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1.
Kardiologiia ; 63(10): 78-83, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37970859

RESUMO

AIM: Idiopathic dilated cardiomyopathy (DCM) is one of the leading causes of low ejection fraction (EF) heart failure (HF). The Tei index is a reliable marker that reflects both left ventricular (LV) systolic and diastolic function, and it has prognostic value in patients with DCM. We aimed to investigate the relationship between the Tei index and long-term survival in non-ischemic, DCM patients. MATERIAL AND METHODS: The present study included 98 patients with non-ischemic DCM. The mean survival time of the patients was 59 mos. RESULTS: The Tei index was prominently higher in patients who died (0.64±0.08 vs 0.71±0.12, respectively; p=0.01). LV end-systolic volume and LV ejection fraction (LVEF) were independent prognostic factors and predicted worse long-term survival. Additionally, the patients with LVEF ≥32.7 % and the Tei index ≤0.76 had significantly longer survival. CONCLUSION: The present study showed that the Tei index was significantly associated with mortality and the patients with both low LVEF (≤32.7 %) and high Tei index (≥0.76) values had a shorter life expectancy. As a result, we suggest that the Tei index may be a useful echocardiographic marker to predict long-term survival in DCM patients.


Assuntos
Cardiomiopatia Dilatada , Disfunção Ventricular Esquerda , Humanos , Função Ventricular Esquerda , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/complicações , Volume Sistólico , Ecocardiografia , Diástole , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/complicações
2.
Hum Exp Toxicol ; 37(9): 991-1004, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29271245

RESUMO

A total of 66 male Wistar rats were used and six groups (control: 10 animals and experimental: 12 animals) were formed. While a separate control group was established for each study period, mad honey application to the animals in the experimental group was carried out with a single dose (12.5 g kg-1 body weight (b.w.); acute stage), at a dose of 7.5 g kg-1 b.w. for 21 days (subacute stage), and at a dose of 5 g kg-1 b.w. for 60 days (chronic stage). Tissue and blood oxidative stress markers (malondialdehyde (MDA), nitric oxide (NO), 4-hydroxynonenal (HNE), superoxide dismutase, catalase, glutathione (GSH) peroxidase, and glucose-6-phosphate dehydrogenase), hepatic chemical metabolizing parameters in the liver (cytochrome P450 2E1, nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase, nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome c reductase (CYTC), GSH S-transferase (GST), and GSH), and micronucleus and comet test in some samples were examined. Findings from the study showed that single and repeated doses given over the period increased MDA, NO, and HNE levels while decreasing/increasing tissue and blood antioxidant enzyme activities. From hepatic chemical metabolizing parameters, GST activity increased in the subacute and chronic stages and CYTC activity increased in the acute period, whereas GSH level decreased in the subacute stage. Changes in tail and head intensities were found in most of the comet results. Mad honey caused oxidative stresses for each exposure period and made some significant changes on the comet test in certain periods for some samples obtained. In other words, according to the available research results obtained, careless consumption of mad honey for different medical purposes is not appropriate.


Assuntos
Dano ao DNA , Diterpenos/toxicidade , Mel/toxicidade , Fígado/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Ensaio Cometa , Fígado/enzimologia , Fígado/patologia , Masculino , Testes para Micronúcleos , Ratos Wistar , Rhododendron , Fatores de Tempo
3.
Artigo em Inglês | MEDLINE | ID: mdl-27107533

RESUMO

Isophthalic acid (C6H4(CO2H)2) is a noteworthy organic compound widely used in coating and synthesis of resins and the production of commercially important polymers such as drink plastic bottles. The effects of isophthalic acid (IPA) on human health, toxicology, and biodegradability are the main focus of many researchers. Because structural and spectroscopic investigation of molecules provides a deep understanding of interactional behaviors of compounds, this study stands for exploring those features. Therefore, the spectroscopic, structural, electronic, and thermodynamical properties of IPA were thoroughly studied in this work experimentally using UV-Vis, (1)H and (13)C NMR, FT-IR, FT-Raman and theoretically via DFT and TD-DFT calculations. The UV-Vis absorption spectrum in water was taken in the region 200-400nm. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The infrared and Raman spectra of the solid IPA were recorded in the range of 4000-400cm(-1) and 3500-50cm(-1), respectively. DFT and TD-DFT calculations were performed at the level of B3LYP/6-311++G(d,p) in determination of geometrical structure, electronic structure analysis and normal mode. The (13)C and (1)H nuclear magnetic resonance (NMR) spectra were estimated by using the gauge-invariant atomic orbital (GIAO) method. The scaled quantum mechanics (SQM) method was used to determine the total energy distribution (TED) to assign the vibrational modes accurately. Weak interactions such as hydrogen bonding and Van der Walls were analyzed via reduced density gradient (RDG) analysis in monomeric and dimeric forms. Furthermore, the excitation energies, density of state (DOS) diagram, thermodynamical properties, molecular electro-static potential (MEP), and nonlinear optical (NLO) properties were obtained.

4.
Artigo em Inglês | MEDLINE | ID: mdl-26186392

RESUMO

A complete structural and vibrational analysis of the 4-(2,5-di-2-thienyl-1H-pyrrol-1-yl) benzoic acid (TPBA), was carried out by ab initio calculations, at the density functional theory (DFT) method. Molecular geometry, vibrational wavenumbers and gauge including atomic orbital (GIAO) (13)C NMR and (1)H NMR chemical shift values of (TPBA), in the ground state have been calculated by using ab initio density functional theory (DFT/B3LYP) method with 6-311G(d,p) as basis set for the first time. Comparison of the observed fundamental vibrational modes of (TPBA) and calculated results by DFT/B3LYP method indicates that B3LYP level of theory giving yield good results for quantum chemical studies. Vibrational wavenumbers obtained by the DFT/B3LYP method are in good agreement with the experimental data. The study was complemented with a natural bond orbital (NBO) analysis, to evaluate the significance of hyperconjugative interactions and electrostatic effects on such molecular structure. By using TD-DFT method, electronic absorption spectra of the title compound have been predicted and a good agreement with the TD-DFT method and the experimental one is determined. In addition, the molecular electrostatic potential (MEP), frontier molecular orbitals analysis and thermodynamic properties of TPBA were investigated using theoretical calculations.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 151-62, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-25813172

RESUMO

The azocalix[4]arenes molecules such as methylphenylazocalix[4]aren (MPcalix[4]) and methoxyphenylazocalix[4]aren (MOPcalix[4]) have been synthesized and characterized by experimental FT-IR and (1)H NMR spectral analyses. The fundamental vibrational transitions have been addressed by experimental FT-IR (4000-400 cm(-1)) technique and density functional theory (DFT) employing B3LYP level with the 6-31G(d) and 6-311G(d,p) basis sets. The (1)H NMR spectra of the studied compounds have been recorded in chloroform, and compared with computed data obtained by using gauge including atomic orbital (GIAO) method. Furthermore, thermodynamic properties (heat capacity, entropy, and enthalpy changes) and frontier molecular orbitals of the molecules in the ground state have been calculated by using the same method and basis sets. The non-linear optical properties such as the first order hyperpolarizability (ß0), related properties (α0 and Δα) are also computed. Information about the charge density distribution of the molecules and its chemical reactivity has been studied by mapping molecular electrostatic potential surface (MEPs). The scaled vibrational frequency values have been compared with experimental FT-IR spectroscopic data. The correlations between the observed and calculated frequencies are in good agreement with each other as well as the correlation of NMR data. The linear polarizability and first hyperpolarizability of the studied molecules indicate that the compounds are a good candidate of nonlinear optical materials.


Assuntos
Hidrocarbonetos Aromáticos/química , Hidrocarbonetos Aromáticos/síntese química , Modelos Moleculares , Espectroscopia de Ressonância Magnética , Estrutura Molecular
6.
Drug Res (Stuttg) ; 65(4): 219-22, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24992496

RESUMO

In this study*, it was aimed to observe, genotoxic effects of antituberculosis drugs and combinations on rats. Animals were treated with 31.5 mg/kg isoniazid (INH), 54 mg/kg rifampicin (RIF), 189 mg/kg pyrazinamide (PYR), 100 mg/kg etham-butol(ETA), INH+RIF+PYR (MIX1) and INH+RIF+PYR+ETA (MIX2) mixtures applied via gavage for 90 days. At the end of the study, blood, liver and kidney samples were taken and evaluated by Comet and Micronucleus techniques. Compared to control group, head intensity decreased, tail intensity and tail migration increased on experiment groups in blood samples. Head intensity of PYR and mixture groups decreased, tail intensity of PYR and mixture groups increased and tail migration of PYR, ETA and mixture groups increased in liver samples. Head intensity decreased and tail intensity increased of INH, RIF, ETA and MIX1 group; tail migration increased of MIX1 group in kidney samples. Compared to control group, micronucleus rate of ETA, RIF and MIX 2 groups increased in experiment groups. In conclusion antituberculosis drugs and their mixtures applied for 90 days causes to double strand break of DNA damage at different degrees in blood, kidney and liver cells in rats.


Assuntos
Antituberculosos/farmacologia , Dano ao DNA/efeitos dos fármacos , Etambutol/farmacologia , Isoniazida/farmacologia , Pirazinamida/farmacologia , Rifampina/farmacologia , Animais , Antituberculosos/sangue , Antituberculosos/farmacocinética , Combinação de Medicamentos , Etambutol/sangue , Etambutol/farmacocinética , Isoniazida/sangue , Isoniazida/farmacocinética , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pirazinamida/sangue , Pirazinamida/farmacocinética , Ratos , Rifampina/sangue , Rifampina/farmacocinética
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 283-95, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25078461

RESUMO

Comprehensive investigation of geometrical and electronic structure in ground as well as the first excited state of 3,5-Difluoroaniline (C6H5NF2) was carried out. The experimentally observed spectral data (FT-TR and FT-Raman) of the title compound was compared with the spectral data obtained by DFT/B3LYP method using 6-311++G(d,p) basis set. The molecular properties like dipole moment, polarizability, first static hyperpolarizability, molecular electrostatic potential surface (MEPs), and contour map were calculated to get a better insight of the properties of the title molecule. Natural bond orbital (NBO) analysis was applied to study stability of the molecule arising from charge delocalization. UV-Vis 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. Total and partial density of state (TDOS and PDOS) and also overlap population density of state (OPDOS) diagrams analysis were presented. Global and local reactivity descriptors were computed to predict reactivity and reactive sites on the molecule. (1)H and (13)C NMR spectra by using gauge including atomic orbital (GIAO) method of studied compound were compared with experimental data obtained. Moreover, the thermodynamic properties were evaluated.


Assuntos
Compostos de Anilina/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Elétrons , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica , Vibração
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 1315-33, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25305625

RESUMO

In this study, the Fourier Transform Infrared (FT-IR) and Fourier Transform Raman (FT-Raman) spectra of 5-bromo-2-ethoxyphenylboronic acid (5Br2EPBA) are recorded in the solid phase in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. The (1)H, (13)C and DEPT nuclear magnetic resonance (NMR) spectra are recorded in DMSO solution. The UV-Vis absorption spectrum of 5Br2EPBA is saved in the range of 200-400 nm in ethanol and water. The following theoretical calculations for monomeric and dimeric structures are supported by experimental results. The molecular geometry and vibrational frequencies in the ground state are calculated by using DFT methods with 6-31G(d,p) and 6-311G(d,p) basis sets. There are four conformers for the present molecule. The computational results diagnose the most stable conformer of 5Br2EPBA as Trans-Cis (TC) form. The complete assignments are performed on the basis of the total energy distribution (TED) of vibrational modes, calculated with scaled quantum mechanics (SQM) method in parallel quantum solutions (PQS) program. The (1)H and (13)C NMR chemical shifts of 5Br2EPBA molecule are calculated by using the Gauge Invariant Atomic Orbital (GIAO) method in DMSO and gas phase for monomer and dimer structures of the most stable conformer. Moreover, electronic properties, such as the HOMO and LUMO energies (by TD-DFT and CIS methods) and molecular electrostatic potential surface (MEPs) are investigated. Stability of the molecule arising from hyper-conjugative interactions, charge delocalization is analyzed using natural bond orbital (NBO) analysis. Nonlinear optical (NLO) properties and thermodynamic features are presented. All calculated results are compared with the experimental data of the title molecule. The correlation of theoretical and experimental results provides a detailed description of the structural and physicochemical properties of the title molecule.


Assuntos
Ácidos Borônicos/química , Reagentes de Ligações Cruzadas/química , Dimerização , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 306-20, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448934

RESUMO

The spectroscopic (FT-IR, FT-Raman, (1)H and (13)C NMR, UV-Vis), structural, electronic and thermodynamical properties of 3-fluorophenylboronic acid (C6H4FB(OH)2), 3FPBA) were submitted by using both experimental techniques and theoretical methods (quantum chemical calculations) in this work. The experimental infrared and Raman spectra were obtained in the region 4000-400 cm(-1) and 3500-10 cm(-1), respectively. The equilibrium geometry and vibrational spectra were calculated by using DFT (B3LYP) with 6-311++G(d,p) basis set. The vibrational wavenumbers were also corrected with scale factor to take better results for the calculated data. The total energy distributions (TED) of the vibrational modes were performed for the assignments of the title molecule by using scaled quantum mechanics (SQM) method. The NMR chemical shifts ((1)H and (13)C) were recorded in DMSO solution. The (1)H and (13)C NMR spectra were computed by using the gauge-invariant atomic orbital (GIAO) method, showing a good agreement with the experimental ones. The last one UV-Vis absorption spectra were analyzed in two solvents (ethanol and water), saved in the range of 200-400 nm. In addition these, HOMO and LUMO energies, the excitation energies, density of states (DOS) diagrams, thermodynamical properties and molecular electrostatic potential surface (MEPs) were presented. Nonlinear optical (NLO) properties and thermodynamic features were performed. The experimental results are combined with the theoretical calculations using DFT calculations to fortification of the paper. At the end of this work, the results were proved our paper had been indispensable for the literature backing.


Assuntos
Ácidos Borônicos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Dimerização , Elétrons , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica , Vibração
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 451-63, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448946

RESUMO

The optimized molecular structure and corresponding vibrational assignments of 2-tert-butyl-5-methyl anisole (TBMA) have been investigated using density functional theory (DFT)/B3LYP with 6-31G(d,p) and 6-311++G(d,p) basis sets investigation of the relative orientation of the methoxy group has shown two conformers (O-cis) and (O-trans) exist. The vibrational analysis of the stable conformer of the title compound is performed by means of infrared absorption and Raman spectroscopy in combination with theoretical simultaneously. The natural bond orbital (NBO) analysis is useful to understand the intra-molecular hyper conjugative interaction lone pair and π(∗)(C-C), σ(∗)(C-H) bond orbital. HOMO and LUMO energies show that charge transfer occurs in the molecule, therefore; HOMO, LUMO and molecular electrostatic potential (MEP) were calculated and analyzed. (1)H and (13)C NMR spectra by using gauge including atomic orbital (GIAO) method of studied compound were compared with experimental data. The thermodynamic functions of TBMA were calculated by B3LYP/6-311+G(d,p) basis set.


Assuntos
Anisóis/química , Elétrons , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Conformação Molecular , Espectroscopia de Prótons por Ressonância Magnética , Rotação , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica , Vibração
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 607-17, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448961

RESUMO

In this study, 5,17-di(2-antracenylazo)-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene has been synthesized from 2-aminoantracene and 25,27-dihydroxy-26,28-diethylacetate calix[4]arene. In order to identify the molecular structure and vibrational features of the prepared azocalix[4]arene, FT-IR and (1)H NMR spectral data have been used. FT-IR spectrum of the studied molecule is recorded in the region 4000-400 cm(-1). (1)H NMR spectrum is recorded for 0.1-0.2 M solutions in DMSO-d6 solution. The molecular geometry, infrared spectrum are calculated by the density functional method employing B3LYP level with different basis sets, including 6-31G(d) and LanL2DZ. The chemical shifts calculation for (1)H NMR of the title molecule is calculated by using by Gauge-Invariant Atomic Orbital method by utilizing the same basis sets. The total density of state, the partial density of state and the overlap population density of state diagram analysis are done via GaussSum 3.0 program. Frontier molecular orbital (HOMO-LUMO) and molecular electrostatic potential surface on the title molecule are carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement.


Assuntos
Calixarenos/química , Calixarenos/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt C: 1205-15, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448982

RESUMO

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 measured in the 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 200-500nm 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.

13.
Br Poult Sci ; 55(6): 785-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25333932

RESUMO

1. This study was conducted to determine the effects of hempseed (HS) on performance, egg traits, serum lipid profile and antioxidant activity in Japanese quail (Coturnix coturnix japonica). 2. A total of 120 eight-week-old laying quail were divided into 4 experimental groups with 10 replicates. The treatments were as follows: (1) control diet (C, no HS in the diet); (2) 5% HS in the diet (HS5); (3) 10% HS in the diet (HS10); and (4) 20% HS in the diet (HS20). The quail were fed the experimental diets from 8 to 14 weeks of age. 3. There was no significant difference in body weight, feed intake and feed conversion ratio of the birds overall in the experiment. The egg production was not influenced by the HS contents in the diet; however the HS10 diet increased egg weight and egg-specific gravity. The carcass traits were not affected by the HS contents. 4. The serum triglyceride, cholesterol and the high density lipoprotein were not significantly altered; however, low density lipoprotein (LDL) concentration in HS-supplemented groups were lower than that of the C group. 5. The malondialdehyde, superoxide dismutase, catalase and nitrogen oxide concentrations were not significantly affected, but in the HS10 and HS20, glutathione peroxidase (GSH-Px) concentration was higher than in the C and HS5 groups. 6. The omega-3 fatty acid content of eggs increased linearly with increasing dietary HS content in the diet. 7. In conclusion, HS could be a potential feed and health benefit as a natural antioxidant in relation to decreasing serum LDL and increasing GSH-Px concentration in the liver of laying quail.


Assuntos
Cannabis , Coturnix/crescimento & desenvolvimento , Suplementos Nutricionais , Ovos/normas , Animais , Colesterol/sangue , Coturnix/sangue , Dieta/veterinária , Feminino , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Oviposição/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Triglicerídeos/sangue
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 133: 165-77, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24934975

RESUMO

FT-IR and FT-Raman spectra of anethole (1-Methoxy-4-(1-propenyl)benzene), a flavoring agent of commercial value, have been recorded in the regions 4000-400 and 4000-100cm(-1) respectively. The structure of the title molecule has been optimized and the structural parameters have been calculated by DFT/B3LYP method with 6-311++G(d,p) basis set. The fundamental vibrational wavenumbers as well as their intensities were calculated and a good agreement between observed and scaled calculated wavenumbers has been achieved. UV-Vis spectrum of the title compound was recorded in the region 200-500nm and the electronic properties such as HOMO and LUMO energies and associated energy gap were calculated by Time dependent-density functional theory (TD-DFT) approach. Nonlinear optical (NLO) study divulges the nonlinear properties of the molecule. Stability of the title molecule arising from hyper-conjugative interactions and charge delocalization has been investigated using natural bond orbital (NBO) analysis. The theoretical results were found to be in coherence with the measured experimental data.


Assuntos
Anisóis/química , Aromatizantes/química , Derivados de Alilbenzenos , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 117: 234-44, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-23994679

RESUMO

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. (1)H and (13)CNMR spectra were recorded and (1)H and (13)C 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.


Assuntos
Compostos de Dansil/química , Espectroscopia de Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Elétrons , Entropia , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Teoria Quântica , Termodinâmica , Vibração
16.
Artigo em Inglês | MEDLINE | ID: mdl-24177879

RESUMO

Molecular geometry and vibrational wavenumbers of 2(3H)-Benzothiazolone (C7H5NSO, HBT) was investigated using density functional (DFT/B3LYP) method with 6-311+G(d,p) basis set. The vibrational wavenumbers are found to be in good agreement with experimental FT-IR spectra. Hydrogen-bonded dimer of HBT, optimized by counterpoise correction, was studied by MP2 and DFT/B3LYP at the 6-311+G(d,p) level and the effects of molecular association through NH---O hydrogen bonding were discussed. A detailed analysis of the nature of the hydrogen bonding, using topological parameters, such as electronic charge density, Laplacian, kinetic and potential energy density evaluated at bond critical points (BCP) has also been presented. The UV absorption spectra of the compound dissolved in ethanol and chloroform solutions were recorded in the range of 200-600 nm. The UV-vis spectrum of the title molecule was also calculated using TD-DFT method. The calculated energy and oscillator strength almost exactly reproduce the experimental data. Total and partial density of state (TDOS, PDOS) of the HBT in terms of HOMOs and LUMOs and molecular electrostatic potential (MEP) were calculated and analyzed. The electric dipole moment, polarizability and the first static hyper-polarizability values for HBT were calculated at the DFT/B3LYP with 6-311+G(d,p) basis set. The results also show that the HBT molecule may have nonlinear optical (NLO) comportment with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization was analyzed using natural bond orbital (NBO) analysis.


Assuntos
Benzotiazóis/química , Dimerização , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Artigo em Inglês | MEDLINE | ID: mdl-24177881

RESUMO

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.


Assuntos
Corantes/química , Estilbenos/química , Modelos Moleculares , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 122: 582-90, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24334059

RESUMO

The compound 2 has been synthesized from the reaction of 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide and (R)-1-[3,5-Bis(trifloromethyl)phenyl]ethanol in toluene. The obtained crude dithiophosphonic acid 1 has been treated with the excess of N(C2H5)3 to give rise to 2, [(+HN(C2H5)3][O-CH3CH-C6H3(CF3)2)(CH3OC6H4)PS2(-)]. The compound 2 has been characterized by using the spectroscopic methods such as IR, (1)H, (13)C, (31)P NMR and structural analysing method such as X-ray crystallography. It crystallizes in the orthorhombic system, whose space group is P212121. It consists of a dithiophosphonate bridged methoxyphenyl and bis(triflorophenylethyl) groups and a triethylammonium moiety linked by N-H⋯S and C-H⋯F hydrogen bonds. In the crystal structure, the C17H14F6O2PS2 molecule is elongated along the b-axis and stacked along the a-axis. The triethylammonium, N(CH2CH3)3, molecule fill in the cavities between the C17H14F6O2PS2 molecule. Moreover, ab initio methods based on Hartree-Fock (HF) and Density Functional Theory (DFT) calculations with the basis set of 6-31G(d) are also carried out to determine the molecular structural properties and to calculate FT-IR and NMR spectrum of the compound 2. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement.


Assuntos
Compostos Organotiofosforados/química , Cristalografia por Raios X , Etanol/química , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Artigo em Inglês | MEDLINE | ID: mdl-24291448

RESUMO

In this work, the vibrational spectral analysis was carried out by using FT-Raman and FT-IR spectroscopy in the range 4000-100 cm(-1) and 4000-400 cm(-1), respectively, for 4-chloro-N-(2-methyl-2,3-dihydroindol-1-yl)-3-sulfamoyl-benzamide (C16H16O3N3SCl) molecule. Theoretical calculations were performed by density functional theory (DFT) method using 6-31G(d,p) and 6-311G(d,p) basis sets. The complete vibrational assignments of wavenumbers were made on the basis of potential energy distribution (PED). The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The frontier orbital energy gap and dipole moment illustrates the high reactivity of the title molecule. The first order hyperpolarizability (ß0) and related properties (µ, α, and Δα) of the molecule were also calculated. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The UV-vis spectrum of the compound was recorded in the region 200-400 nm in ethanol and electronic properties such as excitation energies, oscillator strength and wavelength were calculated by TD-DFT/B3LYP method. Molecular electrostatic potential (MEP) and HOMO-LUMO energy levels are also constructed. The thermodynamic properties of the title compound were calculated at different temperatures.


Assuntos
Benzamidas/química , Elétrons , Indóis/química , Modelos Moleculares , Análise Espectral Raman , Vibração , Etanol/química , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica
20.
Artigo em Inglês | MEDLINE | ID: mdl-23973593

RESUMO

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 (1)H, (13)C 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.


Assuntos
Citosina/análogos & derivados , Citosina/química , Elétrons , Halogenação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
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