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1.
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
2.
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
3.
Artigo em Inglês | MEDLINE | ID: mdl-24747929

RESUMO

O,O'-dibornyl dithiophosphete has been synthesized by the reaction of P2S5 and borneol in toluene. Fourier Transform Infrared spectra (FT-IR) of the title compound are measured. The molecular geometry, vibrational frequencies, infrared intensities and NMR spectrum of the title compound in the ground state have been calculated by using the density functional theory (DFT) and ab initio Hartree-Fock (HF) methods with the basis set of 6-31G(d). The computed bond lengths and bond angles show the good agreement with the experimental data. Moreover, the vibrational frequencies are calculated and the scaled values have been compared with experimental FT-IR spectra. Assignments of the vibrational modes are made on the basis of total energy distribution (TED) calculated with scaled quantum mechanical (SQM) method. The observed and calculated FT-IR and NMR spectra are in good agreement with each other.


Assuntos
Compostos de Amônio/química , Organotiofosfatos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Teoria Quântica , Sais/química , Espectroscopia de Infravermelho com Transformada de Fourier
4.
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
6.
Eye (Lond) ; 13 ( Pt 2): 241-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10450390

RESUMO

PURPOSE: Interferon alpha, which is used to treat various systemic disorders, has many reversible side-effects involving various organ systems. In this study, chronic active hepatitis patients undergoing interferon alpha therapy were followed with regard to the ocular side-effects. METHODS: Thirty-six patients with chronic active hepatitis undergoing subcutaneous interferon alpha therapy for 1 year were enrolled. Complete ocular examination and photographic documentation were performed at baseline of the therapy and monthly thereafter. Fisher's exact chi-squared test and Mann-Whitney U-test were employed in the statistical evaluation of the results. RESULTS: Trichomegaly was noted in 2 (6%) patients. Fifteen patients (42%) were found to have retinopathy with cotton wool spot formation and splinter haemorrhages. CONCLUSIONS: These findings emphasise the need to monitor these retinal complications, which may result in loss of vision in patients receiving interferon alpha therapy.


Assuntos
Antivirais/efeitos adversos , Hepatite Viral Humana/terapia , Interferon-alfa/efeitos adversos , Doenças Retinianas/etiologia , Adolescente , Adulto , Idoso , Doença Crônica , Pestanas , Feminino , Seguimentos , Doenças do Cabelo/etiologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Acuidade Visual
7.
J Infect ; 37(1): 70-1, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9733385

RESUMO

A case of chronic brucella endocarditis of a prosthetic valve is reported. The diagnosis of this infection was established by positive blood cultures and high brucella agglutination titre. The patient was successfully managed by combination of medical therapy (consisting of streptomycin, trimethoprim-sulphamethoxazole, rifampin and tetracycline) and surgery.


Assuntos
Valva Aórtica/microbiologia , Brucella melitensis/isolamento & purificação , Brucelose/microbiologia , Endocardite Bacteriana/microbiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Adulto , Valva Aórtica/patologia , Brucelose/tratamento farmacológico , Endocardite Bacteriana/tratamento farmacológico , Humanos , Masculino , Cardiopatia Reumática/complicações , Cardiopatia Reumática/cirurgia
8.
Eur J Ophthalmol ; 8(4): 265-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9891901

RESUMO

Fabry's disease is associated with high incidence of thrombosis in hemizygous males and heterozygous females. We describe a woman with Fabry's disease who developed hemi-central retinal vein occlusion during the follow-up. The vein occlusion showed a fulminant course ending with a painful blind eye within a short period. Fabry's disease should be considered in the differential diagnosis of the vascular occlusive disorders especially in young patients.


Assuntos
Doença de Fabry/complicações , Oclusão da Veia Retiniana/etiologia , Adulto , Biópsia , Crioterapia , Diagnóstico Diferencial , Exsudatos e Transudatos , Doença de Fabry/diagnóstico , Feminino , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Glaucoma Neovascular/diagnóstico , Glaucoma Neovascular/etiologia , Humanos , Retina/patologia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Descolamento Retiniano/terapia , Hemorragia Retiniana/diagnóstico , Hemorragia Retiniana/etiologia , Hemorragia Retiniana/terapia , Oclusão da Veia Retiniana/diagnóstico , Oclusão da Veia Retiniana/terapia , Pele/patologia , Acuidade Visual
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