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1.
Artigo em Inglês | MEDLINE | ID: mdl-26142173

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 2-[(E)-2-(2-bromophenyl)ethenyl]quinoline-6-carboxylic acid have been investigated experimentally and theoretically using Gaussian09 software package. Potential energy distribution of the normal modes of vibrations was done using GAR2PED program. (1)H NMR chemical shifts calculations were carried out by using B3LYP functional with SDD basis set. The HOMO and LUMO analysis is 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. MEP was performed by the DFT method and the predicted infrared intensities and Raman activities have also been reported. The calculated geometrical parameters are in agreement with that of similar derivatives. The title compound forms a stable complex with PknB as is evident from the binding affinity values and the molecular docking results suggest that the compound might exhibit inhibitory activity against PknB and this may result in development of new anti-tuberculostic agents.


Assuntos
Ácidos Carboxílicos/química , Teoria Quântica , Quinolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Espectrofotometria Ultravioleta , Eletricidade Estática
2.
Artigo em Inglês | MEDLINE | ID: mdl-26142174

RESUMO

FT-IR spectrum of 3-Methyl-4-{(E)-[4-(methylsulfanyl)-benzylidene]amino}1H-1,2,4-triazole-5(4H)-thione was recorded and analysed. The vibrational wavenumbers were computed and at HF and DFT levels of theory. The data obtained from wavenumber calculations are used to assign the vibrational bands obtained in the IR spectrum. The NH stretching wavenumber is red shifted in the IR spectrum from the computed value, which indicates the weakening of the NH bond. The geometrical parameters of the title compound are in agreement with the XRD results. NBO analysis, HOMO-LUMO, first and second order hyperpolarizability and molecular electrostatic potential results are also reported. From the MEP map it is evident that the negative regions are localized over the sulphur atoms and N3 atom of triazole ring and the maximum positive region is localized on NH group, indicating a possible site for nucleophilic attack. Prediction of Activity Spectra analysis of the title compound predicts anti-tuberculostic activity with probability to be active value of 0.543. Molecular docking studies reveal that the triazole nitrogen atoms and the thione sulphur atom play vital role in bonding and results draw us to the conclusion that the compound might exhibit anti-tuberculostic activity.


Assuntos
Compostos de Benzil/química , Simulação de Acoplamento Molecular , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Triazóis/química , Elétrons , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Espectrofotometria Ultravioleta , Eletricidade Estática , Tionas/química
3.
Artigo em Inglês | MEDLINE | ID: mdl-26143326

RESUMO

FT-IR and FT-Raman spectra of (2E)-N-(4-chloro-2-oxo-1,2-dihydroquinolin-3-yl)-3-phenylprop-2-enamide were recorded and analyzed experimentally and theoretically. The synthesis, (1)H NMR and PES scan results are also discussed. Nonlinear optical behavior of the examined molecule was investigated by the determination of first hyperpolarizability. The calculated HOMO and LUMO energies show the chemical activity of the molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. From the MEP it is evident that the negative charge covers the carbonyl group and the positive region is over the NH group. The calculated geometrical parameters (SDD) are in agreement with that of similar derivatives. Molecular docking simulations against targets from Mycobacterium tuberculosis are reported and the results suggest that the compound might exhibit inhibitory activity against PknB.


Assuntos
Amidas/química , Simulação de Acoplamento Molecular , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Teoria Quântica , Quinolinas/química , Vibração , Amidas/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Modelos Moleculares , Mycobacterium tuberculosis/efeitos dos fármacos , Quinolinas/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
4.
Artigo em Inglês | MEDLINE | ID: mdl-26143327

RESUMO

FT-IR and FT-Raman spectra of bis[(E)-anthranyl-9-acrylic]anhydride were recorded and analyzed. The conformational behavior is also investigated. The vibrational wave numbers were calculated using density functional theory (DFT) quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in Infrared and Raman spectra. Potential energy distribution was done using GAR2PED program. The geometrical parameters are compared with related structures. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using Natural Bonding Orbital (NBO) analysis. The Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis are used to determine the charge transfer within the molecule. Molecular Electrostatic Potential (MEP) was performed by the DFT method. The calculated first hyperpolarizability of the title compound is comparable with the reported values of similar derivatives and is 4.23 times that of the standard nonlinear optical (NLO) material urea and the title compound and its derivatives are an attractive object for future studies of nonlinear optical properties. To evaluate the in silico antitumor activity of the title compound molecular docking studies were carried out against protein Bcl-xL. The (1)H-NMR spectrum is also reported.


Assuntos
Amidas/química , Anidridos/química , Antracenos/química , Simulação de Acoplamento Molecular , Teoria Quântica , Vibração , Proteína bcl-X/antagonistas & inibidores , Anidridos/farmacologia , Antracenos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Dinâmica não Linear , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 151: 965-79, 2015 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-26188703

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 2-(4-methoxyphenyl)-4,5-dimethyl-1H-imidazole 3-oxide have been investigated experimentally and theoretically. Gauge-including atomic orbital (1)H NMR chemical shifts calculations were carried out and compared with experimental data. The HOMO and LUMO analysis is 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. The calculated geometrical parameters are in agreement with that of similar derivatives. Molecular electrostatic potential was performed by the DFT method. Mulliken's net charges have been calculated and compared with the atomic natural charges. First and second hyperpolarizability are calculated in order to find its role in non-linear optics. Molecular docking is also reported.


Assuntos
Óxidos N-Cíclicos/química , Imidazóis/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Espectrofotometria Infravermelho , Análise Espectral Raman , Vibração
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 150: 533-42, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26079511

RESUMO

FT-IR and FT-Raman spectra of ethyl 3-(E)-(anthracen-9-yl)prop-2-enoate were recorded and analyzed. The conformational behavior of the molecule was also investigated. The vibrational wavenumbers were calculated using DFT quantum chemical calculations. The data obtained from the wavenumber calculations were used to assign vibrational bands obtained experimentally. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis were used to determine the charge transfer within the molecule and quantum chemical parameters related to the title compound. From the MEP analysis, it is clear that the negative electrostatic potential regions are mainly localized over the carbonyl groups and anthracene ring and are possible sites for electrophilic attack and the positive regions are localized at all the hydrogen atoms as possible sites for nucleophilic attack. NLO and NMR studies are also reported. Molecular docking studies suggest that the title compound might exhibit inhibitory activity against IDE and may act as an insulysin inhibitor. Conformational analysis is also reported.


Assuntos
Acrilatos/química , Antracenos/química , Acrilatos/farmacocinética , Antracenos/farmacocinética , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática , Vibração
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 150: 543-56, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26079512

RESUMO

The Fourier-Transform Infrared and Fourier-Transform Raman spectra of 2,2-diphenyl-4-(piperidin-1-yl)butanamide were recorded in the region 4000-400 cm(-1) and 4000-0 cm(-1). The vibrational wavenumbers are computed using HF and DFT methods. The complete vibrational assignments were performed on the basis of potential energy distribution using GAR2PED program. The geometrical parameters of the title compound are in agreement with the XRD data. From the MEP study, the negative electrostatic potential regions are mainly localized of carbonyl group and are possible sites for electrophilic attack and the positive regions are localized all the rings, indicating possible sites for nucleophilic attack. Stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using natural bond orbital analysis. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. PASS analysis of the title compound predicts among other activities, antidyskinetic activity. Molecular docking results draw us to the conclusion that the compound might exhibit inhibitory activity against adenosine A2A and may act as antidyskinetic agent.


Assuntos
Amidas/química , Compostos de Bifenilo/química , Piperidinas/química , Amidas/farmacocinética , Compostos de Bifenilo/farmacocinética , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Piperidinas/farmacocinética , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática , Vibração
8.
Artigo em Inglês | MEDLINE | ID: mdl-26046498

RESUMO

FT-IR and FT-Raman spectra of 2-[(E)-2-phenylethenyl]quinoline-5-carboxylic acid were recorded and obtained and analyzed. The vibrational wavenumbers were computed using DFT quantum chemical calculations. The geometrical parameters (SDD) of the title compound are in agreement with that of similar derivatives. Stability of the molecule arising from the hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital analysis. From the natural and Mulliken charges, it can be concluded that electrophilic substitution of the quinoline scaffold is more preferred than nucleophilic substitution. From the MEP map it is evident that the negative regions are mainly localized over the carbonyl group and are possible sites for electrophilic attack. The title compound forms a stable complex with PknB as is evident from the binding affinity values and the molecular docking study suggests that the compound might exhibit inhibitory activity against PknB.


Assuntos
Ácidos Carboxílicos/química , Quinolinas/química , Modelos Moleculares , Conformação Molecular , Simulação de Acoplamento Molecular , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Vibração
9.
Artigo em Inglês | MEDLINE | ID: mdl-25863456

RESUMO

FT-IR spectrum of (2E)-3-(3-nitrophenyl)-1-[4-piperidin-1-yl]prop-2-en-1-one was recorded and analyzed. The vibrational wavenumbers were computed using HF and DFT quantum chemical calculations. The data obtained from wavenumber calculations are used to assign IR bands. Potential energy distribution was done using GAR2PED software. The geometrical parameters of the title compound are in agreement with the XRD results. NBO analysis, HOMO-LUMO, first and second hyperpolarizability and molecular electrostatic potential results are also reported. The possible electrophile attacking sites of the title molecule is identified using MEP surface plot study. Molecular docking results predicted the anti-leishmanic activity for the compound.


Assuntos
Antiprotozoários/química , Nitrocompostos/química , Piperidinas/química , Antiprotozoários/farmacologia , Descoberta de Drogas , Humanos , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Simulação de Acoplamento Molecular , Nitrocompostos/farmacologia , Piperidinas/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
10.
Artigo em Inglês | MEDLINE | ID: mdl-25863457

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of Methyl N-({[2-(2-methoxyacetamido)-4-(phenylsulfanyl) phenyl]amino} [(methoxycarbonyl)imino]methyl)carbamate have been investigated using HF and DFT levels of calculations. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential study was also performed. The first and second hyperpolarizability was calculated in order to find its role in nonlinear optics. Molecular docking studies are also reported. Prediction of Activity Spectra analysis of the title compound predicts anthelmintic and antiparasitic activity as the most probable activity with Pa (probability to be active) value of 0.808 and 0.797, respectively. Molecular docking studies show that both the phenyl groups and the carbonyl oxygens of the molecule are crucial for bonding and these results draw us to the conclusion that the compound might exhibit pteridine reductase inhibitory activity.


Assuntos
Acetamidas/química , Antiparasitários/química , Carbamatos/química , Inibidores Enzimáticos/química , Iminas/química , Aminação , Leishmania/enzimologia , Metilação , Simulação de Acoplamento Molecular , Oxirredutases/antagonistas & inibidores , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 146: 307-22, 2015 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-25819320

RESUMO

In this work, the vibrational spectral analysis was carried out using FT-IR and FT-Raman spectroscopy of 2-(4-hydroxyphenyl)-4,5-dimethyl-1H-imidazole 3-oxide. The computations were performed at DFT levels of theory to get the optimized geometry and vibrational frequencies of the normal modes of the title compound using Gaussian09 software. The complete vibrational assignments of frequencies were made on the basis of potential energy distribution. The calculated HOMO and LUMO energies show the chemical activity of the molecule. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The hyperpolarizability values are reported and the first hyperpolarizability of the title compound is 19.61 times that of standard NLO material urea. From the MEP plot, the negative charge covers the nitro group and the positive region is over the hydroxyl group and N-H part of the imidazole ring. The calculated (1)H NMR results are in good agreement with experimental data. Molecular docking study is also reported.


Assuntos
Imidazóis/química , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 145: 260-269, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25791883

RESUMO

FT-IR and FT-Raman spectra of 4-chlorophenyl quinoline-2-carboxylate were recorded and analyzed. The vibrational wavenumbers were computed using DFT quantum chemical calculations. The data obtained from wavenumber calculations are used to assign vibrational bands obtained experimentally. Potential energy distribution was done using GAR2PED program. The geometrical parameters obtained theoretically are in agreement with the XRD data. NBO analysis, HOMO-LUMO, first hyperpolarizability and molecular electrostatic potential results are also reported. The calculated hyperpolarizability of the title compound is 77.53 times that of the standard NLO material urea and the title compound and its derivatives are attractive object for future studies of nonlinear optical properties. Molecular docking results suggest that the compound might exhibit inhibitory activity against GPb.


Assuntos
Elétrons , Simulação de Acoplamento Molecular , Quinolinas/química , Análise Espectral Raman , Sítio Alostérico , Ligantes , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 143: 213-22, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25733248

RESUMO

FT-IR and FT-Raman spectra of 4-Methylphenylquinoline-2-carboxylate were recorded and analyzed. The structure of the molecule has been optimized and structural characteristics have been determined by density functional theory. The geometrical parameters (DFT) are in agreement with the XRD results. HOMO and LUMO and other chemical properties are reported. Nonlinear optical properties are also reported. A detailed molecular picture of the title compound and its interactions were obtained from NBO analysis. The negative (red and yellow) regions of the MEP are related to electrophilic reactivity and the positive (blue) regions to nucleophilic reactivity, as shown in the MEP plot and the carbonyl group and the phenyl rings are observed as electrophilic. PASS analysis predicts that the 4-Methylphenylquinoline-2-carboxylate might exhibit anti-diabetic activity. Molecular docking results suggest that the compound might exhibit inhibitory activity against GPb.


Assuntos
Ácidos Carboxílicos/química , Hipoglicemiantes/química , Quinolinas/química , Análise de Fourier , Simulação de Acoplamento Molecular , Teoria Quântica , Espectrofotometria Infravermelho , Análise Espectral Raman
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 413-24, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25576938

RESUMO

Vibrational spectral analysis of 2-[(4-chlorobenzyl)sulfanyl]-4-(2-methylpropyl)-6-(phenylsulfanyl)-pyrimidine-5-carbonitrile was carried out using FT-IR and FT-Raman spectroscopic techniques. The equilibrium geometry and vibrational wave numbers have been computed using density functional B3LYP method with 6-311++G(d,p)(5D,7F) as basis set. Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using NBO analysis. The nonlinear optical behavior of the title compound is also theoretically predicted. From the MEP, it is evident that the negative charge covers the C≡N group and the positive region is over the phenyl and the pyrimidine rings. From the potential energy scan it is clear that the lone pairs of the sulfur atom prefer to point away from the pyrimidine ring and the C≡N group resulting with two possible minimum conformations at the N4C8S1C25 angle equal nearly 0° or 150°. Molecular docking results suggest that the compound might exhibit inhibitory activity against GPb and may act as potential anti-diabetic compound.


Assuntos
Antineoplásicos/farmacologia , Elétrons , Simulação de Acoplamento Molecular , Pirimidinas/química , Pirimidinas/farmacologia , Análise Espectral Raman , Eletricidade Estática , Vibração , Antineoplásicos/química , Ligação de Hidrogênio , Ligantes , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 483-93, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448949

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]ethanone have been investigated experimentally and theoretically. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. From the MEP it is evident that the negative charge covers the carbonyl group and the positive region is over the remaining groups. The more electronegativity in the carbonyl group makes it the most reactive part in the molecule. First hyperpolarizability is calculated in order to find its role in nonlinear optics. From the molecular docking studies, it is evident that the fluorine atom attached to benzene ring and ethanone attached to the pyrazoline ring are crucial for binding and the compound might exhibit inhibitory activity against TPII and may act as anti-neoplastic agent.


Assuntos
Elétrons , Simulação de Acoplamento Molecular , Pirazóis/química , Eletricidade Estática , Domínio Catalítico , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/metabolismo , Humanos , Ligação de Hidrogênio , Ligantes , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Prótons , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 473-82, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448948

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 1-[5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone have been investigated experimentally and theoretically using Gaussian09 software package. The title compound was optimized using the HF/6-31G(d) (6D, 7F), B3LYP/6-31G (6D, 7F) and B3LYP/6-311++G(d,p) (5D, 7F) calculations. The B3LYP/6-311++G(d,p) (5D, 7F) results and in agreement with experimental infrared bands. The geometrical parameters are in agreement with XRD data. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential was also performed. From the MEP it is evident that the negative charge covers the C=O group and the positive region is over the rings. First hyperpolarizability is calculated in order to find its role in nonlinear optics. Molecular docking studies suggest that the compound might exhibit inhibitory activity against TPII and may act as anti-neoplastic agent.


Assuntos
Elétrons , Simulação de Acoplamento Molecular , Pirazóis/química , Vibração , DNA Topoisomerases Tipo II/metabolismo , Humanos , Ligantes , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Pirazóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 520-33, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25448953

RESUMO

FT-IR and FT-Raman spectra of 2-[(4-chlorobenzyl)sulfanyl]-4-(2-methylpropyl)-6-[3-trifluoromethyl)-anilino]pyrimidine-5-carbonitrile were recorded and analyzed. The vibrational wave numbers were computed using DFT quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in infrared and Raman spectra. Potential energy distribution was done using GAR2PED program. The NH stretching wave number is red shifted by 102 cm(-1) in IR from the computed wave number, which indicates the weakening of the NH bond. The geometrical parameters (DFT) of the title compound are in agreement with the XRD results. NBO analysis, HOMO-LUMO, first hyperpolarizability and molecular electrostatic potential results are also reported. From the MEP map it is evident that the negative electrostatic potential regions are mainly localized over the CN and CF3 groups and are possible sites for electrophilic attack and positive regions are localized around NH group, indicating possible sites for nucleophilic attack. The preliminary docking results suggest that the title compound might exhibit inhibitory activity against GPb and may act as a potential anti-diabetic compound.


Assuntos
Hipoglicemiantes/química , Nitrilas/química , Pirimidinas/química , Animais , Glicogênio Fosforilase/metabolismo , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Nitrilas/farmacologia , Pirimidinas/farmacologia , Coelhos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 193-206, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25218229

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 5-tert-Butyl-6-chloro-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 is 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, carbon atoms leads to the elongation of respective bond length and a lowering of the corresponding stretching wave number. 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.


Assuntos
Elétrons , Pirazinas/química , Análise Espectral Raman , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 652-61, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25128678

RESUMO

FT-IR and FT-Raman spectra of 10,10-Dimethylanthrone were recorded and analyzed. The vibrational wavenumbers were computed using DFT quantum chemical calculations. The data obtained from wavenumber calculations are used to assign vibrational bands obtained experimentally. In its most stable form, the title compound maintains C2v symmetry as determined by XRD results, where both methyl groups are staggered with respect to the corresponding C23-C24 and C23-C28 bonds. The geometrical parameters (B3LYP/6-311++G(d,p)(5D,7F)) of the title compound are in agreement with the XRD results. The calculated HOMO and LUMO energies allow the calculations of atomic and molecular properties and they also showed that charge transfer occurs in the molecule. A detailed molecular picture of the title compound and its interactions were obtained from NBO analysis. As seen from the MEP map, negative potential regions are localized over the carbonyl group and are possible sites for electrophilic attack. The title compound, 10,10-Dimethylanthrone forms a stable complex with human topoisomerase-II as is evident from the ligand-receptor interactions and show appreciable antineoplastic activity.


Assuntos
Antracenos/química , Simulação de Acoplamento Molecular , Análise Espectral Raman , Vibração , Domínio Catalítico , DNA Topoisomerases Tipo II/metabolismo , Elétrons , Humanos , Ligantes , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 138: 529-38, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25528512

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde have been investigated experimentally and theoretically. The title compound was optimized using at HF and DFT levels of calculations. The B3LYP/6-311++G(d,p) (5D,7F) results and in agreement with experimental infrared bands. The normal modes are assigned using potential energy distribution. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using natural bonding orbital analysis. The frontier molecular orbital analysis is used to determine the charge transfer within the molecule. From molecular electrostatic potential map, it is evident that the negative electrostatic potential regions are mainly localized over the carbonyl group and mono substituted phenyl ring and are possible sites for electrophilic attack and, positive regions are localized around all para substituted phenyl and pyrazole ring, indicating possible sites for nucleophilic attack. First hyperpolarizability is calculated in order to find its role in nonlinear optics. The geometrical parameters are in agreement with experimental data. From the molecular docking studies, it is evident that the fluorine atom attached to phenyl ring and the carbonyl group attached to pyrazole ring are crucial for binding and the results draw us to the conclusion that the compound might exhibit phosphodiesterase inhibitory activity.


Assuntos
Aldeídos/química , Simulação de Acoplamento Molecular , Fenômenos Ópticos , Pirazóis/química , Catálise , Cristalização , Ligantes , Conformação Molecular , Dinâmica não Linear , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
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