A comparative study of deep eutectic solvents based on fatty acids and the effect of water on their intermolecular interactions.

In this work, intermolecular interactions among the species of fatty acids-based DESs with different hydrogen bond acceptors (HBA) in the adjacent water have been investigated using molecular dynamics (MD) simulation. The results of this work provide deep insights into understanding the water stability of the DESs based on thymol and the eutectic mixtures of choline chloride and fatty acids at a temperature of 353.15 K and atmospheric pressure. Stability, hydrogen bond occupancy analysis, and the distribution of the HBA and HBD around each other were attributed to the alkyl chain length of FAs and the type of HBA. Assessed structural properties include the combined distribution functions (CDFs), the radial distribution functions (RDFs), the angular distribution functions (ADFs), and the Hydrogen bonding network between species and Spatial distribution functions (SDF). The reported results show the remarkable role of the strength of the hydrogen bond between THY molecules and fatty acids on the stability of DES in water. The transport properties of molecules in water-eutectic mixtures were analyzed by using the mean square displacement (MSD) of the centers of mass of the species, self-diffusion coefficients, vector reorientation dynamics (VRD) of bonds and the velocity autocorrelation function (VACF) for the center of the mass of species.

Effect of water addition on caprylic acid: Quaternary ammonium salts (QAS) deep eutectic solvents: Characterization of their structural and dynamical properties.

Physicochemical properties of the binary mixtures based on Caprylic acid: Quaternary ammonium salts (QAS) (7:3 mol ratio) are investigated using MD simulations. Considering the hydrophobic character of eutectic solvents based on long-chain fatty acids, the stability of the binary mixtures was investigated in the adjacent water. In order to investigate the effect of water on intermolecular interactions in binary mixtures, the structural properties of the binary mixtures in the pure state and adjacent to water were investigated at 310 K. Assessed structural properties include the combined distribution functions (CDFs), the radial distribution functions (RDFs), the angular distribution functions (ADFs), and the Hydrogen bonding network between HBA and HBD and Spatial distribution functions (SDF). We aimed to represent the structural stability of eutectic solvents based on Caprylic acid and Quaternary ammonium salts (QAS) as a function of the alkyl chain length of cations, the evidence was found for the interaction between the chloride anion leads to the transition of HBA to the water-rich phase. The alkyl chain length of cations of Quaternary ammonium salts shows the stability of eutectic solvents in the adjacent water.

Investigation the effect of water addition on intermolecular interactions of fatty acids-based deep eutectic solvents by molecular dynamics simulations.

In this work, we focused on the interaction between hydrogen bond acceptor (HBA) and hydrogen bond doner (HBD) in the binary mixtures. The results showed that Cl- anion plays a key role in the formation of DESs. Also, the structural stability of deep eutectic solvents based on fatty acids (FAs) and choline chloride (Ch+Cl-) at different ratios was investigated in water using molecular dynamics simulations. We observed that the interaction between the chloride anion and the hydroxyl group of the cation leads to the transition of HBA to the water-rich phase. These atomic sites have important rule in the stability of the eutectic mixtures based on FAs and Cl- anion. However, it seems that the binary mixtures with the mole percent at 30% of [Ch+Cl-] and 70% of FAs have more stability than other ratios.

Copper (II) complexes with N, S donor pyrazole-based ligands as anticancer agents.

A group of bidentate nitrogen and sulfur donor pyrazole derivative ligands abbreviated as Na[RNCS(Pz)], Na[RNCS(PzMe2)], Na[RNCS(PzMe3)], Na[RNCS(PzPhMe)], Na[RNCS(PzPh2)], where (R = Et, Ph), and their Cu (II) complexes were synthesized and characterized by spectroscopic and physicochemical methods. The crystal structure of [Cu(PhNCSPzMe3)2] was determined by X-ray crystallography analysis and the results described a distorted square planar coordination geometry for this complex. Also, the cyclic voltammetry investigations indicated that the synthesized copper complex is an electrochemically active species. Moreover, the cytotoxic activity of all of the twenty synthesized compounds was evaluated using MTT assay against the MCF-7 (human breast carcinoma) cell lines, in vitro. Cu (II) complexes indicate significant cytotoxicity against the MCF-7 cell lines as compared with the free ligands. The docking studies showed that the copper complexes have better interactions with EGFR and CDK2 proteins, compared to the free ligands, and most of the studied compounds have a higher value of binding energy relative to the studied controls. The results of QSAR analysis suggest that dipole moment is in direct correlation with the obtained IC50 values, and it strongly impact the anticancer effects generated by the compounds. Our findings suggest that the developed copper complexes can be good candidates for further evaluations as chemotherapeutic agents in the treatment of cancer.

Electrochemical reduction of NO catalyzed by boron-doped C60 fullerene: a first-principles study.

The electrochemical reduction of nitrogen monoxide (NO) is one of the most promising approaches for converting this harmful gas into useful chemicals. Using density functional theory calculations, the work examines the potential of a single B atom doped C60 fullerene (C59B) for catalytic reduction of NO molecules. The results demonstrate that the NO may be strongly activated over the B atom of C59B, and that the subsequent reduction process can result in the formation of NH3 and N2O molecules at low and high coverages, respectively. Based on the Gibbs free energy diagram, it is inferred that the C59B has excellent catalytic activity for NO reduction at ambient conditions with no potential-limiting. At normal temperature, the efficient interaction between the *NOH and NO species might lead to the spontaneous formation of the N2O molecule. Thus, the findings of this study provide new insights into NO electrochemical reduction on heteroatom doped fullerenes, as well as a unique strategy for fabricating low-cost NO reduction electrocatalysts with high efficiency.

Structural and dynamic properties of eutectic mixtures based on menthol and fatty acids derived from coconut oil: a MD simulation study.

The structural and dynamical properties of the binary mixture of Menthol (MEN) and Fatty acids (FAs) were investigated using molecular dynamics simulations. To this end, the relationship between the structural and dynamical properties of the eutectic mixtures of MEN and FAs with different molar percentages of FAs are studied. Structural properties of the eutectic mixtures were characterized by calculating the combined distribution functions (CDFs), radial distribution functions (RDFs), angular distribution functions (ADFs), hydrogen bonding networks, and spatial distribution functions (SDF). Additionally, our Results indicated robust interactions between menthol and Caprylic acid molecules Finally, the transport properties of the mixtures were investigated using the mean square displacement (MSD) of the centers of mass of the species, self-diffusion coefficients and vector reorientation dynamics (VRD) of bonds. Overall, our simulation results indicated that intermolecular interactions have a significant effect on the dynamic properties of species.

Structure and dynamics of hydrophobic deep eutectic solvents composed from terpene-fatty acids investigated by molecular dynamics simulation.

Hydrophobic deep eutectic solvents (HDES) composed of Terpenes and Fatty acids have recently been the subject of great interest for removing pollutants from an aqueous environment. Despite the specific application of Hydrophobic DES and the important role of molecular dynamics simulation in predicting the properties of these compounds, not many studies have been done on their intermolecular interaction. In this work, we performed molecular dynamics simulations for the eutectic mixture based on monoterpene (Menthol, Thymol) and Fatty acids such as Caprylic Acid, Decanoic Acid, Lauric Acid, and Myristic acid. Binary mixtures of Terpene and Fatty acids were prepared at molar ratios 1:1, and their properties were investigated at 323 K. We have carried out 50 ns in the ensemble NPT to understand thermo-physical properties that are largely dependent on the interaction between molecules. Here, the structural properties of the binary mixtures were evaluated, and the possible explanations for their thermo-physical properties have been presented. The interaction between Terpenes and Fatty acids was studied by the structural properties such as the atom-atom radial distribution functions (RDF) and the Hydrogen bonding network between species and Spatial distribution functions (SDF). The structural properties studies revealed that the interaction between Terpenes and Fatty acids decreased the reduction of the accumulation of Terpene molecules around each other in the binary mixtures. Evidence has been acquired that the interaction between the menthol molecules was mostly affected by the Fatty acids molecules. Also, the transport properties of the binary mixtures were explored using the mean-square displacement (MSD) for the centers of mass of molecules, self-diffusion of species, and vector reorientation dynamics (VRD) of bonds. The simulation results indicated that intermolecular interactions play an important role in the dynamic properties of species, and maintains the low melting point of the mixture.

Influence of curcumin and rosmarinic acid on disrupting the general properties of Alpha-Synuclein oligomer: Molecular dynamics simulation.

Alpha-Synuclein (αS) is a protein involved in Parkinson's disease (PD) and is probably the main cause of the pathology of the disease. During pathogenesis, αS monomers aggregate, leading to the formation of a variety of oligomeric species. Recent research studies suggest that the oligomeric toxic species may be one of the main processes for pathology and disease. Here, we studied influence of two natural polyphenolic compounds, Curcumin (CUR) and Rosmarinic acid (RA), on disrupting the general properties of αS oligomer by molecular dynamics (MD) simulation method. The hydrophobic central domain of αS (NAC), is the most essential district responsible for protein self-aggregation; so, in this study, our systems have been developed to form a quintuplet NAC region of αS called 5mer; they have 10 and 20 CUR and RA molecules and a 5mer with no ligand. The several important and efficient analyzes were performed to investigate the effect of ligands on the structural properties of αS oligomers. The results indicated that both ligands can be successful in disrupting the original structure of αS oligomers; therefore, they can be considered suitable candidates for designing Parkinson's drugs.

Insights into the interactions and dynamics of a DES formed by phenyl propionic acid and choline chloride.

Deep eutectic solvents (DESs) have received much attention in modern green chemistry as inexpensive and easy to handle analogous ionic liquids. This work employed molecular dynamics techniques to investigate the structure and dynamics of a DES system composed of choline chloride and phenyl propionic acid as a hydrogen bond donor and acceptor, respectively. Dynamical parameters such as mean square displacement, liquid phase self-diffusion coefficient and viscosity are calculated at the pressure of 0.1 MPa and temperatures 293, 321 and 400 K. The system size effect on the self-diffusion coefficient of DES species was also examined. Structural parameters such as liquid phase densities, hydrogen bonds, molecular dipole moment of species, and radial and spatial distribution functions (RDF and SDF) were investigated. The viscosity of the studied system was compared with the experimental values recently reported in the literature. A good agreement was observed between simulated and experimental values. The electrostatic and van der Waals nonbonding interaction energies between species were also evaluated and interpreted in terms of temperature. These investigations could play a vital role in the future development of these designer solvents.