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1.
Heliyon ; 9(10): e20512, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37800076

RESUMO

Optoelectronic and the cubic nonlinear optical properties of 4-(4-Bromophenyl)-2-(4-nitrophenyl)-2, 3-dihydro-1H-1, 5-benzodiazepine have been studied. Z-scan technique was used for the third-order nonlinear optical measurements namely, nonlinear absorption, nonlinear refraction, and optical power limiting behaviour employing an Nd: YAG laser of 532 nm wavelength having 5 ns Gaussian pulses. B3LYP/6-311 ++ G (d, p) level of theory was employed for structural optimization, vibrational wavenumber, frontier molecular orbitals, natural bond orbital and population analysis. The MOLVIB programme was used to perform unambiguous vibrational assignments based on potential energy distribution values acquired from normal coordinate analysis. B3LYP and CAM-B3LYP hybrid functions have been employed at the DFT level to calculate the theoretical second-order hyperpolarizability. The substitution of -NO2 and -Br in this benzodiazepine compound enhances the second-order hyperpolarizability (γ) to the order of 10-34 esu and, switching of self-defocussing to self-focussing phenomenon. The HOMO-LUMO and optical band gap analysis illustrates that polarizing nature of the molecule vary with substituents. The obtained results indicate that this compound has potential applications in optoelectronics and photonics.

2.
Ann Pharm Fr ; 80(6): 837-852, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35489418

RESUMO

For impurity profiling of betamethasone acetate and betamethasone phosphate injectable suspensions, a quick, verified stability indicating UPLC technique incorporating the detectors PDA-QDa had been established. This method with an analysis time of 12min could able to separate all possible degradation impurities. Two of the thermal impurities have been identified in positive mode of detection by using QDa detector and isolated by using preparative HPLC. The method works at a flow rate of 0.5mL/min in column: Poroshell 120 EC C18 (100×2.1)mm, 1.9µm, maintained temperature precisely at 40°C. The M/Z values in ESI positive mode for the two new degradation impurities have been identified (M+H) as 393.22 (DP1), 363.17 (DP2) and confirmed by 1H NMR. The approach was also verified in accordance with the rules of ICH Q2 (R1). From LOQ quantity value to 150% quantity of specified concentration (2% for betamethasone and 0.5% for other impurities), the technique of UPLC-PDA-QDa was proven to be linear and accurate. Precision and ruggedness results showed˂5% RSD. Accuracy results showed more than 95% recovery from LOQ till 150% of impurity specification. This UPLC-PDA-QDa methodology was found specific, precise, stable and robust for quantification of all possible degradation impurities. The proposed method has been transferred to quality control laboratories to access the impurity profile during product storage.


Assuntos
Contaminação de Medicamentos , Fosfatos , Estabilidade de Medicamentos , Suspensões , Betametasona , Cromatografia Líquida de Alta Pressão/métodos
3.
J Biomol Struct Dyn ; 40(5): 2316-2326, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33107782

RESUMO

In the present study, 4-[(E)-(2-chorobenzylidene)amino]-3-(2-chlorobenzyl)-1H-1,2,4-triazole-5(4H)-thione (CAC) was characterized by spectroscopic investigations. The complete vibrational assignments of frequencies based on PED analysis was determined by DFT through ωB97X-D method with the level of 6-31g(d) basis and compared with experimental values. Recently nanocluster based drug delivery systems have become the most skilful to study. Interaction mechanism of CAC over coronene (G), doped CAC-G-X (X = B/N/P) and with graphene were investigated. Variations in chemical descriptors are also noted to understand sensing property of CAC molecule-nanoclusters. The analysis of different properties demonstrates enhancement effect which makes it significant in detecting CAC in other products. Molecular electrostatic potential energy surface was employed to investigate the most reactive sites. Besides to gain better insight on structural features, HOMO-LUMO band gap energy and other chemical parameters was obtained. The anticancer activity of CAC against various inhibitors for different protein targets (4AT9, 6NE5, 5ZBQ, and 3A43) was studied using molecular docking.Communicated by Ramaswamy H. Sarma.


Assuntos
Grafite , Teoria Quântica , Domínio Catalítico , Modelos Moleculares , Simulação de Acoplamento Molecular , Compostos Policíclicos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Triazóis/química
4.
Ann Pharm Fr ; 80(1): 35-47, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34153240

RESUMO

The basic objective of this study is to propose a short, reliable, mass compatible ultra-performance liquid chromatography (UPLC) method to confirm the identity of impurities and to estimate the assay and purity of Tirofiban simultaneously in aqueous injection (5mg/100mL bag). Aqueous formulations are susceptible to oxidation, hence the possible oxidative degradation impurities of Tirofiban were studied in this experiment by using UPLC coupled with photodiode array/Quadrupole Dalton Analyzer (PDA/QDa) detectors. The required separations were achieved in the column: ACQUITY HSS T3 (100×2.1) mm, 1.7µm, operated at 30°C by using 0.02% Triethyl amine (TEA) in water, pH 2.8 with formic acid as solution-A and 0.1% formic acid in 9:1 acetonitrile, water as solution-B. Binary gradient flow is delivered at the rate of 0.5mL/min and the detection of impurities specifically carried out at 227nm using empower3 software. RP-UPLC/PDA with QDa detector was used for the experiment. The method was linear and accurate from the concentrations: 0.04 to 0.38µg/mL for impurity-A and 0.04 to 75µg/mL for Tirofiban. The major unknown degradation impurity generated during the oxidative degradation has been identified as N-oxide derivative (Impurity-B) [(M+H)+ 455.1] by using QDa detector operated in an electro spray positive ion mode by applying a voltage of 0.8kV. This method was further validated as per ICH Q2 (R2) guidelines. Hence, the proposed method is said to be a fast, sensitive and comprehensive technique, which could give a clear idea about the assay and impurity profile of Tirofiban injection.


Assuntos
Estresse Oxidativo , Água , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Tirofibana
5.
Heliyon ; 7(7): e07634, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34381897

RESUMO

The research received a great deal of worldwide attention due to the nature of interpretation before the experimental process. Based on the systematic process the structure of thiazole -pyrazole compound 4-[{2-[3-(4-chlorophenyl)-5-(4-propan-2-yl) phenyl)-4, 5-dihydro- 1H- pyrazol-1-yl]-4-oxo-1, 3- thiazol-5(4H)-ylidene} methyl] benzonitrile [CPTBN] was investigated. In the first level, the spectral statistics on experimental FT-IR and FT- Raman was reported. At the next level, geometrical parameters was theoretically acquired from density functional theory (DFT) using B3LPY/6-31G and 6-311G basis set. The computed Wavenumber were collected and compared with the experimental data. The vibrational modes were interpreted in terms of potential energy distribution (PED) results. The FMO, MEP, and NBO analysis further validated the electrophilic and nucleophilic interaction in the molecular systems. Two grams-positive bacteria: staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria: Esherichia coli, Pseudomonas aeruginosa was performed for antibacterial activity. Two fungal strain Candida albicans and Aspergillus Niger was carried out against a ligand using anti-fungal activity. The molecular docking analysis explores the antimicrobial and selective potential inhibitory nature of the binding molecule. Besides, RDG and ELF analysis were also performed to show the nature of interactions between the molecule.

6.
Appl Radiat Isot ; 166: 109390, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33091858

RESUMO

Tritium in the form of tritiated water is easily incorporated into terrestrial biota as tissue free water tritium (TFWT). A part of TFWT is converted into organically bound tritium (OBT) through metabolic processes. For the computation of NE-OBT activity (expressed as Bq L-1 of combustion water) in terrestrial plants, knowledge on 'water equivalent factor (WEQp)', defined as the volume of water produced from the combustion of 1 kg of the dry sample, is essential. On a global scenario, experimental data are not available on this parameter. This paper presents (i) a method for determination of WEQp by combustion method using a tube furnace system, (ii) a large database (N = 294) on WEQp parameter for samples of tropical monsoonal climate region of the Indian subcontinent, and (iii) NE-OBT activity in terrestrial biota samples (N = 186) collected from the vicinity of a PHWR nuclear power plant of India. The data generated in this study on WEQp serves for the validation of the data compiled in IAEA (2009 and 2010), which are estimated based on the hydrogen content of protein, fat and carbohydrates, and the fractions of protein, fat and carbohydrates. The WEQp varied in the ranges of 0.492-0.678 L kg-1 (GM = 0.569 Bq L-1, GSD = 1.06), 0.520-0.630 L kg-1 (GM = 0.557 Bq L-1, GSD = 1.02) 0.473-0.633 L kg-1 (GM = 0.562 Bq L-1, GSD = 1.02) for non-leafy vegetables, leafy vegetables, and fruits, respectively. A comparison between the experimental WEQp data with those compiled in the IAEA report revealed that the maximum deviation between the two data sets is <10%. The NE-OBT activity in the food samples collected from 2.3 to 20 km zone around NPP had a geometric mean (GM) value of 25.4 Bq L-1 (GSD = 1.6, N = 186). Variations in NE-OBT activity with different seasons of the year are discussed.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117609, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31622823

RESUMO

In this present work, a molecule (2E)-3-(biphenyl-4-yl)-1-(4-bromophenyl) prop-2-en-1-one (3BPO) was synthesized and the structure has been characterized by using spectroscopic techniques. The most stable conformational structure of title compound has been calculated using HF-6-31G(d,p) basis set. DFT method were used through B3LYP/6-311++G(d,p) basis set to optimize the structure of the title compound. The geometrical parameters, vibrational wavenumbers and electronic properties have also been performed. The electronic properties for HOMO-LUMO, UV-Vis and MEP maps were contemplated by IEFPCM model with various solvation impacts which depends on TD-DFT ((M062X for UV and B3LYP for HOMO-LUMO, MEP)/6-311++G(d,p)) strategies. The NLO activity of title compound has been examined by solvation DFT/B3LYP technique with 6-311++G(d,p) premise set. Mean while, lone pair of donor-acceptor interactions and H bond donor/acceptor surface has been obtained by which a charge transfer mechanism can be explained. Molecular docking has been explored to comprehend the coupling transportation of the examined ligand with human folate receptor alpha in complex with folic corrosive protein (4LRH).

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117190, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31177006

RESUMO

Chalcone derivative of (2E)­1­(3­bromo­2­thienyl)­3­(2,5­dimethoxyphenyl) prop­2­en­1­one (BTD) molecule has been deliberated for spectroscopic properties experimentally and theoretically. The title compound was characterized by FT-IR, FT-Raman and UV-Vis analyses. The structural activity and vibrational wavenumbers were calculated by a DFT method. The Natural Bond Orbital (NBO) analysis which reveals the hyper conjugative interactions of the present molecule has been performed. Meanwhile, the Chemical reactivity of Condensed Fukui function, MEP and HOMO-LUMO energies of the molecule were also analyzed. Furthermore, Multiwfn 3.3.9 program has been utilized to study MEP and the electron excitation analysis. Docking studies which play a significant role in determining the endothelial nitric oxide synthase inhibition activity of the present compound have also been carried out to predict the binding energy and inhibition constant of the title compound. In addition, drug resemblance parameters have also considered by QSAR study in which the comparison of chemical parameters of chalcone drugs of title molecule has been done.


Assuntos
Chalconas/química , Chalconas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Animais , Bovinos , Halogenação , Simulação de Acoplamento Molecular , Óxido Nítrico Sintase Tipo III/metabolismo , Relação Quantitativa Estrutura-Atividade , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica
9.
Int J Microbiol ; 2018: 5916712, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29955230

RESUMO

Soft contact lenses provide perfect conditions for the breeding of pathogens. The study is a prospective, experimental study, conducted to know the antimicrobial ability of multipurpose contact lens solution against standard strains of Staphylococcus aureus and Pseudomonas aeruginosa by the stand-alone test. The test method is based on the procedures in the ISO 14729 standard primary stand-alone test. Three multipurpose contact lens care solutions commercially available in Mangalore markets, namely, Biotrue (Bausch & Lomb), Opti-Free Replenish (Alcon), and Aquasoft (Stericon Pharma), were tested for its antimicrobial effect in the microbiology lab at Kasturba Medical College, Mangalore. According to this study, the solutions named "Biotrue" and "Aquasoft" met the primary stand-alone and reached the 3log reduction and 5log reduction criteria in the manufacturer recommended time, respectively. No conclusion could be drawn for Opti-Free Replenish since the minimum recommended disinfection time was overnight, whereas it was noted for 6 hr only, and it should have been experimented further. The effectiveness of multipurpose solutions varies against different bacterial species. We have observed that the antimicrobial activity of different solutions varies with respect to time of incubation, and also there was a marked difference in the activity of some solutions against S. aureus and P. aeruginosa. So, it is necessary for the contact lens users to store their lenses in solutions for longer duration of hours. It is also recommended to use solutions that clear the ISO 14729 standards for better health conditions of the eye.

10.
Artigo em Inglês | MEDLINE | ID: mdl-28898821

RESUMO

Experimental FT-IR and FT-Raman spectra of 2-methylphenylacetic acid (MPA) were recorded and theoretical values are also analyzed. The non-linear optical (NLO) properties were evaluated by determination of first (5.5053×10-30 e.s.u.) and second hyper-polarizabilities (7.6833×10-36 e.s.u.) of the title compound. The Multiwfn package is used to find the weak non-covalent interaction (Van der Wall interaction) and strong repulsion (steric effect) of the molecule and examined by reduced density gradient. The molecular electrostatic potential (MEP) analysis used to find the most reactive sites for the electrophilic and nucleophilic attack. The chemical activity (electronegativity, hardness, chemical softness and chemical potential) of the title compound was predicted with the help of HOMO-LUMO energy values. The natural bond orbital (NBO) has been analyzed the stability of the molecule arising from the hyper-conjugative interaction. DSSCs were discussed in structural modifications that improve the electron injection efficiency of the title compound (MPA). The Fukui functions are calculated in order to get information associated with the local reactivity properties of the title compound. The binding sites of the two receptors were reported by molecular docking field and active site bond distance is same 1.9Å. The inhibitor of the title compound forms a stable complex with 1QYV and 2H1K proteins at the binding energies are -5.38 and -5.85 (∆G in kcal/mol).


Assuntos
Elétrons , Modelos Moleculares , Simulação de Acoplamento Molecular , Fenilacetatos/química , Energia Solar , Vibração , Domínio Catalítico , Humanos , Ligantes , Conformação Molecular , Dinâmica não Linear , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termodinâmica
11.
J Environ Manage ; 206: 69-76, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29059573

RESUMO

Sulfate ions pose a major threat and challenge in the treatment of industrial effluents. The sample of wastewater obtained from a pigment industry contained large quantities of sulfate in the form of sodium sulfate which resulted in high TDS. As the removal of sulfate from pigment industry effluent was not reported previously, this work was focused on removing the sulfate ions from the effluent by chemical precipitation using barium chloride. The efficiency of sulfate removal was nearly 100% at an excess dosage of barium chloride, which precipitates the dissolved sulfate ions in the form of barium sulfate. Optimization of the parameters was done using Response Surface Methodology (RSM). This work is the first attempt for modeling the removal of sulfate from pigment industry effluent using RSM and Artificial Neural Network (ANN). Prediction by both the models was evaluated and both of them exhibited good performance (R2 value > 0.99). It was observed that the prediction by RSM (R2 value 0.9986) was closer to the experimental results than ANN prediction (R2 value 0.9955). The influence on the pH and conductivity of the solution by dosage of precipitant was also studied. The formation of barium sulfate was confirmed by characterization of the precipitate. Therefore, the sulfate removed from the effluent was converted into a commercially valuable precipitate.


Assuntos
Compostos de Bário , Precipitação Química , Cloretos , Concentração de Íons de Hidrogênio , Sulfatos
12.
Appl Radiat Isot ; 125: 86-93, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28427043

RESUMO

In this work, the neutron radiation shielding characteristics of a class of novel polymer-incorporated self-compacting concrete (PISCC) mixes are evaluated. Pulverized high density polyethylene (HDPE) material was used, at three different reference volumes, as a partial replacement to river sand in conventional concrete mixes. By such partial replacement of sand with polymer, additional hydrogen contents are incorporated in these concrete mixes and their effect on the neutron radiation shielding properties are studied. It has been observed from the initial set of experiments that there is a definite trend of reductions in the neutron flux and dose transmission factor values in these PISCC mixes vis-à-vis ordinary concrete mix. Also, the fact that quite similar enhanced shielding results are recorded even when reprocessed HDPE material is used in lieu of the virgin HDPE attracts further attention.

13.
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
14.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 2): o123-4, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25878864

RESUMO

The asymmetric unit of the title compound, C9H7NO2S, contains two crystallographically independent mol-ecules (A and B). Both mol-ecules are almost planar [maximum deviations = 0.047 (1) and 0.090 (1) Å, respectively, for the S atoms] with the oxazole and thio-phene rings being inclined to one another by 2.65 (16)° in mol-ecule A and by 4.55 (15)° in mol-ecule B. In the crystal, the individual mol-ecules are linked via C-H⋯O hydrogen bonds, forming -A-B-A-B- chains along the [10-1] direction. The chains are linked via C-H⋯π and π-π inter-actions [inter-centroid distances = 3.767 (2) and 3.867 (2) Å] involving inversion-related oxazole and thio-phene rings in both mol-ecules, forming a three-dimensional structure.

15.
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
16.
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
17.
Artigo em Inglês | MEDLINE | ID: mdl-25062053

RESUMO

(2E)-1-(2,4-Dichlorophenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one is synthesized by using 2,4-dichloroacetophenone and 3,4,5-trimethoxybenzaldehyde in ethanol. The structure of the compound was confirmed by IR and single crystal X-ray diffraction studies. FT-IR spectrum of (2E)-1-(2,4-dichloro-phenyl)-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one was recorded and analyzed. The crystal structure is also described. The vibrational wavenumbers were computed using HF and DFT methods and are assigned with the help of potential energy distribution method. The first hyperpolarizability and infrared intensities are also reported. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The HOMO and LUMO analysis are used to determine the charge transfer within the molecule. MEP was performed by the DFT method. From the MEP map of the title molecule, negative region is mainly localized over the electronegative oxygen atoms, in the carbonyl group and the oxygen atom O4 of the methoxy group and the maximum positive region is localized on the phenyl rings.


Assuntos
Derivados de Benzeno/química , Elétrons , Hidrocarbonetos Clorados/química , Modelos Moleculares , Propano/análogos & derivados , Teoria Quântica , Eletricidade Estática , Cristalografia por Raios X , Conformação Molecular , Dinâmica não Linear , Fenômenos Ópticos , Propano/química , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 162-71, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25062062

RESUMO

FT-IR spectrum of 1-(10H-phenothiazin-2-yl)ethanone was recorded and analyzed. The equilibrium geometry, bonding features and harmonic vibrational wavenumbers were investigated with the help of HF and DFT methods. The normal modes are assigned with the help of potential energy distribution analysis. The observed vibrational wavenumbers were compared with the calculated results. The geometrical parameters of the title compound obtained from XRD studies are in agreement with the calculated (DFT) values. The first hyperpolarizability value is also reported. Natural bond orbital analysis confirms the presence of intra-molecular charge transfer and hydrogen bonding interaction. The HOMO-LUMO gap explains the charge transfer interaction taking place within the molecule. The N-H stretching frequency is red shifted in the IR spectrum with a strong intensity from the computed frequency, which indicates weakening of the N-H bond resulting in proton transfer to the neighboring units. From the MEP analysis it is evident that the negative charge covers the carbonyl and benzene and the positive region is over the NH group.


Assuntos
Elétrons , Modelos Moleculares , Fenotiazinas/química , Teoria Quântica , Eletricidade Estática , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Vibração
19.
Artigo em Inglês | MEDLINE | ID: mdl-25463053

RESUMO

The optimized molecular structure, vibrational frequencies, corresponding vibrational assignments of ethyl-6-(4-chlorophenyl)-4-(4-fluoro-phenyl)-2-oxocyclohex-3-ene-1-carboxylate have been investigated experimentally and theoretically using Gaussian09 software. The title compound was optimized using the HF and DFT levels of theory. The geometrical parameters are in agreement with the XRD data. The stability of the molecule has been analyzed by NBO analysis. The HOMO and LUMO analysis is used to determine the charge transfer within the molecule. Molecular electrostatic potential was performed by the DFT method. As can be seen from the MEP map of the title compound, regions having the negative potential are over the electro negative atoms, the region having the positive potential are over the phenyl rings and the remaining species are surrounded by zero potential. First hyperpolarizability is calculated in order to find its role in non linear optics. The title compound binds at the active sites of both CypD and ß-secretase and the molecular docking results draw the conclusion that the compound might exhibit ß-secretase inhibitory activity which could be utilized for development of new anti-alzheimeric drugs with mild CypD inhibitory activity.


Assuntos
Ácidos Carboxílicos/química , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácidos Carboxílicos/farmacologia , Descoberta de Drogas , Halogenação , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
20.
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
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