Molecular Investigations of the Newly Synthesized Azomethines as Antioxidants: Theoretical and Experimental Studies

2019 ◽  
Vol 19 (6) ◽  
pp. 419-433 ◽  
Author(s):  
Siyamak Shahab ◽  
Masoome Sheikhi ◽  
Liudmila Filippovich ◽  
Evgenij Dikusar ◽  
Anhelina Pazniak ◽  
...  
Keyword(s):  
Density Functional ◽  
Energy Gap ◽  
Experimental Studies ◽  
Antioxidant Property ◽  
Nbo Analysis ◽  
Antioxidant Potential ◽  
Functional Theory ◽  
Homo And Lumo ◽  
Intramolecular Hydrogen ◽  
Activity Mechanism

: In this study, the antioxidant property of new synthesized azomethins has been investigated as theoretical and experimental. Methods and Results: Density functional theory (DFT) was employed to investigate the Bond Dissociation Enthalpy (BDE), Mulliken Charges, NBO analysis, Ionization Potential (IP), Electron Affinities (EA), HOMO and LUMO energies, Hardness (η), Softness (S), Electronegativity (µ), Electrophilic Index (ω), Electron Donating Power (ω-), Electron Accepting Power (ω+) and Energy Gap (Eg) in order to deduce scavenging action of the two new synthesized azomethines (FD-1 and FD-2). Spin density calculations and NBO analysis were also carried out to understand the antioxidant activity mechanism. Comparison of BDE of FD-1 and FD-2 indicate the weal antioxidant potential of these structures. Conclusion: FD-1 and FD-2 have very high antioxidant potential due to the planarity and formation of intramolecular hydrogen bonds.

Antitumor and Antioxidant Activities of the New Synthesized Azomethine Derivatives: Experimental and Theoretical Investigations

2020 ◽  
Vol 17 ◽  
Author(s):  
Siyamak Shahab ◽  
Masoome Sheikhi ◽  
Liudmila Filippovich ◽  
Evgenij Dikusar ◽  
Radwan A. Alnajjar ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Density Functional ◽  
Energy Gap ◽  
Antioxidant Activities ◽  
Antioxidant Property ◽  
Nbo Analysis ◽  
Molecular Structures ◽  
Experimental Investigations ◽  
Intramolecular Hydrogen ◽  
Activity Mechanism

Aims: In this study, the antioxidant property of eight new azomethin derivatives has been investigated as theoretical and experimental. Background: Azomethines have antioxidant activity. Objective: We have been studied the molecular structures and antioxidant property these derivatives have been studied for the first time. Method: The molecular structures were optimized using Density functional theory (DFT). Result: The Bond Dissociation Enthalpy (BDE), Mulliken Charges, NBO analysis, Ionization Potential (IP), Electron Affinities (EA), HOMO and LUMO energies, Hardness (η), Softness (S), Electronegativity (μ), Electrophilic Index (ω), Electron Donating Power (ω-), Electron Accepting Power (ω+) and Energy Gap (Eg) in order to deduce scavenging action of the eight new synthesized azomethines (DIA-3,4,5,6,7,8,9,10) have been calculated. Spin density calculations and NBO analysis were also carried out to understand the antioxidant activity mechanism. Conclusion: These molecules have high antioxidant potential due to the planarity and formation of intramolecular hydrogen bonds. Other: Experimental investigations establish high antioxidant and antitumor activities of the synthesized azomethine derivatives.

scholarly journals Molecular structure, NBO analysis, first hyper polarizability, and homo-lumo studies of π-extended tetrathiafulvalene (EXTTF) derivatives connected to π-nitro phenyl by density functional method

2018 ◽  
Vol 6 (1) ◽  
pp. 114
Author(s):  
Tahar Abbaz ◽  
Amel Bendjeddou ◽  
Didier Villemin
Keyword(s):  
Density Functional ◽  
Density Functional Method ◽  
Nbo Analysis ◽  
Functional Method ◽  
Total Charge ◽  
Linear Optics ◽  
Functional Theory ◽  
Non Linear Optics ◽  
Homo And Lumo ◽  
Homo Lumo

In these study we have been obtained the structural properties of (exTTF) derivatives 1-4 by using B3LYP/6-31G(d,p) of Density Functional Theory (DFT) utilizing Becke three exchange functional and Lee Yang Paar correlation functional. The calculation of first hyperpolarizability shows that the molecules are attractive molecules for future applications in non-linear optics. Molecular electrostatic potential (MEP) at a point in the space around a molecule gives an indication of the net electrostatic effect produced at that point by the total charge distribution of the molecule. The calculated HOMO and LUMO energies show that charge transfer occurs within these molecules. 

scholarly journals Spectroscopic and Electrochemical Investigations of New 5-oxo-2- Phenyloxazol-4(5H)-ylidene Based Triazine Derivatives

2019 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Density Functional ◽  
Energy Gap ◽  
Electronic Absorption Spectra ◽  
Spectroscopic Properties ◽  
Functional Theory ◽  
Structural Framework ◽  
Triazine Derivatives ◽  
Homo And Lumo ◽  
Cyclic Voltammetry Analysis ◽  
Oxazolone Ring

The present study reports the two step synthesis of a novel oxazolone derivative, 4-((4,6-bis(4-((Z)-(5-oxo-2-phenyloxazol-4(5H)-ylidene) methyl)phenoxy)-1,3,5-triazin-2-yl) oxy) benzaldehyde (CBOZ (5)), containing two oxazolone ring substituted with central triazine nucleus in their structural framework. The structural and spectroscopic properties of synthesized CBOZ (5) were characterized by FTIR, 1HNMR, 13CNMR, and mass spectroscopic analysis. The UV-Vis absorption of CBOZ (5) showed a single absorption band at ~370 nm due to π-π* transition with the estimated energy gap of ~3.02 eV. Cyclic voltammetry analysis revealed that the synthesized CBOZ (5) obtained the HOMO and LUMO values of -5.87 eV and-2.85 eV, respectively. Density functional theory (DFT) studies were carried out to predict the electronic absorption spectra of CBOZ (5) and the obtained values were in excellent agreement with the experimental results.

A DFT-D study on the stability and intramolecular interactions of the salts of 1,2,3- and 1,2,4-triazoles

2014 ◽  
Vol 92 (11) ◽  
pp. 1111-1117
Author(s):  
Xueli Zhang ◽  
Xuedong Gong
Keyword(s):  
Hydrogen Bonds ◽  
Density Functional ◽  
Energy Gap ◽  
Lattice Energy ◽  
Intramolecular Interactions ◽  
Dispersion Energy ◽  
Functional Theory ◽  
Formation Reaction ◽  
The Stability ◽  
Intramolecular Hydrogen

Nitrogen-rich 1,2,4-triazole (1) and 1,2,3-triazole (2) react as bases with the oxygen-rich acids HNO3 (a), HN(NO2)2 (b), and HClO4 (c) to produce energetic salts (1a, 1b, and 1c and 2a, 2b, and 2c, respectively) potentially applicable to composite explosives and propellants. In this study, these salts were studied with the dispersion-corrected density functional theory. For the isomers such as 1a and 2a, the more negative ΔrGm of the formation reaction leads to a higher thermally stable salt. The ability to form intramolecular hydrogen bonds predicted with the quantum theory of atoms in molecules has the order of 2 > 1. Different hydrogen bonds result in different second-order perturbation energies, redshifts in IR, and electron density differences. The charge transfer, binding energy, dispersion energy, lattice energy, and energy gap between frontier orbits in the salts of 1 are larger than those of 2, which is helpful for stabilizing the former, and 1 is more obviously stabilized than 2 by formation of salts. Different conformations of 1 and 2 hardly affect the frontier orbital distributions. Base 1 is a more preferred base than 2 to form salts.

DFT Study on Geometric and Electronic Structures Properties of Dye Sensitizers

2015 ◽  
Vol 748 ◽  
pp. 197-200
Author(s):  
Mei Juan Cao ◽  
Zhi Cheng Sun ◽  
Lu Hai Li ◽  
Yuan Bin She ◽  
Zuo Lin Yang ◽  
...  
Keyword(s):  
Electronic Transport ◽  
Electronic Structures ◽  
Energy Barrier ◽  
Density Functional ◽  
Energy Gap ◽  
Frontier Molecular Orbital ◽  
Central Metal ◽  
Functional Theory ◽  
Homo And Lumo ◽  
Porphyrin Core

A series of porphyrin sensitizers with different central metal ions (PMn, PFe, PCo, PNi, PCu, and PZn) have been studied based on density functional theory (DFT). The geometric structure of the dyes was optimized and the frontier molecular orbital were calculated. The result shows that the LUMO levels of PFe, PNi and PZn were much lower than that of PMn, PCo and PCu, which suggest a lower energy barrier for electron transfer from the donor to the acceptor tunneling. Furthermore, the energy gap of HOMO and LUMO for PFe was only 0.81 eV, it indicates a significant red shift of the absorption spectrum. The LUMO of PMn, PNi, PCu and PZn were mainly decocalized on the porphyrin core and the bridge moiety, which was beneficial to electronic transport.

scholarly journals Spectroscopic, Electronic and Optical Properties of 4-Nitroimidazole using DFT Calculations

2020 ◽  
Vol 33 (1) ◽  
pp. 83-88
Author(s):  
S. Jeyavijayan ◽  
Palani Murugan
Keyword(s):  
Density Functional ◽  
Energy Gap ◽  
Dft Method ◽  
Nbo Analysis ◽  
Spectroscopic Techniques ◽  
Functional Theory ◽  
Raman Spectroscopic ◽  
Homo Lumo ◽  
Total Energy Distribution ◽  
Ft Raman

Theoretical and experimental vibrational spectra of 4-nitroimidazole were studied by FTIR, FT-Raman spectroscopic techniques and density functional theory (DFT) method. The contributions of the different modes to each wavenumber were confirmed using total energy distribution (TED). The optimized parameters and thermodynamic properties of 4-nitroimidazole have been computed. The charge transfer interactions of the molecule were explained from the small value of HOMO-LUMO energy gap. The NBO analysis, Mulliken’s plot and MEP studies of the molecule have also been reported.

scholarly journals (E)-1-(Benzo[d][1,3]dioxol-5-yl)-3-([2,2′-bithiophen]-5-yl)prop-2-en-1-one: crystal structure, UV–Vis analysis and theoretical studies of a new π-conjugated chalcone

2019 ◽  
Vol 75 (5) ◽  
pp. 632-637
Author(s):  
Ainizatul Husna Anizaim ◽  
Muhamad Fikri Zaini ◽  
Muhammad Adlan Laruna ◽  
Ibrahim Abdul Razak ◽  
Suhana Arshad
Keyword(s):  
Density Functional ◽  
Energy Gap ◽  
Weak Interactions ◽  
Basis Set ◽  
Molecular Orbital Calculations ◽  
Functional Theory ◽  
Compound C ◽  
Homo And Lumo ◽  
Experimental Values ◽  
Homo Lumo

In the title compound, C18H12O3S2, synthesized by the Claisen–Schmidt condensation method, the essentially planar chalcone unit adopts an s-cis configuration with respect to the carbonyl group within the ethylenic bridge. In the crystal, weak C—H...π interactions connect the molecules into zigzag chains along the b-axis direction. The molecular structure was optimized geometrically using Density Functional Theory (DFT) calculations at the B3LYP/6–311 G++(d,p) basis set level and compared with the experimental values. Molecular orbital calculations providing electron-density plots of HOMO and LUMO molecular orbitals and molecular electrostatic potentials (MEP) were also computed both with the DFT/B3LYP/6–311 G++(d,p) basis set. The experimental energy gap is 3.18 eV, whereas the theoretical HOMO–LUMO energy gap value is 2.73 eV. Hirshfeld surface analysis was used to further investigate the weak interactions present.

scholarly journals Skin Sensitization Calculation, Topical anti-inflammatory effect and DFT Study of New Indole-Hydrazone

2019 ◽  
Vol 9 (6) ◽  
pp. 43-46
Author(s):  
Kamel Mokhnache ◽  
Ahlem Karbab ◽  
EL-Khamsa Soltani ◽  
Soraya Madoui ◽  
Hanane Khither ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Experimental Studies ◽  
Skin Sensitization ◽  
Mice Model ◽  
Functional Theory ◽  
Anti Inflammatory ◽  
Inflammatory Effect

A new indol-hydrazone (IH); N'-[(E)-(5-bromo-1H- indol-3-yl) methylidene] pyridine-4-carbohydrazide was selected for theoretical and experimental studies. Molecular structure proprieties were investigated using density functional theory (DFT) via B3LYP/6-31G (d,p), skin sensitization prediction was carried out using Pred Skin software program. The obtained results demonstrate the reactivity of IH with Energy gap (Δ) of 0.0579 a.u, low sensitizer effect towards human skin with probability of 60 %, and an excellent topical anti-inflammatory effect against xylen-induced ear odema in mice model with inhibition percentages of 81.48%. Keyword: Hydrazone, skin sensitization, Topical, Anti-inflammatory.

Dissymmetric Bay-Functionalized Perylenediimides

Synlett ◽  
2018 ◽  
Vol 29 (13) ◽  
pp. 1693-1699 ◽  
Author(s):  
Prabhpreet Singh ◽  
Kapil Kumar ◽  
Gaurav Bhargava ◽  
Subodh Kumar
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Energy Gap ◽  
Twist Angle ◽  
Density Functional Theory Calculations ◽  
Two Dimensional ◽  
Functional Theory ◽  
Donor Acceptor ◽  
Homo And Lumo ◽  
Transfer Properties

We report the synthesis of perylenediimide (PDI)-based ­donor–acceptor hybrids through dissymmetric bay functionalization of PDIs. The dissymmetric bay-functionalized di- and trisubstituted PDIs were characterized by using one- and two-dimensional NMR spectroscopy. Density functional theory calculations revealed (i) an energy gap between the HOMO and LUMO in the range 2.14–2.34 eV, beneficial for charge-transfer properties; and (ii) a twist angle between the two naphthalene units in the range 17–26°, which might be beneficial for disruption of co-facial stacking of the PDI.

Theoretical investigation on vibrational spectroscopic and nonlinear optical activity of 1-(4-chloro phenyl)-3-(4-dimethylamino phenyl) prop-2-en-1-one

2017 ◽  
Vol 95 (4) ◽  
pp. 353-360
Author(s):  
Xiao-Hong Li ◽  
Hong-Ling Cui ◽  
Rui-Zhou Zhang
Keyword(s):  
Density Functional ◽  
Nonlinear Optical ◽  
Energy Gap ◽  
Density Functional Theory Method ◽  
Nbo Analysis ◽  
Frontier Molecular Orbital ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Electron Donation ◽  
Homo Lumo

The density functional theory method was used to calculate the vibrational spectrum, geometrical structure of 1-(4-chloro phenyl)-3-(4-dimethylamino phenyl) prop-2-en-1-one in the ground state. The analysis of natural bond orbital (NBO) was also performed. The infrared spectrum was obtained and interpreted by means of potential energies distributions. NBO analysis shows that electron donation from LP(1)N atom to the anti-bonding acceptor σ*(C6–C12) of the phenyl ring results in the stabilization of 43.9 kJ/mol. The predicted NLO properties show that the βtot of the title compound is larger than that of urea and is a good candidate as a nonlinear optical material. In addition, the frontier molecular orbital is also investigated. The high βtot value and the low HOMO–LUMO energy gap assert the suitability of the grown crystal for NLO applications.

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