carbohydrates in the solid state both FT-Raman and ATR FT-IR spectra were collected and assigned. Carbohydrates can be divided into four chemical groups and in the same way is organized this review. First, the smallest molecules are discussed, i.e. monosaccharides (d-(-)-ribose, 2-deoxy-d-ribose, l-(-)-arabinose, d-(+)-xylose, d-(+)-glucose, d-(+)-galactose and d-(-)-fructose) and disaccharides (d-(+)-sucrose, d-(+)-maltose and d-(+)-lactose), and then more complex ones, i.e. trisaccharides (d-(+)-raffinose) and polysaccharides (amylopectin, amylose, glycogen). Both Raman and IR spectra were collected in the whole spectral range and discussed looking at the specific regions, i.e. region V (3600-3050cm -1 ), IV (3050-2800cm -1 ) and II (1200-800cm -1 ) assigned to the stretching vibrations of the OH, CH/CH 2 and C-O/C-C groups, respectively, and region III (1500-1200cm -1 ) and I (800-100cm -1 ) dominated by deformational modes of the CH/CH 2 and CCO groups, respectively. In spite of the fact that vibrational spectra of saccharides are significantly less specific than spectra of other biomolecules (e.g. lipids or proteins), marker bands of the studied molecules can be identified and correlated with their structure., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Our previous investigation on high pressure supercritical carbon dioxide treatment of a bacterial α-amylase had revealed enhanced activity of the same. 1 H NMR analysis of the activity enhanced enzyme led the authors to hypothesize that the enhancement was possibly owing to alterations in the active site of the enzyme. In the present study, the changes in the active site of the treated enzyme was analysed by Fourier-transform Raman (FT-Raman) spectroscopy. The spectra obtained revealed shifting of bands in the active site of α-amylase indicating a nudging effect of the bonds in this region consequent to high pressure treatment. Also, shifts in bands in the OH stretching vibration of water were observed in the enzyme spectra. These variations in the spectra confirmed changes in the active site as well as in the water associated with the same that perhaps had a concerted effect on the increased activity of α-amylase., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Experimental and theoretical investigations on the molecular structure, electronic and vibrational characteristics of 2-Amino-3-bromo-5-nitropyridine are presented. The vibrational frequencies were obtained by DFT/B3LYP calculations employing 6-311++G (d, p) basis set. This was compared with experimental FT-IR and FT-Raman spectral data. Simulated FT-IR (4000-400cm -1 ) and FT-Raman spectra (4000-100cm -1 ) showed good agreement with the observed spectra. The molecular equilibrium geometry of the title compound was fully optimized. Quantum chemical calculations of the equilibrium geometry and the complete vibrational assignments of wavenumbers using potential energy distribution (PED) were calculated with scaled quantum mechanics. HOMO-LUMO energies, energy gap (ΔE), electronegativity (χ), chemical potential (μ), global hardness (η), softness (S) and the Fukui function were calculated for the title molecule. The title compound has a low softness value (0.239) and the calculated value of electrophilicity index (5.905) describes the biological activity. The stability and charge delocalization of the title molecule were studied by Natural Bond Orbital (NBO) analysis, Non-Linear Optical (NLO) behaviour in terms of first order hyperpolarizability, dipole moment and anisotropy of polarizability and Molecular Electrostatic Potential (MEP) were accounted. The computed values of μ, α and β for the title molecule are 1.851 Debye, 1.723×10 -23 esu and 7.428×10 -30 esu respectively. The high β value and non-zero value of μ indicate that the title compound might be a good candidate for NLO material. Thermodynamic properties of the title molecule were studied for different temperatures thereby revealing the correlations between heat capacity (C), entropy (S) and enthalpy changes (H) with temperatures. Docking studies of the title compound were scrutinized to predict the preferred binding orientation, affinity and activity of the given compound. The title compound was docked into the active site of the protein 5FCT which belongs to the class of proteins exhibiting the property as a Dihydrofolate synthase inhibitor. A minimum binding energy of -5.9kcal/mol and intermolecular energy of -6.5kcal/mol is seen in the interaction., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Methods to obtain pure proteins in large amounts are indispensible in protein research. We report here a large-scale/simultaneous isolation of taxon-specific crystallins (ɛ- and δ-crystallin) from the eye lenses of Mule duck. We also investigate the compositions, enzymatic activities, and structures of these purified taxon-specific proteins. A relatively mild method of ion-exchange chromatography was developed to fractionate ɛ-crystallin and δ-crystallin in large amount, ca. ∼6.60mg/g-lens and ∼41.0mg/g-lens, respectively. Both crystallins were identified by electrophoresis, HPLC, and MALDI-TOF-MS. ɛ-Crystallin, with native composition of M r 142kDa, consisted of two subunits of 35kDa and 36kDa, while δ-Crystallin, with native molecular mass of 200kDa, comprised single subunit of M r ∼50kDa. Both ɛ- and δ-crystallin were tetramers. The former showed lactate dehydrogenase (LDH) activity, while the latter appeared slightly active in an argininosuccinate lyase (ASL) assay. Raman spectroscopic results indicated that the secondary structures of ɛ- and δ-crystallin were predominantly α-helix as evidenced by the vibrational stretching of amide III over 1260cm -1 and amide I at 1255cm -1 , in greatly contrast to the anti-parallel β-sheet of α- and β-crystallin as demonstrated by amide III at 1238cm -1 and amide I at 1672cm -1 . The microenvironments of aromatic amino acids and the status of thiol groups also vary in different crystallins. The compositions, enzyme activities, and structures of the ɛ- and δ-crystalline of Mule duck are different from those of Muscovy duck (Cairina moschata) or Kaiya duck (Anas Platyrhynchos var. domestica), which reflect faithfully species specificity., (Copyright © 2017 Elsevier B.V. All rights reserved.)