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2.
BMC Chem ; 18(1): 102, 2024 May 21.
Article de Anglais | MEDLINE | ID: mdl-38773663

RÉSUMÉ

BACKGROUND: Carbazole-based molecules containing thiosemicarbazide functional groups are recognized for their diverse biological activities, particularly in enhancing therapeutic anticancer effects through inhibiting crucial pathways. These derivatives also exhibit noteworthy antioxidant properties. OBJECTIVES: This study aims to synthesize, characterize, and evaluate the antioxidant and anticancer activities of 18 novel carbazole derivatives. METHODS: The radical scavenging capabilities of the compounds were assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. Antiproliferative activities were evaluated on MCF-7 cancer cell lines through viability assays. Additionally, the modulation of the PI3K/Akt/mTOR pathway, apoptosis/necrosis induction, and cell cycle analysis were conducted for the most promising anticancer agents. RESULTS: nine compounds showed potent antioxidant activities with IC50 values lower than the positive control acarbose, with compounds 4 h and 4y exhibiting the highest potency (IC50 values of 0.73 and 0.38 µM, respectively). Furthermore, compounds 4o and 4r displayed significant anticancer effects, with IC50 values of 2.02 and 4.99 µM, respectively. Compound 4o, in particular, exhibited promising activity by targeting the PI3K/Akt/mTOR signaling pathway, inhibiting tumor survival, inducing apoptosis, and causing cell cycle arrest in MCF-7 cell lines. Furthermore, compound 4o was showed significant antimicrobial activities against S. aureus and E. coli, and antifungal effect against C. albicans. Its potential to overcome drug resistance through this pathway inhibition highlights its promise as an anticancer agent. Molecular docking simulations supported these findings, revealing favorable binding profiles and interactions within the active sites of the enzymes PI3K, AKT1, and mTOR. Moreover, assessing the druggability of the newly synthesized thiosemicarbazide derivatives demonstrated optimal physicochemical properties, further endorsing their potential as drug candidates.

3.
Arch Pharm (Weinheim) ; 357(8): e2300634, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38772694

RÉSUMÉ

Novel synthesized pyrimidine derivatives were investigated against carbonic anhydrase isoenzymes I and II (hCA I and II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-glycosidase, and aldose reductase (AR) enzymes associated with some common diseases such as epilepsy, glaucoma, Alzheimer's disease, diabetes, and neuropathy. When the results were examined, novel synthesized pyrimidine derivatives were found to have effective inhibition abilities toward the metabolic enzymes. IC50 values and Ki values were calculated for each pyrimidine derivative and compared to positive controls. The synthesized novel pyrimidine derivatives exhibited Ki values in the range of 39.16 ± 7.70-144.62 ± 26.98 nM against hCA I, 18.21 ± 3.66-136.35 ± 21.48 nM toward hCA II, which is associated with different pathological and physiological processes, 33.15 ± 4.85-52.98 ± 19.86 nM on AChE, and 31.96 ± 8.24-69.57 ± 21.27 nM on BChE. Also, Ki values were determined in the range of 17.37 ± 1.11-253.88 ± 39.91 nM against α-glycosidase and 648.82 ± 53.74-1902.58 ± 98.90 nM toward AR enzymes. Within the scope of the study, the inhibition types of the novel synthesized pyrimidine derivatives were evaluated.


Sujet(s)
Acetylcholinesterase , Butyrylcholine esterase , Pyrimidines , Pyrimidines/pharmacologie , Pyrimidines/synthèse chimique , Pyrimidines/composition chimique , Relation structure-activité , Acetylcholinesterase/métabolisme , Butyrylcholine esterase/métabolisme , Humains , Inhibiteurs de l'anhydrase carbonique/pharmacologie , Inhibiteurs de l'anhydrase carbonique/synthèse chimique , Inhibiteurs de l'anhydrase carbonique/composition chimique , Anticholinestérasiques/pharmacologie , Anticholinestérasiques/synthèse chimique , Anticholinestérasiques/composition chimique , Structure moléculaire , Aldose reductase/antagonistes et inhibiteurs , Aldose reductase/métabolisme , Carbonic anhydrase I/antagonistes et inhibiteurs , Carbonic anhydrase I/métabolisme , Relation dose-effet des médicaments , Carbonic anhydrase II/antagonistes et inhibiteurs , Carbonic anhydrase II/métabolisme , Concentration inhibitrice 50
4.
Mol Neurobiol ; 61(7): 4565-4576, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38105408

RÉSUMÉ

In the 1980s, the identification of specific pharmacological antagonists played a crucial role in enhancing our comprehension of the physiological mechanisms associated with α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPARs). The primary objective of this investigation was to identify specific AMPA receptor antagonists, namely 2,3-benzodiazepines, that function as negative allosteric modulators (NAMs) at distinct locations apart from the glutamate recognition site. These compounds have exhibited a diverse array of anticonvulsant properties. In order to conduct a more comprehensive investigation, the study utilized whole-cell patch-clamp electrophysiology to analyze the inhibitory effect and selectivity of benzodiazepine derivatives that incorporate coumarin rings in relation to AMPA receptors. The study's main objective was to acquire knowledge about the relationship between the structure and activity of the compound and comprehend the potential effects of altering the side chains on negative allosteric modulation. The investigation provided crucial insights into the interaction between eight CD compounds and AMPA receptor subunits. Although all compounds demonstrated effective blockade, CD8 demonstrated the greatest potency and selectivity towards AMPA receptor subunits. The deactivation and desensitization rates were significantly influenced by CD8, CD6, and CD5, distinguishing them from the remaining five chemicals. The differences in binding and inhibition of AMPA receptor subunits can be attributed to structural discrepancies among the compounds. The carboxyl group of CD8, situated at the para position of the phenyl ring, substantially influenced the augmentation of AMPA receptor affinity. The findings of this study highlight the potential of pharmaceutical compounds that specifically target AMPA receptors to facilitate negative allosteric modulation.


Sujet(s)
Benzodiazépines , Coumarines , Ouverture et fermeture des portes des canaux ioniques , Récepteur de l'AMPA , Récepteur de l'AMPA/métabolisme , Récepteur de l'AMPA/antagonistes et inhibiteurs , Benzodiazépines/pharmacologie , Benzodiazépines/composition chimique , Ouverture et fermeture des portes des canaux ioniques/effets des médicaments et des substances chimiques , Coumarines/pharmacologie , Coumarines/composition chimique , Humains , Animaux , Cellules HEK293 , Phénomènes biophysiques
5.
BMC Chem ; 17(1): 60, 2023 Jun 16.
Article de Anglais | MEDLINE | ID: mdl-37328860

RÉSUMÉ

BACKGROUND: The carbazole skeleton is an important structural motif occurring naturally or synthesized chemically and has antihistaminic, antioxidant, antitumor, antimicrobial, and anti-inflammatory activities. OBJECTIVES: This study aimed to design and synthesize a novel series of carbazole derivatives and evaluate their antiproliferative and antioxidant activities. METHODS: The synthesized compounds were characterized utilizing HRMS, 1H-, and 13CAPT-NMR, and assessed for their anticancer, antifibrotic, and antioxidant effects utilizing reference biomedical procedures. In addition, the AutoDock Vina application was used to perform in-silico docking computations. RESULTS: A series of carbazole derivatives were synthesized and characterized in the current study. Compounds 10 and 11 were found to have a stronger antiproliferative effect than compounds 2-5 against HepG2, HeLa, and MCF7 cancer cell lines with IC50 values of 7.68, 10.09, and 6.44 µM, respectively. Moreover, compound 9 showed potent antiproliferative activity against HeLa cancer cell lines with an IC50 value of 7.59 µM. However, except for compound 5, all of the synthesized compounds showed moderate antiproliferative activities against CaCo-2 with IC50 values in the range of 43.7-187.23 µM. All of these values were compared with the positive control anticancer drug 5-Fluorouracil (5-FU). In addition, compound 9 showed the most potent anti-fibrotic compound, and the cellular viability of LX-2 was found 57.96% at 1 µM concentration in comparison with the positive control 5-FU. Moreover, 4 and 9 compounds showed potent antioxidant activities with IC50 values of 1.05 ± 0.77 and 5.15 ± 1.01 µM, respectively. CONCLUSION: Most of the synthesized carbazole derivatives showed promising antiproliferative, antioxidant, and antifibrotic biological effects, and further in-vivo investigations are needed to approve or disapprove these results.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122516, 2023 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-36868025

RÉSUMÉ

This study represents detailed vibrational analysis of naphthalene bisbenzimidazole (NBBI), perylene bisbenzimidazole (PBBI), and naphthalene imidazole (NI) by vibrational spectroscopic (Fourier Transform Infrared (FT-IR) and Raman), Atomic Force Microscopic (AFM) and quantum chemical studies for the first time. These sorts of compounds provide an opportunity to build potential n-type organic thin film phototransistors which can be used as organic semiconductors. Optimized molecular structures and vibrational wavenumbers of these molecules in their ground states have been calculated by Density Functional Theory (DFT) using B3LYP functional with 6-311++G(d,p) basis set. Finally, theoretical UV-Visible spectrum was predicted and Light Harvesting Efficiencies (LHE) were evaluated. AFM analysis revealed that PBBI has the highest surface roughness thus exhibits an increase in high Jsc value and high conversion efficiency.

7.
J Biomol Struct Dyn ; 41(23): 14382-14397, 2023.
Article de Anglais | MEDLINE | ID: mdl-36826447

RÉSUMÉ

Intensive studies on hepatocellular carcinoma (HCC), which is spreading rapidly around the world and has a high mortality rate, is due to the lack of adequate preventive or curative treatment methods. Treating patients with HCC has become very challenging because of the heterogeneity in the patient population lead activation of different signaling pathways, and pathway crosstalk for patients. Therefore, understanding these molecular mechanisms and combining drugs with molecular therapies to overcome these drawbacks has become an area of utmost importance. In this study, the biological activities of the designed and characterized triad Pyrazole-Thiazol-Coumarin (PTC) compounds were determined by performing cell viability, qPCR array, apoptosis and cell cycle assays. One of the compounds (PTC10) implicitly suppresses multiple pathways (RAS/MAP kinase and PI3K-AKT) simultaneously. This action is provided by (i) arresting cancer cells at G2 phase, (ii) driving cancer cells to apoptosis and (iii) inhibiting HSP network. Remarkably, HSP is an apoptotic factor and help cancer cell to survive. HSP90 also coordinates with Cdk4/Cdc37, therefore inhibiting HSP both drives cells to arrest and apoptosis. ATP hydrolysis and aggregation assay further displayed specific HSP inhibition. Therefore, PTC provides a unique drug template for HCC treatment.


Sujet(s)
Antinéoplasiques , Carcinome hépatocellulaire , Tumeurs du foie , Humains , Carcinome hépatocellulaire/traitement médicamenteux , Tumeurs du foie/traitement médicamenteux , Phosphatidylinositol 3-kinases/métabolisme , Phosphatidylinositol 3-kinases/pharmacologie , Phosphatidylinositol 3-kinases/usage thérapeutique , Thiazoles/pharmacologie , Pyrazoles/pharmacologie , Apoptose , Coumarines/pharmacologie , Prolifération cellulaire , Lignée cellulaire tumorale , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique
8.
J Biomol Struct Dyn ; 41(21): 11578-11597, 2023.
Article de Anglais | MEDLINE | ID: mdl-36617972

RÉSUMÉ

In this work, a novel crystal, (E)-4-(4-methylbenzyl)-6-styrylpyridazin-3(2H)-one (E-BSP) was synthesized via Knoevenagel condensation of benzaldehyde and (E)-6-(4-methoxystyryl)-4,5-dihydropyridazin-3(2H)-one. The molecular structure of E-BSP was confirmed by using FT-IR, 1H-NMR, 13C-NMR, UV-vis, ESI-MS, TGA/DTA thermal analyses and single crystal X-ray diffraction. The DFT/B3LYP methods with the 6-311++G(d,p) basis set were used to determine the vibrational modes over the optimized structure. Potential energy distribution (PED) and the VEDA 4 software were used to establish the theoretical mode assignments. The same approach was used to compute the energies of frontier molecular orbitals (HOMO-LUMO), global reactivity descriptors, and molecular electrostatic potential (MEP). Additionally, experimental and computed UV spectral parameters were determined in methanol and the obtained outputs were supported by FMO analysis. Molecular docking and molecular dynamics (MD) simulation analyses of the E-BSP against six proteins obtained from different cancer pathways were carried out. The proteins include; epidermal growth factor receptor (EGFR), Estrogen receptor (ERα), Mammalian target of rapamycin (mTOR), Progesterone receptor (PR) (Breast cancer), Human cyclin-dependent kinase 2 (CDK2) (Colorectal cancer), and Survivin (Squamous cell carcinoma/Non-small cell lung cancer). The results of the analyses showed that the compound had less binding energies ranging between -6.30 to -9.09 kcal/mol and formed stable complexes at the substrate-binding site of the proteins after the 50 ns MD simulation. Therefore, E-BSP was considered a potential inhibitor of different cancer pathways and should be used for the treatment of cancer after experimental validation and clinical trial.Communicated by Ramaswamy H. Sarma.


Sujet(s)
Antinéoplasiques , Carcinome pulmonaire non à petites cellules , Tumeurs du poumon , Humains , Simulation de dynamique moléculaire , Simulation de docking moléculaire , Spectroscopie infrarouge à transformée de Fourier , Analyse spectrale Raman , Antinéoplasiques/pharmacologie
9.
J Biomol Struct Dyn ; 41(6): 2492-2503, 2023 04.
Article de Anglais | MEDLINE | ID: mdl-35132941

RÉSUMÉ

The hybrid molecules bearing heterocyclic structures in the A or D rings of steroids have significant biological activity. 16 (E)-Hetereoarylidene steroids were synthesized from the reaction of different heteroaromatic carbaldehydes and trans-Dehydroepiandrosterone (DHEA) in a basic medium. Then, synthesis of the N-formyl pyrazoline substituted new DHEA derivatives were carried out from the reaction of hydrazine hydrate and 16 (E)-hetereoarylidene steroids. The structures of the synthesized compounds were elucidated by elemental analysis, FT-IR, 1H NMR, and 13C NMR spectroscopy. To investigate the activation pathway of synthesized N-formyl pyrazoline substituted steroid derivatives, a molecular docking study was performed on human cytochrome P450-(CYP17A1: PDB ID 5IRQ) with the help of the free AutoDock Vina. 100 ns molecular dynamic simulation process was performed to monitor the behavior of the complex structure formed by CYP17A1 and to calculate the stability over time of 2a and 2d (-9.8 kcal/mol), which gave the lowest value according to the results obtained in the molecular docking study with AutoDock Vina. Accordingly, RMSD, RMSF, Rg, and SASA analyzes of 2a and 2d were performed, and MMPBSA was calculated. Lastly, the ADMET (absorption, distribution, metabolism, excretion, and toxicity) analyses of the novel steroid derivatives were investigated.Communicated by Ramaswamy H. Sarma.


Sujet(s)
Déhydroépiandrostérone , Simulation de dynamique moléculaire , Humains , Simulation de docking moléculaire , Spectroscopie infrarouge à transformée de Fourier
10.
Molecules ; 27(7)2022 Mar 28.
Article de Anglais | MEDLINE | ID: mdl-35408592

RÉSUMÉ

The title compound was synthesized and structurally characterized. Theoretical IR, NMR (with the GIAO technique), UV, and nonlinear optical properties (NLO) in four different solvents were calculated for the compound. The calculated HOMO-LUMO energies using time-dependent (TD) DFT revealed that charge transfer occurs within the molecule, and probable transitions in the four solvents were identified. The in silico absorption, distribution, metabolism, and excretion (ADME) analysis was performed in order to determine some physicochemical, lipophilicity, water solubility, pharmacokinetics, drug-likeness, and medicinal properties of the molecule. Finally, molecular docking calculation was performed, and the results were evaluated in detail.


Sujet(s)
Analyse spectrale Raman , Vibration , Hydrazines , Modèles moléculaires , Conformation moléculaire , Simulation de docking moléculaire , Théorie quantique , Solvants/composition chimique , Spectrophotométrie UV , Spectroscopie infrarouge à transformée de Fourier , Thermodynamique , Triazoles
11.
J Biomol Struct Dyn ; 40(19): 8655-8671, 2022.
Article de Anglais | MEDLINE | ID: mdl-33890547

RÉSUMÉ

A novel series of pyrrole-3-one derivatives were synthesized using furan-3-one derivatives and various aromatic amines. The synthesized compounds were identified by spectral studies such as IR, NMR and HRMS. Dielectric properties of the target compounds were experimentally determined by dielectric spectroscopy in the frequency range of 20 Hz - 1 MHz. The real part of the dielectric constant, dielectric loss tangent and conductivity of the samples were investigated as a function of applied frequency. Dielectric measurements showed Ata7 has the maximum dielectric constant at 1 kHz, while Ata1 has a negative dielectric constant value. When the result is evaluated with theoretical calculations, grain boundaries play an effective role in the experimental observed dielectric constant. Additionally, in this research the pyrrole-3-one derivatives (Ata1-9) were theoretically optimized and over these structures, NMR with GIAO (gauge-independent atomic orbital), UV with TD (time dependent), frontier orbitals (HOMO and LUMO), NLO (nonlinear optical properties) and MEP (molecular electrostatic potential) analysis were carried out. Quantum chemical computations were performed by Density Functional Theory (DFT) using B3LYP functional and 6-311++G (d,p) basis set. Later, the molecular docking analysis between Ata1-9 and two different receptors such as 3RZE and 3TDA was performed using AutoDock Vina program. Lastly, drug-likeness, physicochemical and ADME/T properties of the designed compounds were computed with the help of SwissADME online tool.Communicated by Ramaswamy H. Sarma.


Sujet(s)
Pyrroles , Analyse spectrale Raman , Simulation de docking moléculaire , Modèles moléculaires , Spectroscopie infrarouge à transformée de Fourier , Théorie quantique , Spectrophotométrie UV , Thermodynamique
12.
Arch Pharm (Weinheim) ; 355(1): e2100242, 2022 Jan.
Article de Anglais | MEDLINE | ID: mdl-34609760

RÉSUMÉ

Human carbonic anhydrase (hCA) isoenzymes are zinc ion-containing, widespread metalloenzymes and they classically play a role in pH homeostasis maintenance. CA inhibitors suppress the CA activity and their usage has been clinically established as antiglaucoma agents, antiepileptics, diuretics, and in some other disorders. Alzheimer's disease (AD) is a slowly progressive neurodegenerative disorder and a fatal disease of the brain. An advanced method to cure AD includes the strategy to design acetylcholinesterase (AChE) inhibitors. A novel series of pyrrole-3-one derivatives containing sulfa drugs (5a-i) were determined to be highly potent inhibitors for AChE and hCA I and hCA II (inhibitory constant [Ki ] values are in the range of 6.50 ± 1.02-37.46 ± 4.12 nM, 1.20 ± 0.19-44.21 ± 1.09 nM, and 8.93 ± 1.58-46.86 ± 8.41 nM for AChE, hCA I, and hCA II, respectively). The designed compounds often show a more effective inhibition than the chemicals used as the standard. Among these compounds, 5f was the most effective compound against hCA I, and compound 5e was the most effective compound against hCA II. It was determined that compound 5c was the most effective inhibitor for AChE.


Sujet(s)
Inhibiteurs de l'anhydrase carbonique/pharmacologie , Anticholinestérasiques/pharmacologie , Pyrroles/pharmacologie , Sulfonamides/pharmacologie , Carbonic anhydrase I/antagonistes et inhibiteurs , Carbonic anhydrase II/antagonistes et inhibiteurs , Inhibiteurs de l'anhydrase carbonique/synthèse chimique , Inhibiteurs de l'anhydrase carbonique/composition chimique , Anticholinestérasiques/synthèse chimique , Anticholinestérasiques/composition chimique , Humains , Isoenzymes , Pyrroles/synthèse chimique , Pyrroles/composition chimique , Relation structure-activité , Sulfonamides/synthèse chimique , Sulfonamides/composition chimique
13.
J Mol Struct ; 1232: 130005, 2021 May 15.
Article de Anglais | MEDLINE | ID: mdl-33526951

RÉSUMÉ

A potential new drug to treat SARS-CoV-2 infections and chloroquine analogue, 5-((1H-imidazol-1-yl)methyl)quinolin-8-ol (DD1) has been here synthesized and characterized by FT-IR, 1H-NMR, 13C-NMR, ultraviolet-visible, ESI-MS and single-crystal X-ray diffraction. DD1 was optimized in gas phase, aqueous and DMSO solutions using hybrid B3LYP/6-311++G(d,p) method. Comparisons between experimental and theoretical infrared spectra, 1H and 13C NMR chemical shifts and electronic spectrum in DMSO solution evidence good concordances. Higher solvation energy was observed in aqueous solution than in DMSO, showing in aqueous solution a higher value than antiviral brincidofovir and chloroquine. on Bond orders, atomic charges and topological studies suggest that imidazole ring play a very important role in the properties of DD1. NBO and AIM analyses support the intra-molecular O15-H16•••N17 bonds of DD1 in the three media. Low gap value supports the higher reactivity of DD1 than chloroquine justified by the higher electrophilicity and low nucleophilicity. Complete vibrational assignments of DD1 in gas phase and aqueous solution are reported together with the scaled force constants. In addition, better intermolecular interactions were observed by Hirshfeld surface analysis. Finally, the molecular docking mechanism between DD1 ligand and COVID-19/6WCF and COVID-19/6Y84 receptors were studied to explore the binding modes of these compounds at the active sites. Molecular docking results have shown that the DD1 molecule can be considered as a potential agent against COVID-19/6Y84-6WCF receptors.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 142: 169-77, 2015 May 05.
Article de Anglais | MEDLINE | ID: mdl-25703361

RÉSUMÉ

In this study, theoretical harmonic vibrational frequencies and geometric parameters of N-(4-methoxybenzoyl)-2-methylbenzenesulfonamide have been investigated by Hartree-Fock (HF), density functional theory (B3LYP hybrid functional) methods with 6-311++G (d,p) basis set, for the first time. Experimental FT-IR (400-4000cm(-1)) and Laser-Raman spectra (100-4000cm(-1)) of title compound in solid phase have been recorded. Interaction energies, N-H⋯O hydrogen bonds, C-H⋯O and aromatic π⋯π stacking interactions in dimer structures of the title compound have been evaluated by the calculation methods. The dimer calculations have aimed to present the efficacy and performance of M06-2X hybrid functional on the intermolecular interactions and more strongly bound systems for the corrected and interaction energy by the counterpoise correction procedure. The interaction energies by M06-2X approach give more stable results than HF and B3LYP, extremely. The more strongly bonds, especially, on N-H⋯O hydrogen bonds and π⋯π interaction for the both dimer structure have also supported that the M06-2X functional of density functional is more effective.


Sujet(s)
Dérivés du benzène/composition chimique , Sulfonamides/composition chimique , Dimérisation , Liaison hydrogène , Modèles moléculaires , Théorie quantique , Spectroscopie infrarouge à transformée de Fourier , Analyse spectrale Raman
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 145-55, 2015 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-25554964

RÉSUMÉ

In this study the experimental and theoretical vibrational frequencies of a newly synthesized anti-tumor, antiviral, hypoglycemic, antifungal and anti-HIV agent namely, 5-Methyl-3-phenylisoxazole-4-carboxylic acid has been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths, bond angles and torsion angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr and DFT/M06-2X: highly parametrized, empirical exchange correlation function) with 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated by using the same theoretical calculations.


Sujet(s)
Isoxazoles/composition chimique , Lasers , Modèles moléculaires , Analyse spectrale Raman , Électrons , Conformation moléculaire , Spectroscopie infrarouge à transformée de Fourier , Vibration
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 135: 137-46, 2015 Jan 25.
Article de Anglais | MEDLINE | ID: mdl-25062059

RÉSUMÉ

In present study, the experimental and theoretical harmonic vibrational frequencies of gliclazide molecule have been investigated. The experimental FT-IR (400-4000 cm(-1)) and Laser-Raman spectra (100-4000 cm(-1)) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) have been calculated using ab initio Hartree Fock (HF), density functional theory (B3LYP hybrid function) methods with 6-311++G(d,p) and 6-31G(d,p) basis sets by Gaussian 09W program. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. Theoretical optimized geometric parameters and vibrational frequencies have been compared with the corresponding experimental data, and they have been shown to be in a good agreement with each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies have been found.


Sujet(s)
Gliclazide/composition chimique , Hypoglycémiants/composition chimique , Modèles moléculaires , Théorie quantique , Vibration , Électrons , Conformation moléculaire , Spectroscopie infrarouge à transformée de Fourier , Analyse spectrale Raman , Thermodynamique
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 131: 502-11, 2014 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-24840492

RÉSUMÉ

The spectroscopic properties of (E)-3-(4-bromo-5-methylthiophen-2-yl)acrylonitrile have been investigated by FT-IR, UV, (1)H and (13)C NMR techniques. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and angles) have been calculated using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and DFT/M06-2X (the highly parameterized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 03 software, for the first time. The assignments of the vibrational frequencies have been carried out by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies were in good agreement with the corresponding experimental data, and with the results in the literature. (1)H and (13)C NMR chemical shifts were calculated by using the gauge-invariant atomic orbital (GIAO) method. The electronic properties, such as excitation energies, oscillator strength wavelengths were performed by B3LYP methods. In addition, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and the other related molecular energy values have been calculated and depicted.


Sujet(s)
Acrylonitrile/composition chimique , Thiophènes/composition chimique , Halogénation , Spectroscopie par résonance magnétique , Méthylation , Modèles moléculaires , Théorie quantique , Logiciel , Spectrophotométrie UV , Spectroscopie infrarouge à transformée de Fourier
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 130: 96-104, 2014 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-24769362

RÉSUMÉ

The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of ethyl (2E)-2-cyano-3-(4-methoxyphenyl)-acrylate in solid phase have been recorded. Its theoretical vibrational frequencies, IR intensities, Raman activities and optimized geometric parameters (bond lengths and bond angles) have been calculated using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr and DFT/M06-2X: the highly parameterized empirical exchange correlation function) with 6-311++G(d, p) basis set by Gaussian 03 software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis using VEDA4 software. The optimized geometric parameters and vibrational frequencies have been seen to be in good agreement with the corresponding experimental data and results in the literature. In addition, the highest occupied molecular orbital (HOMO) energy, the lowest unoccupied molecular orbital (LUMO) energy and the other related molecular energy values of the compound have been investigated by using the same theoretical calculations.


Sujet(s)
Acrylates/composition chimique , Cyanoacrylates/composition chimique , Lasers , Spectroscopie infrarouge à transformée de Fourier , Analyse spectrale Raman , Cristallographie aux rayons X , Modèles moléculaires , Conformation moléculaire , Loi normale , Théorie quantique , Logiciel , Vibration , Rayons X
19.
Article de Anglais | MEDLINE | ID: mdl-24657467

RÉSUMÉ

In this study, the experimental and theoretical vibrational frequencies of a newly synthesized tert-Butyl N-(thiophen-2yl)carbamate have been investigated. The experimental FT-IR (4000-400 cm(-1)) spectrum of the molecule in the solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and DFT/M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with the 6-311++G(d,p) basis set by Gaussian 09W software, for the first time. The vibrational frequencies have been assigned using potential energy distribution (PED) analysis by using VEDA 4 software. The computational optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data, and with related literature results. In addition, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and the other related molecular energy values have been calculated and are depicted.


Sujet(s)
Carbamates/composition chimique , Modèles moléculaires , Logiciel
20.
Article de Anglais | MEDLINE | ID: mdl-24662757

RÉSUMÉ

In this study, the experimental and theoretical vibrational spectral analysis of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone have been carried out. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) have been recorded for the solid state samples. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths and angles) have been calculated for gas phase using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set. The diversity in molecular geometry of fluorophenyl substituted thiosemicarbazones has been discussed based on the X-ray crystal structure reports and theoretical calculation results from the literature. The assignments of the vibrational frequencies have been done on the basis of potential energy distribution (PED) analysis by using VEDA4 software. A good correlation was found between the computed and experimental geometric and vibrational data. In addition, the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbital energy levels and other related molecular energy values of the compound have been determined using the same level of theoretical calculations.


Sujet(s)
Hydrocarbures fluorés/composition chimique , Modèles moléculaires , Logiciel , Thiosemicarbazones/composition chimique , Structure moléculaire , Spectroscopie infrarouge à transformée de Fourier/méthodes , Analyse spectrale Raman/méthodes
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