A DFT computational study on the molecular mechanism of reaction between methyl 3-hydroxy-3-methyl-2 methylene butanoate and (E)-N-methyl-1-phenylethan-1-imine oxide

In this work we examined the regioselectivity and mechanism the of the cycloaddition reaction of methyl 3-hydroxy-3-methyl-2-methylenebutanoate and (E)-N-methyl-1-phenylethan-1-imine oxide within the DFT. This cycloaddition reaction evolved through non-concerted mechanism. Analysis of the relative free energies associated with the competitive reaction paths shows that the cycloaddition reactions of methyl 3-hydroxy-3-methyl-2-methylenebutanoate and (E)-N-methyl-1-phenylethan-1-imine oxide are highly stereoselective and regioselective, in clear agreement with the experimental outcomes

2D-QSAR evaluation of toxicity of Nitrobenzene derivatives on Tetrahymena Pyriformis using differents statistical methods

With the development of industry and agriculture, an increasing number of nitrobenzenes (NB) are leaking into the environment. Most of these compounds are dangerous and have a high potential to pollute the environment. A quantitative structure-activity relationship (QSAR) study is applied to a set of 50 nitrobenzenes derived molecules to predict the toxicological property on Tetrahymena Pyriformis and to correlate with different physico-chemical parameters. This will be done using principal component analysis (PCA), multiple linear regression (MLR), multiple nonlinear regression (RNLM) and artificial neural network (ANN). The cross-validation (CV-LOO) procedure was used to test the performance of the neural network (ANN)

2D-QSAR studies of isatin based oxadiazole analogs as potent inhibitors of thymidine phosphorylase

The thirty exceptionally potent isatine-based oxadiazole compounds were synthesized and used for the inhibitory potential of thymidine phosphorylase, the determination of the descriptors was determined using marvinsketch, ACD / chemsketch, but the electronic descriptors was determined by Gaussian 09 with B3LYPE base 6-31G (d) and density functional theory (DFT) method to search the quantitative structure-activity relationship (QSAR) with the use of several statistical methods, it begins with principal component analysis the PCA to decrease the number of the descriptors, then one uses the multiple linear regression (RLM) and the nonlinear multiple regression (RNLM). Correlation coefficient values are 0.856  and 0.885 respectively obtained by these statistical methods

The Thermodynamic Aspect, the Temperature and the Solvent effects on the Chemical Reactivity of the Darzens Reaction between Isobutyraldehyde and Isopropyl Dibromoacetate: DFT Study.

The Darzens condensation is used to synthesize α-halogenoglycidic esters which are important compounds permits access to the bioactive molecules. Our aim in this work is to study the temperature effect in the chemical reactivity and in the thermodynamic aspect for the Darzens reaction between isobutyraldehyde and isopropyl dibromoacetate using density functional theory (DFT) on the B3LYP/6-311G (d, p) level. Therefore, we were interested in this study to comparing the ethanol solvent effect with 2-propanol solvent effect. Firstly, we optimized the reagents and products geometries. Secondly, we calculated the HOMO and LUMO energies; the electronic chemical potential; the global electrophilicity and the global nucleophilicity of the reagents; and Gibbs free energy. The local electrophilicity of isobutyraldehyde and local nucleophilicity of isopropyl dibromoacetate are calculated by the Parr function

Discovery of new Sulfur-containing 1,4-naphthoquinone oxime derivatives as anti-MDR cancer agents using 3D QSAR and Docking Methods

Multi-drug resistance (MDR) to anticancer drugs is the primary obstruction to successful treatment of cancer. 3D-QSAR model Comparative Molecular Field Analysis (CoMFA) was used on a series of 1,4-naphthoquinone oxime anti-MDR cancer agents. The CoMFA models used 27 compounds for a training set of 33 compounds reliable values of Q2 (0.586) and R2 (0.923).The statistical results indicate that the experimental results are in good agreement with the predicted values for CoMFA model. the predictive ability of this model was rated by the external validation using a test set of six compounds with predicted determination coefficients R2 test of 0.618, relying on the 3D-QSAR contours, a set of new molecules with high predicted activities were designed. Thus, Surflex-docking approved that predicted molecules in the receptor are stable

Quantum Study of the Reaction Between 2,5-Bis (Pyridin-2-yl) -1,3,4-Thiadiazole and Nickel(II) in the presence of Sodium Azide by Using DFT-B3LYP/6-31G

In the present work we used density functional theory (DFT) with B3LYP/6-31G to study the reaction between 2,5-bis (pyridin-2-yl) -1, 3,4-thiadiazole and sodium azide with nickel(II) triflateby determining theMulliken charges and the energies of the frontier molecular orbitals, chemical potentials, transfer charge quantities, and electrophilicity and nucleophilicity indices. We used the same method to calculate ionisation potentials, electronic affinities, hardness and softness of the various possible organo-metallic complexesobtained in the course of the reaction. We optimised the geometric parameters of the most stable conformers and compared them with those obtained experimentall

Molecular docking and ADMET investigation of a novel series of Pyridinylimidazole derivatives as potential p38α MAP kinase inhibitors

The p38α MAP kinase is a potential therapeutic target for neurodegenerative disorders like Alzheimer's disease. In this study, a dataset of Pyridinylimidazole derivatives was tested against the p38 MAP kinase enzyme using molecular docking and ADMET prediction studies. The objective is to select the most appropriate inhibitors for the p38 MAP kinase enzyme. The findings of molecular docking reveal that the majority of Pyridinylimidazole derivatives exhibit a high affinity for the p38 MAP kinase binding pocket, in comparison to the enzyme's recently approved inhibitor (Neflamapimod). The top-ranked compounds by docking analysis were then evaluated using ADMET prediction. The results show that the Pyridinylimidazole derivatives have acceptable pharmacokinetic properties

Effect of Magnesium on the physicochemical properties of Barium Titanate

In this work the different materials of composition Ba1-xMgxTiO3 (BMxT) (x between 0 and 1) powders were successfully synthesized by the sol-gel method and their structure was characterized by X-ray diffraction. Scanning electron microscopy (SEM) investigation showed an increase in grain size with increasing of Mg content and calcining temperature. Dielectric measurements indicated that when the rate of Mg increases the temperature Tm decreases to the minimum value of 105 ° C around 15% in Magnesiu

DFT, ANN and QSAR studies of quinoline, isoquinoline and quinazoline derivatives against Plasmodium falciparum

In this work, a quantitative structure-activity relationship (QSAR) study was established for 54 derivatives of quinoline, isoquinoline, and quinazoline as novel treatment agents of Plasmodium falciparum Mefloquine (MQ)-resistant and Chloroquine (CQ)-sensitive strain parasite (3D7). Density Functional Theory (DFT) method with the functional B3LYP and 6-311G level set has been used to calculate the quantum molecular descriptors. While the molecular mechanic method (MM2) was carried out to calculate the physicochemical, constitutional, topological and thermodynamic descriptors. Multiple linear regression (MLR), multiple nonlinear regression (MNLR) and artificial neural networks (ANN) methods were explored to build QSAR models. These built models were examined using four validation methods, i.e. leave-one-out (LOO) cross validation, Y-randomization, external validation and applicability domain. The values obtained for the determination coefficient of 0.659, 0.714, and 0.763 by MLR, MNLR and ANN, respectively, show a good predictive quality of the established models. On the basis of a reliable QSAR model, it is possible to design novel compounds with potent anti-Plasmodium falciparum activities

2D-QSAR studies of 3,5-disubstituted indole derivatives as potent Pim1 kinase inhibitors

In a search of newer potent Pim kinase inhibitors, a series of 34 indole derivatives were exhibited to a quantitative structure activity relationship (QSAR) analysis by using multiple linear regression(MLR) and non-linear regression (RNLM), for studying , analysing, and predicting activities the descriptors were determined using Marvin Sketch, ACD/ChemSketch and Gaussian 03. In order to get into chemical property and reactivity informetion of the studied molecules, Density functional theory (DFT) calculations have been carried out using Gaussian 03. The multiple linear regression (MLR) and multiple non-linear regression (MNLR) methods showed a correlation coefficient of 0.79 and 0.82 respectively