DFT Studies and Quantum Chemical Calculations of Benzoyl Thiourea Derivatives Linked with Morpholine and Piperidine for the Evaluation of Antifungal Activity

2022 ◽  
Vol 12 ◽  
Author(s):  
Rameshwar K. Dongare ◽  
Shaukatali N. Inamdar ◽  
Radhakrishnan M. Tigote
Keyword(s):  
Antifungal Activity ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Density Functional ◽  
Basis Set ◽  
Functional Study ◽  
Chemical Parameters ◽  
Thiourea Derivatives ◽  
Quantum Chemical Parameters ◽  
B3lyp Method

Herein, we report the density functional study of benzoyl thiourea derivatives linked to morpholine and piperidine to evaluate their antifungal activity. Overall six compounds BTP 1-3 and BTM 4-6 were optimized with DFT using the B3LYP method with 6-31G(d,p) basis set. The molecular geometry, bond lengths, bond angles, atomic charges and HOMO-LUMO energy gap have been investigated. The structural parameters have been compared with the reported experimental results and structure- antifungal activity relationship is explored in details. The calculated results from DFT were discussed using all Quantum chemical parameters of the compounds. Introduction: Benzoyl thiourea derivatives linked with morpholine and piperidine were reported to have good antifungal activity. Objective: To find the correlations between the quantum chemical calculations and the antifungal activity for the benzoyl thiourea derivatives linked with morpholine and piperidine. Method: Optimization was carried out with DFT using B3LYP method utilizing 6-31G(d,p) basis set. Results: A good correlation between the quantum chemical calculations and the antifungal activity for the benzoyl thiourea derivatives linked with morpholine and piperidine was found. Conclusion: The DFT study of benzoyl thiourea derivatives linked to morpholine and piperidine was evaluated for their antifungal activity and it showed good correlations of activity with the quantum chemical parameters.

Molecular and Electronic Structure of 1-Naphtol : Ab Initio Molecular Orbital and Density Functional Study

2011 ◽  
Vol 110-116 ◽  
pp. 1862-1869
Author(s):  
G. Raja ◽  
K. Saravanan ◽  
S. Sivakumar
Keyword(s):  
Ab Initio ◽  
Quantum Chemical Calculations ◽  
Raman Spectra ◽  
Quantum Chemical ◽  
Density Functional ◽  
Computational Method ◽  
Basis Set ◽  
Mode Analysis ◽  
Functional Study ◽  
Infrared And Raman Spectra

The molecular vibrations of 1-Naphtol were investigated in polycrystalline sample, at room temperature, by FT- IR and FT-Raman spectroscopy. In parallel, ab initio and various density functional (DFT) methods were used to determine the geometrical, energetic and vibrational characteristics of 1-Naphtol . On the basis of B3LYP/6-31G* and B3LYP/6-311+G** methods and basis set combinations, a xnormal mode analysis was performed to assign the various fundamental frequencies according to the total energy distribution (TED). The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The Infrared and Raman spectra were also predicted from the calculated intensities. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. Simulation of Infrared and Raman spectra, utilizing the results of these calculations led to excellent overall agreement with observed spectral patterns. The investigation is performed using quantum chemical calculations conducted by means of the Gaussian 98W and Guassview set of programs. Further, density functional theory (DFT) combined with quantum chemical calculations to determine the first-order hyperpolarizability.

scholarly journals SYNTHESIS, STRUCTURE, TAUTOMERISM AND INVESTIGATION OF SOME QUANTUM CHEMICAL PARAMETERS OF COMPOUND 2-(4,6-DIOXO-1,3,5-TRIAZINAN-2- YLIDENE)HYDRAZINECARBOXYAMIDE

2020 ◽  
Vol 5 (7(76)) ◽  
pp. 65-68
Author(s):  
Bakhtiyor Ganiyev ◽  
Bako Umarov ◽  
Gulyayra Kholikova ◽  
Furqat Salimov ◽  
Ferangiz Aslonova
Keyword(s):  
Density Functional Theory ◽  
Quantum Chemical Calculations ◽  
Elemental Analysis ◽  
Quantum Chemical ◽  
Density Functional ◽  
Chemical Parameters ◽  
Dft Methods ◽  
Functional Theory ◽  
Quantum Chemical Parameters ◽  
Composite Methods

This article describes the synthesis and tautomerism of 2- (4,6-dioxo-1,3,5-triazinan-2-ylidene) hydrazinecarboxyamide. The synthesized compound was investigated using elemental analysis methods, and quantum chemical calculations performed in ChemCraft 1.8 and Gaussian programs. Composite methods of the Gaussian family (G4) and density functional theory (DFT) methods (BLYP / 6-311 + G (d, p)) were used. The data obtained indicate that the BLYP / 6-311 + G (d, p) well suited for describing such systems in order to save 66 machine resources. Based on the calculated resistance series, it was established that the main form is diketoenolform.

Density Functional Study on the Configurations of Nen (n=2~36) Clusters

2017 ◽  
Vol 727 ◽  
pp. 381-387
Author(s):  
Chang Ning Peng ◽  
Xing Rong Zheng
Keyword(s):  
Binding Energy ◽  
Density Functional ◽  
Energy Gap ◽  
Geometry Optimization ◽  
Basis Set ◽  
Functional Study ◽  
B3lyp Method ◽  
The Density Functional Theory ◽  
Quantum Chemistry Calculations ◽  
Average Bond

Based on the First-principles and the method of quantum chemistry calculations, using the B3LYP method and 6-31G basis set of the density functional theory (DFT), the configurations and binding energy of Nen (n=2~36) clusters are calculated and studied theoretically after the calculation of geometry optimization. By changing the atomic number n of the Nen (n=2~36) clusters, it obtained that the stable structures, the binding energy and HOMO - LUMO energy gap of the Nen (n=2~36) clusters under the same ideal conditions, and summarizes the change rule of the stable configurations, the binding energy and the average bond length of the Nen (n=2~36) clusters.

Synthesis and DFT Quantum Chemical Calculations of 2-Oxopyrimidin-1(2H)-yl-Urea and Thiorea Derivatives

2019 ◽  
Vol 41 (5) ◽  
pp. 841-841
Author(s):  
Murat Saracoglu Murat Saracoglu ◽  
Zulbiye Kokbudak Zulbiye Kokbudak ◽  
Esra Yalcin and Fatma Kandemirli Esra Yalcin and Fatma Kandemirli
Keyword(s):  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Chemical Potential ◽  
Energy Gap ◽  
Basis Set ◽  
Chemical Hardness ◽  
Spectroscopic Techniques ◽  
Solvent Phase ◽  
B3lyp Method ◽  
Homo Lumo

A series of the new 2-oxopyrimidin-1(2H)-yl-urea (3a-c) and thiourea (4a-d) derivatives were synthesized by the reaction of arylisocyanates (2a-c) or arylisothiocyanates (2d-g) and the 1-amino-5-(4-methoxybenzoyl)-4-(4-methoxyphenyl)pyrimidin-2(1H)-one (1). The structures of the compounds 3a-c and 4a-d were characterized by elemental analysis, FT-IR, 1H and 13C-NMR spectroscopic techniques. In addition to experimental study in order to find molecular properties, quantum-chemical calculations of the synthesized compounds were carried out by using DFT/B3LYP method with basis set of the 6-311G(d,p). Quantum chemical features such as HOMO, LUMO, HOMO-LUMO energy gap, Ionization potential, chemical hardness, chemical softness, electronegativity, chemical potential, dipole moment etc. values for gas and solvent phase of neutral molecules were calculated and discussed.

Thiadiazole-2-Thiol-5-Thione and 2,5-Dimercapto-1,3,4-Thiadiazol Tautomerism, Conformational Stability, Vibrational Assignments, Inhibitor Efficiency and Quantum Chemical Calculations

2020 ◽  
Vol 234 (3) ◽  
pp. 415-440 ◽  
Author(s):  
Muhammad H. Esmaiel ◽  
Hany A. Basuony ◽  
Mohamed K. Al-Nawasany ◽  
Musab M. Shulkamy ◽  
Ibrahim A. Shaaban ◽  
...  
Keyword(s):  
Solid State ◽  
Potential Energy ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Density Functional ◽  
Solid Phase ◽  
Thiol Group ◽  
Basis Set ◽  
Basis Sets ◽  
Vibrational Assignments

AbstractRaman (3700–100 cm−1) and infrared (4000–400 cm−1) spectra of 2,5-Dimercapto-1,3,4-thiadiazol (DMTD) were recorded in the solid phase. Six structures (1–6) were initially proposed for DMTD as a result of thiol-thione tautomerism and internal rotation(s) of thiol group(s) around the C–S bond. Quantum chemical calculations were carried out for an isolated molecule (1–6) using density functional theory (B3LYP) and ab initio MP2(full) methods utilizing 6-31G(d) and 6-311++G(d,p) basis sets which favor thiol-thione tautomerism (structure 4). Relaxed potential energy surface scans of structure 4 revealed an additional conformer (the thiol group is out-of-plane, structure 7) using the aforementioned methods at 6-311++G(d,p) basis set. For additional verification, plane-wave solid state calculations were carried out at PW91 and PBEsol came out in favor of conformer 7. This is in agreement with the computed/observed SH in-plane bending of S-7 (959/941 cm−1) rather than the one estimated at (880 cm−1) for S-4. Moreover, the observed split IR/Raman bands were found consistent with solid state calculated frequencies of S-7 assuming two molecules per unit cell bonded via H-bonding intermolecular interactions. Aided by vibrational frequency calculations, normal coordinate analysis, force constants and potential energy distributions (PEDs), a complete vibrational assignment for the observed IR and Raman bands is proposed herein. Furthermore, we have estimated the frontier molecular orbitals and atomic charges to account for the corrosion inhibition efficiency of DMTD along with its binding sites to the metal surface. Our results are discussed herein and compared to similar molecules whenever appropriate.

scholarly journals Quantum Chemical Studies on the Inhibiting Effect of Bipyrazoles on Steel Corrosion in HCl

2010 ◽  
Vol 7 (2) ◽  
pp. 419-424 ◽  
Author(s):  
K. Laarej ◽  
M. Bouachrine ◽  
S. Radi ◽  
S. Kertit ◽  
B. Hammouti
Keyword(s):  
Molecular Orbital ◽  
Quantum Chemical ◽  
Density Functional ◽  
Steel Corrosion ◽  
Chemical Parameters ◽  
Quantum Chemical Parameters ◽  
Highest Occupied Molecular Orbital ◽  
Chemical Studies ◽  
Quantum Chemical Studies ◽  
Lowest Unoccupied Molecular Orbital

Correlation of the efficacy of some bipyrazoles,N,N-bis(3,5-dimethyl-pyrazol-1-ylmethyl)-cyclohexylamine (Bip 1),N,N-bis(3,5-dimethylpyrazol-1-ylmethyl)-ethanolamine (Bip 2),N,N-bis(3,5-dimethylpyrazol-1-ylmethyl) allylamine (Bip 3) andN,N-bis(3-carboethoxy-5-methylpyrazol-1-ylmethyl)-cyclohexylamine (Bip 4), against the corrosion of mild steel in HCl is discussed using density functional approach B3LYP/6-31G(d) calculations. The bipyrazole inhibitors exhibited the highest inhibition efficiency. The quantum chemical parameters calculated are, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), the gap energy (ΔE), the dipole moment (μ), the softness (σ) and the total energy (TE).

scholarly journals Prediction of the Corrosion Inhibition Efficiency of Imidazole Derivatives: A Quantum Chemical Study

2019 ◽  
Vol 2 (1) ◽  
pp. 88
Author(s):  
Saprizal Hadisaputra ◽  
Zohrul Iskandar ◽  
Dina Asnawati
Keyword(s):  
Corrosion Inhibition ◽  
Quantum Chemical ◽  
Density Functional ◽  
Inhibition Efficiency ◽  
Quantum Chemical Study ◽  
Density Functional Theory Method ◽  
Chemical Parameters ◽  
Imidazole Derivatives ◽  
Quantum Chemical Parameters ◽  
Corrosion Inhibition Efficiency

This study aims to determine the the efficiency of corrosion inhibition of imidazole derivatives in carbon steel based on quantum chemical parameters. Density functional theory method was applied in this study. Corrosion inhibition efficiency values ​​are strongly influenced by substituent groups. Corrosion inhibition efficiency values ​​have a linear correlation with quantum chemical parameters. The amine substituent increased the value of corrosion inhibition efficiency, in contrast nitro group reduced the efficiency of corrosion inhibition. The predicted corrosion inhibition efficiency data of imidazole does agree with the experimental data.  

scholarly journals Synthesis, Characterization and Theoretical Insights into Molecular Properties of 2-(4-fluorophenyl)-4H-chromen-4-one

2021 ◽  
Vol 7 (2) ◽  
pp. 721-724
Author(s):  
Rohit S. Shinde
Keyword(s):  
Density Functional ◽  
Molecular Electrostatic Potential ◽  
Biologically Active ◽  
Basis Set ◽  
Chemical Parameters ◽  
Functional Theory ◽  
Quantum Chemical Parameters ◽  
Chemical Behaviour ◽  
Title Molecule ◽  
Homo Lumo

Flavone scaffold is one of the most often perceived parts in biologically active organic compounds. In light of this, a flavone; 2-(4-fluorophenyl)-4H-chromen-4-one (FPC) has been synthesized, characterized and studied by using density functional theory (DFT) at B3LYP/6-31G(d,p) basis set. The geometry of the FPC molecules has been optimized by using B3LYP/6-31G(d,p) basis set and in-depth structural analysis on bond lengths and bond angles has been discussed. The HOMO-LUMO analysis and various quantum chemical parameters are computed and discussed for the better understanding of chemical behaviour of the title molecule. Molecular electrostatic potential (MEP) surface investigation is presented to understand the reactivity sites of the title molecule.

VIBRATIONAL SPECTROSCOPIC INVESTIGATION AND CONFORMATIONAL ANALYSIS OF 1-PENTYLAMINE: A COMPARATIVE DENSITY FUNCTIONAL STUDY

2010 ◽  
Vol 09 (03) ◽  
pp. 667-685 ◽  
Author(s):  
ÖZGÜR ALVER ◽  
CEMAL PARLAK
Keyword(s):  
Density Functional ◽  
Density Functional Method ◽  
Absolute Error ◽  
Functional Method ◽  
Basis Set ◽  
Functional Study ◽  
Stable Form ◽  
Water Solvent ◽  
B3lyp Method ◽  
Ft Ir

The possible stable conformers of 1-pentylamine (1-pa) molecule were experimentally and theoretically studied by FT-IR and Raman spectroscopy in the region of 4000–400 cm-1. The optimized geometric structures concerning the minimum on the potential energy surface were investigated by Becke-3–Lee–Yang–Parr (B3LYP) density functional method together with 6-31G(d) basis set. Based on the energy calculations, 10 possible rotamers of 1-pa (TT, TG, GT, GT1, GG1, GG2, GG3, GG4, GG5 and GG6; T and G denote trans and gauge, respectively) were proposed. Optimized energies of the possible conformers were obtained in the gas phase and within the chloroform, carbon tetrachloride, methanol and water solvent environments all of which have different polarities. Comparison between the experimental and theoretical results based on the correlation graphics and mean absolute error calculations presented in this study indicates that density functional B3LYP method is able to provide satisfactory results for predicting vibrational wavenumbers and TT isomer is the most stable form of 1-pa molecule.

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