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1.
ACS Omega ; 9(7): 7424-7438, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405509

RESUMO

In this study, we report the synthesis of a new compound, N4,N4-dimethyl-2-(methylsulfanyl)-N6-(4-phenoxyphenyl)pyrimidine-4,6-diamine (DMS), and its comprehensive analysis through structural and spectroscopic characterizations, reactivity parameters, and nonlinear optical properties, utilizing a combination of experimental and computational techniques. The experimental aspect of the investigation encompassed structural characterization using X-ray diffraction and spectroscopic assessments employing Fourier-transform infrared, Raman, and nuclear magnetic resonance techniques, along with thermal analysis. Our computational approach involved density functional theory (DFT) calculations and molecular dynamics (MD) simulations to examine the local reactivity properties of DMS. We employed fundamental reactivity descriptors to evaluate DMS's local reactivity and utilized MD simulations to identify DMS atoms engaging in significant interactions with water molecules. We conducted periodic DFT calculations on DMS's crystal structure to investigate the contributions of specific atoms and groups to the compound's overall stability as well as to analyze noncovalent interactions between DMS molecules. We assessed the nonlinear optical properties through dynamic second hyperpolarizability and third-order nonlinear susceptibility calculations. Additionally, we conducted a comparative analysis of the static and dynamic second hyperpolarizability for the DMS molecule within the sum-over-states framework. The obtained value for the third-order nonlinear susceptibility, (λ = 1907 nm), exceeds those of other organic materials reported in previous studies, indicating that the DMS crystal holds promise as a nonlinear optical material for potential application in photonic device fabrication. Furthermore, molecular docking studies were performed with the 3E5A, 4EUT, and 4EUU proteins, yielding binding affinities of -8.1, -8.2, and -8.3 kcal/mol, respectively, in association with the ligand.

2.
J Mol Struct ; 1281: 135110, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-36785704

RESUMO

Developing modifiable natural products those having antiviral activities against SARS-CoV-2 is a key research area which is popular in current scenario of COVID pandemic. A diaryl heptanoid curcumin and its derivatives are already presenting promising candidates for anti-viral drug development. We have synthesized single crystals of a dimethylamino derivative of natural curcumin and structural characterization was done by single crystal XRD analysis. Using steady-state absorption and emission spectra and guided by complimentary ab initio calculations, we unraveled the solvent effects on the photophysical properties of the dimethyl amino curcumin derivative. Chemical reactivity of the compound has investigated using frontier molecular orbitals and molecular electrostatic potential surface. High stability of the curcumin derivative in water environment has evaluated by Radial Distributions Functions (RDF) calculated via Molecular Dynamics (MD) simulations. The inhibitory activity of the title compound was evaluated by in silico methods and the stability of the protein-ligand complexes were studied using Molecular Dynamics simulations and MM-PBSA analysis. With this detailed study, we hope to motivate scientific community to develop new curcumin derivatives against SARS-CoV-2 virus.

3.
Molecules ; 28(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36677711

RESUMO

Due to the inability of conventional wastewater treatment procedures to remove organic pharmaceutical pollutants, active pharmaceutical components remain in wastewater and even reach tap water. In terms of pharmaceutical pollutants, the scientific community focuses on ß-blockers due to their extensive (over)usage and moderately high solubility. In this study, the photocatalytic activity of V2O5 was investigated through the degradation of nadolol (NAD), pindolol (PIN), metoprolol (MET), and their mixture under ultraviolet (UV) irradiation in water. For the preparation of V2O5, facile hydrothermal synthesis was used. The structural, morphological, and surface properties and purity of synthesized V2O5 powder were investigated by scanning electron microscopy (SEM), X-ray, and Raman spectroscopy. SEM micrographs showed hexagonal-shaped platelets with well-defined morphology of materials with diameters in the range of 10−65 µm and thickness of around a few microns. X-ray diffraction identified only one crystalline phase in the sample. The Raman scattering measurements taken on the catalyst confirmed the result of XRPD. Degradation kinetics were monitored by ultra-fast liquid chromatography with diode array detection. The results showed that in individual solutions, photocatalytic degradation of MET and NAD was relatively insignificant (<10%). However, in the PIN case, the degradation was significant (64%). In the mixture, the photodegradation efficiency of MET and NAD slightly increased (15% and 13%). Conversely, it reduced the PIN to the still satisfactory value of 40%. Computational analysis based on molecular and periodic density functional theory calculations was used to complement our experimental findings. Calculations of the average local ionization energy indicate that the PIN is the most reactive of all three considered molecules in terms of removing an electron from it.

4.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36678622

RESUMO

The emerging interest in the field of coordination chemistry and their biological applications has created a novel impact in the field of chemical biology. With this motivation, in this work we have synthesized a novel benzimidazole derived imine ligand, 2-((E)-((1H-benzo[d]-2-yl)methylimino)methyl)-4-fluorophenol (HBMF) and its Co(III) and Cu(II) complexes. The metal complexes (C1-C4) were synthesized in 2:1 (HBMF: metal ion) and 1:1:1 (HBMF: metal ion: 1,10-phen) ratios. Structural elucidations of all the synthesized compounds were performed using FT-IR, UV-Visible, NMR, Mass spectroscopy and elemental analysis techniques. A combination of first principles calculations and molecular dynamics simulations was applied to computationally investigate the structural, reactive, and spectroscopic properties of the newly synthesized HBMF ligand and its complexes with copper and cobalt metal ions. Quantum-mechanical calculations in this study were based on the density functional theory (DFT), while molecular dynamics (MD) simulations were based on the OPLS4 force field. The DFT calculations were used to obtain the reactive and spectroscopic properties of the ligand and its complexes, while molecular dynamics (MD) simulations were used to address the ligand's reactivity with water. Further, the in vitro anti-proliferative activity of the compounds was tested against the A549, Ehrlich-Lettre ascites carcinoma (EAC), SIHA and NIH3T3 cell lines. The biological results depicted that the compound C4, with molecular formula C27H23Cl2CoFN5O3 exhibited profound anti-proliferative activity against the EAC cell line with a significant IC50 value of 10 µm when compared to its parent ligand and other remaining metal complexes under study. Various assays of hematological parameters (alkaline phosphate, creatinine, urea, RBC and WBC) were performed, and significant results were obtained from the experiments. Furthermore, the effect of C4 on neovascularization was evaluated by stimulating the angiogenesis with rVEGF165, which was compared with non-tumor models. The EAC cells were cultured in vivo and administrated with 50 and 75 mg/kg of two doses and tumor parameters were evaluated.

5.
Nanomaterials (Basel) ; 12(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36500815

RESUMO

Water pollution is a significant issue nowadays. Among the many different technologies for water purification, photocatalysis is a very promising and environment-friendly approach. In this study, the photocatalytic activity of Sr0.9La0.1TiO3 (SLTO) and Sr0.25Ca0.25Na0.25Pr0.25TiO3 (SCNPTO) nano-sized powders were evaluated by degradation of pindolol in water. Pindolol is almost entirely insoluble in water due to its lipophilic properties. The synthesis of the SCNPTO was performed using the reverse co-precipitation method using nitrate precursors, whereas the SLTO was produced by spray pyrolysis (CerPoTech, Trondheim Norway). The phase purity of the synthesized powders was validated by XRD, while HR-SEM revealed particle sizes between 50 and 70 nm. The obtained SLTO and SCNPTO powders were agglomerated but had relatively similar specific surface areas of about 27.6 m2 g-1 and 34.0 m2 g-1, respectively. The energy band gaps of the SCNPTO and SLTO were calculated (DFT) to be about 2.69 eV and 3.05 eV, respectively. The photocatalytic performances of the materials were examined by removing the pindolol from the polluted water under simulated solar irradiation (SSI), UV-LED irradiation, and UV irradiation. Ultra-fast liquid chromatography was used to monitor the kinetics of the pindolol degradation with diode array detection (UFLC-DAD). The SLTO removed 68%, 94%, and 100% of the pindolol after 240 min under SSI, UV-LED, and UV irradiation, respectively. A similar but slightly lower photocatalytic activity was obtained with the SCNPTO under identical conditions, resulting in 65%, 84%, and 93% degradation of the pindolol, respectively. Chemical oxygen demand measurements showed high mineralization of the investigated mixtures under UV-LED and UV irradiation.

6.
Molecules ; 27(19)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36235119

RESUMO

This study investigated the potential of zeolites (NH4BETA, NH4ZSM-5, and NaY) to remove two frequently used dyes, methylene blue (MB) and rhodamine B (RB), from an aqueous environment. The removal of dyes with zeolites was performed via two mechanisms: adsorption and photocatalysis. Removal of dyes through adsorption was achieved by studying the Freundlich adsorption isotherms, while photocatalytic removal of dyes was performed under UV irradiation. In both cases, the removal experiments were conducted for 180 min at two temperatures (283 K and 293 K), and dye concentrations were determined spectrophotometrically. Additionally, after photodegradation, mineralization was analyzed as chemical oxygen demand. A computational analysis of the structures of MB and RB was performed to gain a deeper understanding of the obtained results. The computational analysis encompassed density functional theory (DFT) calculations and analysis of two quantum-molecular descriptors addressing the local reactivity of molecules. Experimental results have indicated that the considered zeolites effectively remove both dyes through both mechanisms, especially NH4BETA and NH4ZSM-5, due to the presence of active acidic centers on the outer and inner surfaces of the zeolite. The lowest efficiency of dye removal was achieved in the presence of NaY zeolite, which has a lower SiO2/Al2O3 ratio. A more efficient reduction was completed for RB dye, which agrees with the computationally obtained information about reactivity.


Assuntos
Poluentes Químicos da Água , Zeolitas , Adsorção , Corantes/análise , Azul de Metileno/química , Dióxido de Silício , Água/química , Poluentes Químicos da Água/análise , Zeolitas/química
7.
Nanomaterials (Basel) ; 12(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35683756

RESUMO

Single-walled carbon nanotubes (SWCNTs) are well-known for their excellent electrical conductivity. One promising application for SWCNT-based thin films is as transparent electrodes for uncooled mid-IR detectors (MIR). In this paper, a combination of computational and experimental studies were performed to understand the chemistry behind the stability of carboxylic SWCNTs (SWCNTs-COOH) dispersions in different solvents. A computational study based on the density functional tight-binding (DFTB) method was applied to understand the interactions of COOH-functionalized carbon nanotubes with selected solvents. Attention was focused on understanding how the protonation of COOH groups influences the binding energies between SWCNTs and different solvents. Thin film electrodes were prepared by alternately depositing PEI and SWCNT-COOH on soda lime glass substrates. To prepare a stable SWCNT dispersion, different solvents were tested, such as deionized (DI) water, ethanol and acetone. The SWCNT-COOH dispersion stability was tested in different solvents. Samples were prepared to study the relationship between the number of depositions, transparency in the MIR range (2.5-5 µm) and conductivity, looking for the optimal thickness that would satisfy the application. The MIR transparency of the electrode was reduced by 20% for the thickest SWCNT layers, whereas sheet resistance values were reduced to 150-200 kΩ/sq.

8.
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
9.
J Biomol Struct Dyn ; 40(21): 10952-10961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34278966

RESUMO

Anthracenes are aromatic compounds with flexible structure and reactivity which are of great interest to theoretical and experimental chemists. Theoretical investigations of 1,4-dihydroxy-5,8-bis[2-(2-hydroxyethylamino)ethylamino]anthracene-9,10-dione (Mitoxantrone) (DDEA) based on density functional theory, molecular dynamics and adsorption on fullerene are reported in the present research. The suitable situation for adsorption with fullerene (C60) is the cyclohex-2-ene-1,4-dione ring of DDEA. Selected quantum-molecular descriptors have been calculated to predict the most reactive sites of the DDEA molecule. Interactions of DDEA with water have been studied using MD simulations. MD simulations were also used to study solubility parameter, a significant quantity for the development of pharmaceutical formulations. The affinity of DDEA on human dihydrofolate reductase and deoxyuridine triphosphatase enzymes was investigated by MD simulation of the protein-ligand complex obtained by molecular docking study.Communicated by Ramaswamy H. Sarma.


Assuntos
Fulerenos , Simulação de Dinâmica Molecular , Humanos , Fulerenos/química , Tetra-Hidrofolato Desidrogenase , Simulação de Acoplamento Molecular , Adsorção , Antracenos
10.
J Mol Model ; 27(8): 217, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34218339

RESUMO

Spectroscopic analysis of 1-(2-fluorophenyl)-3-[3-(trifluoromethyl)phenyl]thiourea (FPTT) is reported. Experimental and theoretical analyses of FPTT, with molecular dynamics (MD) simulations, are reported for finding different parameters like identification of suitable excipients, interactions with water, and sensitivity towards autoxidation. Molecular dynamics and docking show that FPTT can act as a potential inhibitor for new drug. Additionally, local reactivity, interactivity with water, and compatibility of FPTT molecule with frequently used excipients have been studied by combined application of density functional theory (DFT) and MD simulations. Analysis of local reactivity has been performed based on selected fundamental quantum-molecular descriptors, while interactivity with water was studied by calculations of radial distribution functions (RDFs). Compatibility with excipients has been assessed through calculations of solubility parameters, applying MD simulations. Graphical abstract Reactive sites identified.


Assuntos
Neoplasias/tratamento farmacológico , Termodinâmica , Tioureia/química , Teoria da Densidade Funcional , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Neoplasias/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Tioureia/análogos & derivados , Água/química
11.
Sci Total Environ ; 768: 144991, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736306

RESUMO

In this work, we have experimentally and computationally investigated the process of hydrolysis and photolysis of cephalosporin antibiotics with ceftriaxone (CEF) as a model compound. The CEF hydrolysis was investigated in ultrapure and natural water, at 25 ± 1 °C and 4 ± 1 °C in the dark. It was found that CEF after 100 and 900 days at 25 ± 1°C and 4 ± 1 °C, respectively practically completely removed from ultrapure water. The CEF hydrolysis in natural water was five and three times slower at 25 ± 1 °C and 4 ± 1 °C, respectively than in ultrapure water. Further, the efficiency of direct photolysis (solar/UVA-B) and solar/H2O2 treatment of CEF was investigated. Under UVA-B radiation 95.6% of CEF was removed after 60 min, while for the same time of solar radiation degradation was practically not observed (only 3.2%). Also, the effects of different concentrations of H2O2 (0-150 mM) in the presence/absence of solar radiation were studied. The most efficient solar/H2O2 treatment was in the presence of 90 mM H2O2, whereby 66.8% of CEF was removed after 60 min (41.8% by indirect photolysis, 21.8% by H2O2-oxidation, and 3.2% by direct photolysis). Radial distribution functions (RDF) provided information about the distribution of water around the CEF molecule. Aside from the RDF, investigation of intramolecular noncovalent interactions and calculations of bond dissociation energies for hydrogen abstraction enabled understanding of degradation mechanism of CEF. In order to investigate sensitivity of CEF towards the radical attacks, the concept of Fukui functions was used. The structures of intermediates and degradation pathways were suggested by UHPLC-LTQ OrbiTrap MS and density functional theory calculations. Toxicity assessments showed that intermediates formed during hydrolysis exerted only mild cell growth effects in selected cell lines.


Assuntos
Ceftriaxona , Poluentes Químicos da Água , Antibacterianos/toxicidade , Peróxido de Hidrogênio , Hidrólise , Cinética , Fotólise , Raios Ultravioleta , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
Molecules ; 25(12)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580359

RESUMO

Herein we report the synthesis and structural elucidation of two novel imine-based ligands, 2-(1,10-phenanthrolin-5-yl)imino)methyl)-5-bromophenol (PIB) and N-(1,10-phenanthrolin-5-yl)-1-(thiophen-3-yl)methanimine (PTM) ligands. An in vitro cytotoxicity assay of the synthesized molecules was carried out against breast, cervical, colorectal, and prostate cancer cell lines as well as immortalized human keratinocytes. The observations indicated that both the molecules possesses dose-dependent selective cytotoxicity of cancer cells with no detrimental effect on the normal cell lines. Furthermore, the detailed computational analysis of newly synthetized ligands (PIB and PTM) has been conducted in order to identify their most important parts from the perspective of local reactivity. The IC50 values of PIB treatment on MCF-7, HeLa, HCT-116 and PC-3 were 15.10, 16.25, 17.88, 17.55 and 23.86 micromoles, respectively. Meanwhile, the IC50 values of PTM on MCF-7, HeLa, HCT-116, PC-3 and HaCat were observed to be 14.82, 15.03, 17.88, 17.28 and 21.22 micromoles, respectively. For computational analysis, we have employed the combination of Density Functional Theory (DFT) calculations and MD simulations. DFT calculations provided us with information about structure and reactivity descriptors based on the electron distribution. Surfaces of molecular electrostatic potential (MEP) and averaged local ionization energy (ALIE) indicated the sites within studied molecules that are most reactive. These results indicated the importance of nitrogen atoms and OH group. Additionally, the values of bond dissociation for hydrogen abstraction showed that both molecules, especially the PTM, are stable toward the influence of autoxidation mechanism. On the other side, MD simulations gave us an insight how ligands interact with water molecules. Namely, the radial distribution functions (RDF) indicated that the hydrogen atom of the OH group in the case of the PIB has the most pronounced interactions with water.


Assuntos
Proliferação de Células/efeitos dos fármacos , Iminas/farmacologia , Neoplasias/tratamento farmacológico , Fenantrolinas/farmacologia , Linhagem Celular Tumoral , Humanos , Iminas/síntese química , Iminas/química , Ligantes , Simulação de Acoplamento Molecular , Neoplasias/patologia , Fenantrolinas/síntese química , Fenantrolinas/química , Água/química
13.
J Hazard Mater ; 393: 122490, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32197201

RESUMO

In this work, we have investigated the stability of pindolol (PIN), a non-selective ß1-blocker detected in the river and wastewater of hospitals, in water solution under solar irradiation. Further, detailed insights into the stability of PIN were obtained by the density functional theory (DFT) calculations and molecular dynamics simulations. The kinetics of PIN photocatalytic degradation and mineralization has been studied using four commercial photocatalysts ZnO and TiO2 (P25, Hombikat, and Wackherr). It was found that the major role in degradation of PIN play the reactive hydroxyl radicals. The structures of degradation intermediates were suggested by LC-ESI-MS/MS and DFT calculations. Also, DFT calculations were used to refine molecular structures of intermediates and obtain their geometries. Toxicity of PIN and its mixtures formed during photocatalytic degradation were investigated using mammalian cell lines (H-4-II-E, HT-29, and MRC-5). The H-4-II-E cell line was the most sensitive to PIN and its photodegradation mixtures. The computational results were combined with the experimental data on the amounts of degradation intermediates for determination of the intermediates that were principally responsible for the toxicity. Intermediate with two hydroxyl groups, positioned on indole ring in meta and para positions, was proposed as the one with the highest contribution to toxicity.


Assuntos
Pindolol/química , Luz Solar , Titânio/efeitos da radiação , Poluentes Químicos da Água/química , Óxido de Zinco/efeitos da radiação , Animais , Catálise , Linhagem Celular , Humanos , Cinética , Modelos Moleculares , Fotólise , Pindolol/toxicidade , Ratos , Titânio/química , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/química
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117414, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31376725

RESUMO

This article represents the spectroscopic and computational studies of two new pyrazine compounds. In order to establish the structure and functional nature of the compounds, we have employed Fourier transformed infrared (FT-IR) and Raman spectra, nuclear magnetic resonance (NMR) spectra, and ultraviolet (UV) absorptions and have compared them with the simulated computational spectra and found that they are in the agreeable range. Simulated hyperpolarisability values are used to obtain the nonlinear optic (NLO) activity of the compound, to be used in organic electronic materials. The charge transfer and related properties was investigated by the simulation of electronic spectrum with time dependent density functional theory (TD-DFT). Natural transition orbitals (NTO) provides information about which region of the molecules are more involved in the electronic transitions and the charge transfer properties for the lowest energy excitation have been analyzed on the basis of electron density variation. Molecular dynamics simulations provide information about the behavior of the molecule in solutions. Frontier orbital analysis and study of various reactivity descriptors like ALIE and Fukui provided deep knowledge on the reactivity side. Molecular docking has been also performed to investigate the interaction between title molecules and exhibits inhibitory activity against Pseudomonas aeruginosa Enoyl-Acyl carrier protein reductase (Fabl).


Assuntos
Pirazinas , Antibacterianos/análise , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Descoberta de Drogas , Simulação de Acoplamento Molecular , Pirazinas/análise , Pirazinas/química , Pirazinas/metabolismo , Análise Espectral , Eletricidade Estática
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117580, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31748158

RESUMO

A set of experimental and computational techniques have been applied for the understanding of fundamental spectroscopic and reactive properties of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (diuron) compound. Experimental techniques employed in this study encompassed spectroscopic characterization via IR and Raman approaches, while optical properties were studied by measurements of UV/Vis spectra. The thermogravimetric analysis was also studied in order to analyze the stability of diuron. Aside from the determination of reactive properties, DFT calculations on isolated molecules were also used to thoroughly visualize and analyze spectroscopic properties such as IR and UV/Vis. MD simulations were used in order to understand interactions with water, while periodic DFT calculations were used in order to analyze band structure and density of states of the diuron crystal structure. Since the crystal structure of diuron is known, it was used in order to extract the relevant molecular pairs and investigate interactions between them by DFT and symmetry adapted perturbation theory approaches (SAPT).

16.
Phys Chem Chem Phys ; 21(42): 23329-23337, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31616869

RESUMO

Interactions between fullerene C24 and a frequently used supplement for sport activities, ephedrine (EPH), have been studied in detail by a combination of density functional theory (DFT), time dependent DFT (TD-DFT) calculations, the symmetry-adapted perturbation theory (SAPT) approach and molecular dynamics (MD) simulations. Information about interaction energies and non-covalent interactions formed between C24 and EPH have been obtained by DFT calculations. TD-DFT calculations have been used in order to obtain UV/vis spectra and to check whether the presence of the EPH molecule produces significant changes in the spectrum. The SAPT approach has been employed in order to decompose the interaction energy into components and therefore to better understand the physical origins of interaction between C24 and EPH. Last, but not least, MD simulations have been used in order to track the influence of temperature on the interactions between C24 and EPH.


Assuntos
Efedrina/química , Fulerenos/química , Sítios de Ligação , Teoria da Densidade Funcional , Simulação de Dinâmica Molecular , Temperatura , Termodinâmica
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 222: 117188, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31176999

RESUMO

2-[N-(carboxymethyl)anilino] acetic acid (PIDAA) molecule has been spectroscopically characterized and computationally investigated for its fundamental reactive properties by a combination of density functional theory (DFT) calculations, molecular dynamics (MD) simulations and molecular docking procedure. A comparison drawn between the simulated and experimentally attained spectra by FT-Raman and FT-IR showed concurrence. The natural bond orbital (NBO) analysis enabled in comprehending the stability and charge delocalization in the title molecule. The first hyperpolarizability which is an important parameter for future studies of nonlinear optics (NLO) was calculated to check the potential of the molecule to be an NLO material. Besides, frontier molecular orbitals (FMO), electron localization function (ELF) and localized orbital locator (LOL) analysis were performed. Energy gap (ΔE), electronegativity (χ), chemical potential (µ), global hardness (η), softness (S), Mulliken population analysis on atomic charges and thermodynamic properties of the title compound at different temperatures have been calculated. The local reactive properties of PIDAA have been addressed by MEP and ALIE surfaces, together with bond dissociation energy for hydrogen abstraction (H-BDE). MD simulations have been used in order to identify atoms with pronounced interactions with water molecules. The pharmaceutical potential of PIDAA has been considered by the analysis of drug likeness parameters and molecular docking procedure. The biological activity of the molecule in terms of molecular docking has been analyzed theoretically for the treatment of SARS and minimum binding energy calculated. The Ramachandran plot was used to check the stereochemistry of the protein structure. In addition, a comparison of the physiochemical parameters of PIDAA and commercially available drugs (Yu et al., 2004; Tan et al., 2004; Elshabrawy et al., 2014; Chu et al., 2004; Gopal Samy and Xavier, 2015) were carried out.


Assuntos
Compostos de Anilina/química , Teoria da Densidade Funcional , Elétrons , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica , Água/química
18.
Comput Biol Chem ; 77: 131-145, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30312906

RESUMO

Spectroscopic profiling in terms of FT-IR, FT-Raman, UV-vis and NMR in addition to reactivity study by density functional theory (DFT) and molecular dynamics (MD) simulations of 3-(4-chlorophenyl)-N,N-dimethyl-3-pyridin-2-ylpropan-1-amine (C16H19ClN2) have been discussed. In order to assign principal vibrational numbers, the Potential energy distribution (PED) analysis has been executed. Frontier molecular orbitals (FMOs) analysis in addition to the stabilization energy and natural hybrid orbital analysis has been done. Local reactivity properties of this compound have been addressed through molecular electrostatic potential (MEP) and average local ionization energy (ALIE) surfaces. The bond dissociation energy for hydrogen abstraction (H-BDE) and chemical bonding analysis in terms of electron localization function gave details regarding the Pauli exchange repulsion effect in the electrons of the molecule. Molecular dynamics simulation has been performed in order to understand reactivity of title molecule with water. Molecular docking study was executed to evaluate the potential of the title molecule to bind with 5-HT1 A serotonin receptor and thus can be a lead compound for developing new SSRI (Selective serotonin reuptake inhibitor) drug. Aside from molecular docking, drug likeness parameters have been also considered and by QSAR modeling the comparison of physiochemical parameters of commercially available SSRI drugs and title molecule is carried out.


Assuntos
Antidepressivos/química , Teoria da Densidade Funcional , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores Seletivos de Recaptação de Serotonina/química , Espectroscopia de Ressonância Magnética , Oxirredução , Relação Quantitativa Estrutura-Atividade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Termodinâmica
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 205: 95-110, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30015034

RESUMO

This paper reports the synthesis of 5-(5-methyl-benzofuran-3-ylmethyl)-3H- [1, 3, 4] oxadiazole-2-thione (5MBOT) and characterization by FT-IR, FT-Raman, 1H NMR, 13C NMR and UV spectral studies. The density functional theory (DFT) calculations have been executed for the 5MBOT using B3LYP/6-31++G (d, p) basis set. The fundamental modes of the vibrations were designated by the potential energy distribution (PED), and the computed and experimental values support each other. The 1H NMR and 13C NMR chemical shifts of 5MBOT were estimated by gauge-including atomic orbitals (GIAO) method and compared with the experimental chemical shifts. The UV-Vis method used to study the visible absorption maxima (λmax) by using Time-Dependent DFT. Further, the Mulliken population analysis (MPA), natural population analysis (NPA) charges, thermodynamic properties at different temperatures were presented. The calculated HOMO and LUMO energies show that charge transfer within the molecule. The natural bonds orbital (NBO) also computed. Optoelectronic properties have been carried out by combination of DFT calculations and molecular dynamics (MD) simulations, in order to assess the potential of this structure for applications in organic electronics. Further, the study encompassed calculations of reorganization energies for holes and electrons and charge transfer rates. DFT calculations have been also used in order to identify locations possibly sensitive towards the autoxidation mechanism, which correlates between bond dissociation energy for hydrogen abstraction and the mechanism. The MD simulations have been used to understand interaction of 5MBOT with water molecules. Molecular docking studies reveals the antifungal activity of 5MBOT may be due to hydrogen bonding and hydrophobic interactions with different antifungal proteins.


Assuntos
Benzofuranos/química , Oxidiazóis/química , Tionas/química , Benzofuranos/síntese química , Simulação de Acoplamento Molecular , Oxidiazóis/síntese química , Análise Espectral , Tionas/síntese química
20.
RSC Adv ; 8(32): 18023-18029, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35542090

RESUMO

We report the synthesis of a new imine based ligand, 3-((3-methoxybenzylidene)amino)-1H-pyrazol-5-ol (HL) and its Cu(ii) complexes in 2 : 1 (HL : metal) and 1 : 1 : 1 (HL : metal : HQ) stoichiometric ratio using 8-hydroxyquinoline (HQ) as an additional bidentate ligand. The synthesized ligand (HL) and its Cu(ii) complexes (1 and 2) are structurally characterized using FT-IR, electronic absorption and emission, NMR and MS techniques. Furthermore, the complexation of Cu2+ with HL leads to the immediate formation of brown colour solution which indicates that HL can act as simple colorimetric sensor for Cu2+ ions. We further investigated that the sensor could selectively bind to the Cu2+ ions even in the presence of competitive ions such as Mn2+, Fe2+, Co2+, Ni2+, Zn2+, Ag+ and Na+ ions in aqueous solutions which was studied by electronic absorption spectroscopy. The HL ligand has been investigated for its reactive properties by density functional theory (DFT) calculations. Quantum molecular descriptors describing local reactive properties have been calculated in order to identify the most reactive molecule sites of title compounds. DFT calculations encompassed molecular electrostatic potential (MEP), local average ionization energies (ALIE), Fukui functions and bond dissociation energies for hydrogen abstraction (H-BDE).

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