Molecular docking studies,structural and spectroscopic properties of monomeric and dimeric species of benzofuran-carboxylic acids derivatives: DFT calculations and biological activities

Structural optimization, molecular docking analysis, electronic and vibrational properties have been investigated for the 1-benzofuran-2-carboxylic acid (2BF) and 1-benzofuran-3-carboxylic acid (3BF) using DFT/B3LYP/6-311++G(d,p) level of theory. The theoretical parameters have a very good consistency with the experimental ones. The weak intermolecular interactions were analyzed by different tool such as: Hirshfeld surfaces, topological analysis and natural bond orbital studies. The nonlinear optical properties have been investigated. Molecular electrostatic potential and frontier molecular orbitals (FMOs) analysis have been carried out to understand the reactivity of the molecule. In addition, TD-DFT calculation is initiated to simulate the UV–vis absorption spectrum and to determine several important electronic properties like HOMO-LUMO gap energy and electronic transitions. The complete vibrational assignments and the force constants were reported for monomer and dimers of both acids. The biological activities of the tow acids have been studied via molecular docking analysis. The later calculations prove that the studied acids have an inhibitor effect against cancer and microbial diseases.     

Theoretical evaluation to improve the performance of composite wax powder: cooperativity effects involving the strong Na+···π/σ and weak hydrogen-bonding interactions in the complex of graphene oxide with Na+ and CH4

ABSTRACT

To provide a reasonable design scheme to improve the performance of composite wax powder, the ternary complex Na⁺···graphene oxide (GO)···CH₄ was selected as a model system to evaluate the cooperativity effect between the Na⁺···σ/π and H-bonding interactions in the composite wax powder doped with GO at the M06-2X/6-311++G(2d,p) and MP2/6-311++G(2d,p) levels. The cooperativities in GO···(CH₄)_n (n?=?1～10) and thermodynamic cooperativity effects in Na⁺···GO···CH₄ were also investigated. Although the changes of the absolute values of H-bonding interactions were slight, from those of relative values, the influence of the Na⁺···π or Na⁺···O interaction on the C–H···π, O–H···C or C–H···O interaction was notable upon the formation of ternary systems. The anti-cooperativity effect was found in the cyclic structure, while the cooperativity effect appeared in the linear conformation. The Na⁺···σ/π and H-bonding interactions as well as cooperativities in Na⁺···GO···CH₄ were stronger than those in Na⁺···coronene···CH₄. The formation of Na⁺···GO···CH₄ is a thermodynamic cooperativity process driven by the enthalpy change. Therefore, it could be inferred that, when graphite powder or carbon black was replaced by GO, the compatibilities could be strengthened among various components, and thus the performance of casting moulds could be improved. Atoms-in-molecules (AIM) and reduced density gradient (RDG) analyses confirmed the cooperativity effect and revealed the nature of the improved performance of composite wax powder with GO. The GO···(CH₄)_n (n?=?1～3) are positively cooperative, while the negative cooperativity is shown when n?=?4～10.     

Tuning of tetrel bonds interactions by substitution and cooperative effects in XH3Si···NCH···HM (X = H,F, Cl,Br; M = Li,Na, BeH and MgH) complexes

In this work, the interplay between the tetrel bond and the dihydrogen bond is investigated in ternary XH₃Si···NCH···HM complexes, where X = H, F, Cl, Br and M = Li, Na, BeH, MgH. The nature of Si···N and H···H interactions is studied by molecular electrostatic potential (MEP), noncovalent interaction and electron localisation function analyses. All binding distances in the ternary complexes are shorter than those of isolated XH₃Si···NCH and NCH···HM systems. That is, the two types of interactions have a cooperative effect on each other. The results of the MEP analysis indicate that the enhancement of the Si···N and H···H bonds can mainly be attributed to the electrostatic interaction. The plot of the reduced density gradient versus sign (λ₂)ρ indicates that the location of the spike associated with each interaction in the ternary systems moves slightly towards the negative (λ₂)ρ values with respect to the binary systems. This confirms that both Si···N and H···H interactions in the ternary complexes are strengthened by the presence of other. Besides, cooperative effects lead to a considerable change in the ¹⁴N nuclear quadrupole coupling constant values of the ternary complexes relative to the XH₃Si···NCH complexes.     

Fluorines in tetrafluoromethane as halogen bond donors: Revisiting address the nature of the fluorine's σhole

It has been demonstrated in several instances that the 0.001 a.u. (electrons per bohr³) isodensity mapped electrostatic surface potentials on the fluorines along the outermost extensions of the C? F covalent bonds in tetrafluoromethane (CF₄) are entirely negative, they are thereby unable to engage in σ_hole bonding interactions with the negative sites on another molecules. In this study, we have attempted at resolving this controversy by performing various high‐level electronic structure calculations with Quadratic Configuration Integrals of Singles and Doubles QCISD(full), second‐order Møller–Plesset MP2(full), and 12 other Density Functional Theory (DFT) based functionals with and without dispersion corrections, all in conjunction with the 6–311++G(2d,2p) basis set. The results achieved with all the levels of theory utilized suggest that the fluorine's σ_holes in CF₄ are positive regardless of the 0.001‐, 0.0015‐, and 0.002‐a.u. isodensity mapped electrostatic surfaces examined. Because of this specific quality, the fluorines in CF₄ have displayed their capacities to form not only 1:1 clusters with the Lewis bases such as water (H₂O), ammonia (NH₃), formaldehyde (H₂C?O), hydrogen fluoride (HF), and hydrogen cyanide (HCN), but also 1:2, 1:3, and 1:4 clusters with the latter three randomly chosen Lewis bases. Various topological and nontopological features obtained from applications of atoms in molecules, noncovalent interaction reduced‐density‐gradient and natural bond orbital analytical tools reveal that the N···F, O···F, and F···F long‐ranged interactions developed between the interacting monomers in H₃N···FCF₃, H₂O···FCF₃, and (Y? D)_n=1–4···F₄C (Y? D = H₂C?O, HCN, and HF) are reminiscent of halogen bonding. The nonadditive cooperative and anticooperative energetic effects emerged on cluster formations are discussed in detail. © 2015 Wiley Periodicals, Inc.     

Molecular Recognition of Pyromellitic Imide-azacyclophane to Organic Pollutant

Anion can be identified by pyromellitic imide-azacyclophane which is one of the host compounds.This article investigated the interaction between the host and organic pollution compounds.The host and other eight compounds were optimized by DFT(density functional theory) B3LYP/6-31G level and the energy of compounds was corrected using Boys-Bemardi method.On the basis of B3LYP/6-31G optimized geometries,the RDG function and sign(λ2(r))ρ(r) function values of space points were calculated,and color RDG isosurface map was drawn.3He chemical shift was calculated by the B3LYP/6-31G method.The results showed that the eight organic pollution molecules with the host one shaped stable configurations by hydrogen bonds,respectively.The stabilization energy of complexes 4 and 7 showed repulsion(steric effects) of cyclophane cage observably affecting the stability of the complexes.The location,intensity and the type of interaction in complex 1 were analyzed through color-filled RDG isosurface map.Aromaticity calculations showed that the weak interaction reduced the transverse induction ring current in the host rings,and deteriorated the aromaticity of compounds.     

Spectral characterizations,molecular docking analysis and quantum computational calculations of 4-hydroxy-3-nitrobenzaldehyde

The FT-IR, FT-Raman, UV–Vis and NMR spectra of 4-Hydroxy-3-nitrobenzaldehyde (4H3NB) were examined by the hybrid correlation approach. B3LYP method with 6–311++G(d,p) basis set were utilised to obtain the ideal molecule form, vibrational wavenumbers, Raman activities and infrared intensities. The vibrational spectra's detailed interpretation was to be provided by the MOLVIB software. Bonding orbitals participate in all stages of natural bond orbital (NBO) analysis as donors and acceptors, which stabilises molecules through intermolecular charge transfer. Electron localization function (ELF) and localised orbital locator (LOL) maps were used to create 4H3NB and have topological properties. The title molecule's interactions were examined via reduced density gradient (RDG) evaluation. Molecular docking research was used to foreseen the binding interactions of 4H3NB derivative with the estrogen receptor 4-hydroxybenzaldehyde. Auto-dock software was used to conduct receptor-ligand docking investigation. According to the molecular docking results, the highest mean negative binding affinity (−6.718 kcal/mol) was exhibited by the current chemical.