Yazar "Cinar M." seçeneğine göre listele
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Öğe A comparative study of selected disperse azo dye derivatives based on spectroscopic (FT-IR, NMR and UV-Vis) and nonlinear optical behaviors(2014) Cinar M.; Coruh A.; Karabacak M.In the present work, a combined experimental and quantum chemical study on ground state equilibrium structure, spectroscopic and nonlinear optical properties of selected disperse azo dye molecules are reported. The vibrational transitions were identified based on the recorded FT-IR spectra in the range of 4000-400 cm-1 for solid state, simulated IR spectra and total energy distribution (TED) of vibrational modes. The chemical shifts were determined from the results of observed 1H and 13C NMR spectra in chloroform and dimethylsulfoxide solution. The DFT/gauge-invariant atomic orbital (GIAO) methodology was applied to predict the magnetic properties. Electronic properties were carried out by UV-Vis spectroscopy and TD-DFT/CIS approach. The nonlinear optical (NLO) features were addressed theoretically. A detailed description of spectroscopic and NLO behaviors of studied disperse azo dyes was reported with the help of comparison of experimental measurements and theoretical calculations. © 2013 Elsevier B.V. All rights reserved.Öğe Conformational and spectroscopic behaviors of 2,4-xylyl isothiocyanate(Elsevier, 2015) Cinar M.; Karabacak M.; Chand S.; Shukla V.K.; Sinha L.; Prasad O.; Singh M.P.; Asiri A.M.This study aims to identify the conformational and spectroscopic characteristics of 2,4-xylyl isothiocyanate (C9H9NS) compound via experimental and computational methods. To accomplish this, density functional theory (DFT), with the B3LYP functional was used to determine ground state conformation, vibrational wavenumbers and also isotropic chemical shifts of the title molecule. Experimentally, vibrational features of the compound were evaluated by FT-IR and FT-Raman spectroscopic analysis in the solid phase. On the basis of these studies, the conformational and spectroscopic behaviors of 2,4-xylyl isothiocyanate were interpreted. The fundamental vibrational wavenumbers as well as their intensities were computed, and a good correlation between experimental and scaled calculated wavenumbers was observed. The polarizability, first hyperpolarizability and dipole moment values of 2,4-xylyl isothiocyanate were calculated at the same level of theory and basis set. The results show that 2,4-xylyl isothiocyanate molecule possesses nonlinear optical (NLO) behavior with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis. ©2015 Elsevier B.V. All rights reserved.Öğe Determination of conformational and spectroscopic features of ethyl trans-alfa-cyano-3-indole-acrylate compound: An experimental and quantum chemical study(2013) Cinar M.; Karabacak M.The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and non-linear optical properties of ethyl trans-alfa-cyano-3-indole-acrylate (C14H12N 2O2) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman in the range of 4000-400 cm-1 and 4000-10 cm -1, respectively. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The 1H, 13C and DEPT NMR spectra were recorded in DMSO solution, and gauge-invariant atomic orbitals (GIAO) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were recorded in the range of 200-800 nm in various solvents of different polarity (acetone, benzene, chlorobenzene, chloroform, DMSO, ethanol, methanol and toluene). Solvent effects were calculated using TD-DFT and CIS method. To investigate the non-linear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. © 2012 Elsevier B.V. All rights reserved.Öğe Determination of structural, spectrometric and nonlinear optical features of 2-(4-hydroxyphenylazo)benzoic acid by experimental techniques and quantum chemical calculations(2013) Cinar M.; Yildiz N.; Karabacak M.; Kurt M.The optimized geometrical structure, vibrational and electronic transitions, chemical shifts and nonlinear optical properties of 2-(4-hydroxyphenylazo)benzoic acid (HABA) compound were presented in this study. The ground state geometrical structure and vibrational wavenumbers were carried out by using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. The vibrational spectra of title compound were recorded in solid state with FT-IR and FT-Raman spectrometry in the range of 4000-400 cm -1 and 4000-10 cm -1 ; respectively. The fundamental assignments were done on the basis of the recorded spectra and total energy distribution (TED) of the vibrational modes. The 1 H and 13 C NMR spectra were recorded in deuterated DMSO solution, and gauge-invariant atomic orbitals (GIAOs) method was used to predict the isotropic chemical shifts. The UV-Vis absorption spectra of the compound were observed in the range of 200-800 nm in ethanol, methanol and water solvents. To investigate the nonlinear optical properties, the polarizability, anisotropy of polarizability and molecular first hyperpolarizability were computed. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. © 2012 Elsevier B.V. All rights reserved.Öğe Drug likeness scoring and quantitative structure anaplastic lymphoma kinase (ALK) inhibitors activities relationships of pyrazolone derivatives(American Scientific Publishers, 2018) Ouadah K.; Tchouar N.; Belaidi S.; Oukil O.; Cinar M.Series of twenty-four compounds was the field for applying multi-parameter optimization (MPO) methods and qualitative approximations of structural activity relationships in order to determine the role of various physico-chemical and quantum descriptors used in QSAR modeling as independent variables. Anaplastic lymphoma kinase (ALK) inhibitory activity was considered as a component in this study. In order to illustrate the quantitative relationships between the molecular descriptors and the activity of pyrazolone derivatives, we have applied a multiple linear regression (MLR) procedure. By adopting cross-validation with the leave-one-out method, we could estimate the predictability of models. Our results suggest a QSAR model based on the following descriptors: S, V, LogP, POL, Ref, HOMO, LUMO, E, , HBA, PSA and NRB, for the inhibitory activities against ALK. Results show high correlation between experimental and predicted activity values, indicating the validation and the good quality of the QSAR model. Copyright © 2018 American Scientific Publishers All rights reserved.Öğe An experimental and density functional study on conformational and spectroscopic analysis of 5-methoxyindole-2-carboxylic acid(Elsevier, 2015) Cinar M.; Karabacak M.; Asiri A.M.In this article, a brief conformational and spectroscopic characterization of 5-methoxyindole-2-carboxylic acid (5-MeOICA) via experimental techniques and applications of quantum chemical methods is presented. The conformational analysis of the studied molecule was determined theoretically using density functional computations for ground state, and compared with previously reported experimental findings. The vibrational transitions were examined by measured FT-IR and FT-Raman spectroscopic data, and also results obtained from B3LYP and CAM-B3LYP functionals in combination with 6-311++G(d,p) basis set. The recorded proton and carbon NMR spectra in DMSO solution were analyzed to obtain the exact conformation. Due to intermolecular hydrogen bondings, NMR calculations were performed for the dimeric form of 5-MeOICA and so chemical shifts of those protons were predicted more accurately. Finally, electronic properties of steady compound were identified by a comparative study of UV absorption spectra in ethanol and water solution and TD-DFT calculations. © 2014 Elsevier B.V. All rights reserved.Öğe Experimental and theoretical FTiR and FT-Raman spectroscopic analysis of 1-pyrenecarboxylic acid(Elsevier B.V., 2013) Karabacak M.; Cinar M.; Kurt M.; Chinna Babu P.; Sundaraganesan N.The title molecule 1-pyrenecarboxylic acid (1PCA) has been characterized by FTiR, FT-Raman, NMR and UV-Vis spectral analyses. The molecular geometry, harmonic vibrational modes, the corresponding wavenumbers and iR intensities of 1PCA were calculated by DFT method with 6-311G(d, p) basis set. The assignments of the fundamentals were proposed on the basis of total energy distribution (TED) calculations. The calculated 13C and 1H NMR chemical shifts using gauge including atomic orbitals (GiAOs) approach are in good agreement with the observed chemical shifts. The polarizability and first order hyperpolarizability of the title molecule were calculated and interpreted. Using TD-DFT method, the electronic transitions have been compared with the experimental wavelengths. The molecular electrostatic potential map was used for prediction of possible hydrogen and oxygen bonding sites 1PCA molecule. © 2013 Elsevier B.V. All rights reserved.Öğe An experimental and theoretical investigation of Acenaphthene-5-boronic acid: Conformational study, NBO and NLO analysis, molecular structure and FT-IR, FT-Raman, NMR and UV spectra(Elsevier B.V., 2013) Karabacak M.; Sinha L.; Prasad O.; Asiri A.M.; Cinar M.The solid state Fourier transform infrared (FT-IR) and FT-Raman spectra of Acenaphthene-5-boronic acid (AN-5-BA), have been recorded in the range 4000-400 cm1 and 4000-10 cm 1, respectively. Density functional theory (DFT), with the B3LYP functional was used for the optimization of the ground state geometry and simulation of the infrared and Raman spectra of the molecule. The vibrational wave numbers and their assignments were examined theoretically using the Gaussian 09 set of quantum chemistry codes and the normal modes were assigned by a scaled quantum mechanical (SQM) force field approach. Hydrogen-bonded dimer of AN-5-BA, optimized by counterpoise correction, has also been studied by B3LYP at the 6-311++G(d,p) level and the effects of molecular association through O-H·O hydrogen bonding have been discussed. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by Gauge-Including Atomic Orbital (GIAO) method. Natural bond orbital (NBO) analysis has been applied to study stability of the molecule arising from charge delocalization. UV spectrum of the title compound was also recorded and the electronic properties, such as frontier orbitals, and band gap energies were measured by TD-DFT approach. The first order hyperpolarizability (?), its components and associated properties such as average polarizability and anisotropy of the polarizability (? and ??) of AN-5-BA was calculated using the finite-field approach. © 2013 Elsevier B.V. All rights reserved.Öğe FT-IR, FT-Raman, NMR, UV and quantum chemical studies on monomeric and dimeric conformations of 3,5-dimethyl-4-methoxybenzoic acid(2014) Karabacak M.; Sinha L.; Prasad O.; Asiri A.M.; Cinar M.; Shukla V.K.Extensive spectroscopic investigations along with theoretical quantum chemical studies on 3,5-dimethyl-4-methoxybenzoic acid (DMMBA) have been consummated. The fundamental vibrational transitions were addressed by experimental FT-IR (4000-400 cm -1 ) and FT-Raman (4000-10 cm -1 ) techniques and density functional calculations at B3LYP/6-311++G(d,p) and B3LYP/6-311++G(df,pd) levels of theory. The 1 H, 13 C and DEPT 135 NMR spectra of studied compound were recorded in deuterated dimethylsulfoxide (DMSO -d6 ), and compared with computed data obtained by using gauge including atomic orbital (GIAO) method. The electronic absorption spectra in methanol and ethanol solution were evaluated in the range of 200-400 nm, and TD-DFT method was chosen for computational study. The spectroscopic and theoretical results were compared to the corresponding properties for monomer and dimer structures for the most stable conformer. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. Moreover, the thermodynamic and nonlinear optical (NLO) properties were evaluated. © 2013 Elsevier B.V. All rights reserved.Öğe Identification of structural and spectral features of synthesized cyano-stilbene dye derivatives: A comparative experimental and DFT study(Elsevier, 2014) Karabacak M.; Asiri A.M.; Al-Youbi A.O.; Qusti A.H.; Cinar M.The synthesized three dye derivatives of cyano-stilbene monomer were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with the nonlinear optical (NLO) properties of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR and FT-Raman spectrometry in the range of 4000-400 cm-1 and 3600-50 cm-1, respectively. The theoretical ground state equilibrium conformations and vibrational wavenumbers were carried out by using density functional method with 6-311G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The UV absorption spectra of monomers were observed in the range of 200-600 nm in chloroform, acetonitrile and toluene, and time dependent DFT method was used to obtain the electronic properties. The linear polarizability and first hyperpolarizability of the studied molecules indicates that the title compounds can be used as a good nonlinear optical material. A detailed description of spectroscopic behaviors of compounds was given based on the comparison of experimental measurements and theoretical computations. © 2013 Elsevier B.V. All rights reserved.Öğe The infrared, Raman, NMR and UV spectra, ab initio calculations and spectral assignments of 2-amino-4-chloro-6-methoxypyrimidine(Elsevier B.V., 2013) Cinar Z.; Karabacak M.; Cinar M.; Kurt M.; Chinna Babu P.; Sundaraganesan N.(Graph Presented) The 2-amino-4-chloro-6-methoxypyrimidine abbreviated as ACMP have been investigated by both the experimental and theoretical methods; through this work we provide the essential fact about the structural and vibrational insights. The optimized molecular structure, atomic charges, vibrational frequencies and ultraviolet spectral interpretation of ACMP have been studied by performing DFT/B3LYP/6-311++G(df,pd) level of theory. The FT-IR, FT-Raman spectra were recorded in the region 4000-400 cm -1 and 4000-50 cm-1 respectively. The UV absorption spectrum of the compound that dissolved in ethanol and water solution were recorded in the range of 200-400 nm. The scaled wavenumbers are compared with the experimental values. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. Based on the UV spectrum and TD-DFT calculations, the electronic structure and the assignments of the absorption bands were carried out. The 1H, 13C and DEPT 135 nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated using with the Gauge Including Atomic Orbital (GIAO) method and compared with experimental results. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis were investigated using theoretical calculations. © 2013 Elsevier B.V. All rights reserved.Öğe Molecular structure, electronic properties, NLO, NBO analysis and spectroscopic characterization of Gabapentin with experimental (FT-IR and FT-Raman) techniques and quantum chemical calculations(2013) Sinha L.; Karabacak M.; Narayan V.; Cinar M.; Prasad O.Gabapentin (GP), structurally related to the neurotransmitter GABA (gamma-aminobutyric acid), mimics the activity of GABA and is also widely used in neurology for the treatment of peripheral neuropathic pain. It exists in zwitterionic form in solid state. The present communication deals with the quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of GP using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. In view of the fact that amino acids exist as zwitterions as well as in the neutral form depending on the environment (solvent, pH, etc.), molecular properties of both the zwitterionic and neutral form of GP have been analyzed. The fundamental vibrational wavenumbers as well as their intensities were calculated and compared with experimental FT-IR and FT-Raman spectra. The fundamental assignments were done on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. The electric dipole moment, polarizability and the first hyperpolarizability values of the GP have been calculated at the same level of theory and basis set. The nonlinear optical (NLO) behavior of zwitterionic and neutral form has been compared. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using natural bond orbital analysis. Ultraviolet-visible (UV-Vis) spectrum of the title molecule has also been calculated using TD-DFT method. The thermodynamic properties of both the zwitterionic and neutral form of GP at different temperatures have been calculated. © 2013 Elsevier B.V. All rights reserved.Öğe Qualitative and quantitative structure-activity relationships studies of quercetin derivatives as chemotherapeutic activity(American Scientific Publishers, 2018) Rouane A.; Tchouar N.; Kerassa A.; Cinar M.; Belaidi S.Qualitative and Quantitative structure activity relationship (SAR/QSAR) analysis was applied to eighteen Quercetin derivatives using a combination of various physicochemical, steric, electronic, and structural molecular descriptors. A multiple linear regression (MLR) procedure was used to model the relationships between molecular descriptors and the chemotherapeutic activity of the Quercetin derivatives. The stepwise regression method was used to derive the most significant models as a calibration model for predicting the inhibitory activity of this class of molecules. The best QSAR models were further validated by a leave one out technique as well as by the calculation of statistical parameters for the established theoretical models. High agreement between experimental and predicted inhibitory values, obtained in the validation procedure, indicated the good quality of the derived QSAR models. Copyright © 2018 American Scientific Publishers All rights reservedÖğe Spectral features, electric properties, NBO analysis and reactivity descriptors of 2-(2-Benzothiazolylthio)-Ethanol: Combined experimental and DFT studies(Elsevier, 2015) Srivastava R.; Sinha L.; Karabacak M.; Prasad O.; Pathak S.K.; Asiri A.M.; Cinar M.(Chemical Equation Presented). Quantum chemical calculations of ground state energy, geometrical structure and vibrational wavenumbers, nuclear magnetic behaviors, electronic absorption spectra along with the nonlinear optical properties of 2-(2-benzothiazolylthio)-ethanol (BTZTE) were carried out using density functional (DFT/B3LYP) method with 6-311++G(d,p) as basis set. The FT-IR and FT-Raman spectra were measuredinthe condensed state. The fundamental vibrational wavenumbers as well as their intensities were calculated, and a good correlation between experimental and scaled calculated wavenumbers was accomplished. The electric dipole moment, polarizability and the first hyperpolarizability values of the BTZTE were calculated at the same level of theory and basis set. The results show that the BTZTE molecule possesses nonlinear optical (NLO) behavior with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis. UV spectrum of the studied molecule was recorded in the region 200-500 nm and the electronic properties were predicted by time-dependent DFT approach. The calculated transition energies are in good concurrency with the experimental data. 1 H nuclear magnetic resonance (NMR) chemical shifts of the title molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. The thermodynamic properties of the studied compound at different temperatures were calculated. Global and local reactivity descriptors were computed to predict reactivity and reactive sites on the molecule. © 2014 Elsevier B.V. All rights reserved.Öğe The spectroscopic (FT-IR, FT-Raman, UV and NMR) first order hyperpolarizability and HOMO-LUMO analysis of dansyl chloride(Elsevier, 2014) Karabacak M.; Cinar M.; Kurt M.; Poiyamozhi A.; Sundaraganesan N.The solid phase FT-IR and FT-Raman spectra of dansyl chloride (DC) have been recorded in the regions 400-4000 and 50-4000 cm-1, respectively. The spectra have been interpreted in terms of fundamentals modes, combination and overtone bands. The structure of the molecule has been optimized and the structural characteristics have been determined by density functional theory (B3LYP) method with 6-311++G(d,p) as basis set. The vibrational frequencies were calculated for most stable conformer and were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. The infrared and Raman spectra have also been predicted from the calculated intensities. 1H and 13C NMR spectra were recorded and 1H and 13C nuclear magnetic resonance chemical shifts of the molecule were calculated using the gauge independent atomic orbital (GIAO) method. UV-Visible spectrum of the compound was recorded in the region 200-600 nm and the electronic properties HOMO and LUMO energies were measured by time-dependent TD-DFT approach. Nonlinear optical and thermodynamic properties were interpreted. All the calculated results were compared with the available experimental data of the title molecule. © 2013 Elsevier B.V. All rights reserved.Öğe Structural investigation, drug likeness scoring and structure activity/property relationships applied on 1,2,3-thiadiazole derivatives, with kinase inhibitors activity(Editura Academiei Romane, 2017) Oukil O.; Tchouar N.; Belaidi S.; Salah T.; Cinar M.All calculations and the equilibrium geometries of 1,2,3-thiadiazole have been performed using ab initio/HF, MP2 and DFT methods with different basis sets. The molecular electrostatic potential surface (MESP) that reveals centers of reactivity of the molecule and substitution effects of the molecular system have been studied using the HSAB principle (Hard Soft Acid and Base). Also, the multi-parameter optimization (MPO) methods and structure activity/property relationship studies were carried out on twenty-one molecules of 1,2,3-thiadiazole derivatives which are potent VEGFR-2/KDR kinase inhibitors. In the present work results such as net charges, bond lengths, dipole moments, QSAR properties, Lipinski’s parameters, Lipophilic Efficiency (LipE), have been calculated and discussed. (Figure Presented). © 2017, Editura Academiei Romane. All rights reserved.Öğe Structure'activity relationships and quantitative structure'activity relationships modeling of some 3-(aryl)-N-(aryl)-1,2,4-Oxadiazol-5-Amine derivatives as anti-proliferative agents(American Scientific Publishers, 2015) Belaidi S.; Kerassa A.; Lanez T.; Cinar M.Quantitative structure activity relationship studies were performed on a series of 3-(aryl)-N-(aryl)- 1,2,4-oxadiazol-5-amines as anti-proliferative agents, multiple linear regression analysis was performed to derive quantitative structure activity relationship models which were further evaluated internally for the prediction of activity. The developed models were cross-validated by the 'leave one out' technique as well as by the calculation of statistical parameters. The best QSAR model i.e., model-2 (R2 = 0 906, Fischer's test value F = 12066) has acceptable statistical quality and predictive potential as indicated by the value of cross validated squared correlation coefficient (q2 = 0 907). The present investigation indicates the importance of the quantum chemical descriptors, constitutional descriptors and hydrophobicity to study the anti-proliferative activity. © 2015 American Scientific Publishers All rights reserved.Öğe Synthesis, conformational and spectroscopic characterization of monomeric styrene derivatives having pendant p-substituted benzylic ether groups(2013) Cinar M.; Ozcan L.; Karabacak M.; Erol I.Three derivatives of styrene monomer, 4-chlorophenyl-4-vinylbenzyl ether (I), 4-methoxyphenyl-4-vinylbenzyl ether (II) and 4-ethylphenyl-4-vinylbenzyl ether (III) were synthesized. The synthesized two novel compounds (I and III) and one with undefined structural features were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with chemical shifts of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR spectrometry in the range of 4000-400 cm-1. The computational vibrational wavenumbers and also ground state equilibrium conformations were carried out by using density functional method with 6-311++G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. Isotropic chemical shift of hydrogen and carbon nuclei were investigated via observed 1H and 13C NMR spectra in deuterated DMSO solution and predicted data applied with gauge-invariant atomic orbitals (GIAOs) method. The UV absorption spectra of monomers were observed in the range of 200-800 nm in ethanol, and time dependent DFT method was used to obtain the electronic properties. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. © 2013 Elsevier B.V. All rights reserved.
