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The impact of molybdenum (Mo) and tungsten (W) on improving the catalytic characteristics of the chromium-based catalyst, Cr2O3, was explored in this study. The use of semi-empirical and density functional theory computational methods was deployed to understand the impact of the substitution of the chromium (Cr) with Mo and W on the catalyst, CrXO3 (where X = Cr, Mo, W) in the production of propylene from propane. Findings from the investigation confirmed that the surface modified with Mo showed better potential for improving the catalyst selectivity, retarding propylene dehydrogenation, cracking, and coking path than W, which offered a lower selectivity. The use of Mo was found to have better facilitated the propylene production due to its lower affinity for coke and cracking promoting adsorbates accounted for its sites, including easier desorption of propylene and higher barrier of deep dehydrogenation for preventing the production of undesired products, unlike the use of W. This study, therefore, recommends the use of Mo for the improvement of the catalyst that could result in better propylene yield, which could aid in meeting its rising market demand., S ciljem poboljšanja karakteristika katalizatora na bazi kroma, u ovom su se istraživanju kombinirano primijenile poluempirijske računalne metode i metode temeljene na teoriji funkcionala gustoće. Nastojao se dobiti uvid u katalitički potencijal izmjene kroma molibdenom i volframom u katalizatoru CrXO3 (gdje X označava krom, molibden i volfram) za dehidrogeniranje propana pri proizvodnji propilena. Rezultati su potvrdili da površina modificirana molibdenom pokazuje bolju selektivnosti u usporedbi s površinom modificiranom volframom, usporavajući dehidrogenaciju, pucanje i koksiranje propilena. Utvrđeno je da upotreba molibdena olakšava proizvodnju propilena zbog njegova nižeg afiniteta prema adsorbatima koji potiču pucanje i koksiranje, uključujući i lakšu desorpciju propilena te višu barijeru potpune dehidrogenacije što sprječava nastanak neželjenih produkata; to nije bio slučaj kod volframa. Ovo istraživanje stoga preporučuje upotrebu molibdena za poboljšanje svojstava katalizatora, što bi moglo rezultirati većim iskorištenjem u proizvodnji propilena te pomoći zadovoljavanju rastuće tržišne potražnje za propilenom.

The resistance of the P. falciparum strain to some of the antimalarial drugs has been a dominant dilemma facing the treatment of this fetid disease. This necessitates the detection and development of new antimalarial agents targeting the P. falciparum. Azetidine-2-carbonitriles reported for its antimalarial activities, could provide an alternative to the customized antimalarial drugs. Leading to the use of quantitative structure-activity relationship (QSAR) studies, which relates the structures of Azetidine-2-carbonitriles with their activities to generate predictive models. The structures were optimized using density functional theory (DFT) DFT/B3LYP/6-31G* basis set to generate their molecular descriptors, where five predictive models were constructed using the generated descriptors. The models were constructed using the genetic function algorithm component of a material studio, where the model with good statistical parameters, high coefficient of determination (R2) = 0.9465, cross-validated R2 (Q2cv) = 0.8981, Q2 (L4O)cv = 0.9272, and highest external validated R2 (R2pred) = 0.6915 was selected as the best model. These statistical results show the robustness, excellent power of prediction, and validity of the selected model. The descriptor, SpMax2_Bhp (the maximum absolute eigenvalue of Barysz matrix for n = 2 was weighted by polarizability), was revealed to be the most influential in the model due to its highest mean effect. The descriptor played a role in the design of sixteen (16) theoretical derivatives of Azetidine-2-carbonitriles using compound 25 as the design template by increasing polarizability of the compounds through substitution of the various group with electron deactivating groups (F, I, Cl, SO3H, CN, NO2, etc.) at different position of the template. The designed compounds were docked with Plasmodium falciparum dihydroorotate dehydrogenase (Pf-DHODH), giving compound D9 the highest binding energy. The designed compounds were further screened for their drug-likeness, where they all pass Lipinski’s RO5. All the compounds show good skin permeability coefficient and have low Gastrointestinal absorption while few compounds D1, D2, D3, D14, and D15 inhibiting the CYP1A2.

Lung cancer remains the leading and deadly type of cancers worldwide. It was estimated to account for about 25% of the 7 million people that died as a result of cancer-related illness every year in the world. In silico/structure-based approach was used to design nine (9) new non-small cell lung cancer (NSCLC) drugs using molecule 22 (as template for the design) identified with the best binding affinity previously reported in our work. The anti- proliferative activity of these newly designed NSCLC drugs was predicted using the best model reported in our previous work and found have better anti-proliferative activities than that of the hit compound with antiproliferative activity of 6.069 except for compounds SCD 3, SCD 6 and SCD 7 respectively. Molecular docking was studied to investigate and explore the mode of binding of these newly designed NSCLC drugs with the active site of epidermal growth factor receptor (EGFR) kinase enzyme and found have better affinities(between 10.5 kcal/mole to 11.0 kcal/mole) than the template (molecule 22) with a binding affinity of 10.4 kcal/mole and the control gefitinib with a binding affinity of - 8.0 kcal/mole, respectively. None of them was found to have more than one violation of the filtering criterion used in this study which confirms their oral bioavailability with good ADMET properties. The modeled anti-proliferative activities and binding affinities of these newly designed NSCLC drugs were found to be better than that of the template (Molecule 22) and the control (Gefitinib) used in this study. They werealso found to be non-toxic with good pharmacokinetic properties.

The knowledge of atmospheric chemistry has explained several reactions that occur in atmosphere regarding volatile organic compounds (VOCs). In this original paper, computational kinetic study was carried out on atmospheric oxidation reaction mechanism of 1-fluoro-2-methoxypropane (CH3CH(OCH3)CFH2) with OH/ClO radicals using DFT/M06-2X/6–311++G∗∗ method. To improve the results, DFT/M06-2X/6–311++G(2df,2p) single-point calculations were performed on the reacting species involved. The Monte Carlo search on the investigating hydrofluoroether (H3CCH(OCH3)CFH2) showed nine conformers with the lowest global minimum conformer being considered for this study. The reaction proceeded via four (4) reaction routes which led to dehydrogenation in each cases of the radical (OH/ClO) used. The total rate for dehydrogenation reaction of H3CCH(OCH3)CFH2 with OH/ClO radicals is 9.13 ∗ 103 s−1 and 1.23 ∗ 106 s−1 at 298 K which is in agreement with the available experimental rates recorded by Healthfield et al. (1998), Kazuaki Tokuhashi et al. (2000). Also, in each radical cases, thermodynamics parameters, the major and minor products’ heat of formation were computed with potential energy surfaces (PES) for the reactions constructed at absolute temperature of 298 K. Keywords: 1-fluoro-2-methoxypropane, Density functional theory, Ozone depletion, Hydrofluoroethers (HFEs), OH & ClO radicals

Additional file 1. Table 1. Training sets and activity. Table 2. Test sets activity.

Additional file 1: Table S1. Chemical structures of iminoguanidine compounds as well as their activity levels. Table S2. The regression statistics of the 2D-QSAR equations. Table S3. Experimental endpoint and predicted pMIC50 values of training and test set compounds by Model 1 equation. Table S4. The binding affinity score of each ligand and standards in SARS-CoV-2 virus and pseudomonas aeruginosa using the Autodock vina with PyRx program.

Additional file 2: Figure S1. The plot of experimental endpoint vs predicted pMIC50 by model equation. Figure S2. The plot of experimental endpoint vs predicted pMIC50 LOO. Figure S3. View residuals calculated using predictions by model equation. Figure S4. View Residuals calculated using predictions by LOO. Figure S5. Using h* = 0.5 as the warning leverage, the plot of standardized residuals versus hat values (William plot). Figure S6. Using h* = 0.5 as the warning leverage, the plot of standardized residuals versus hat values (William plot – Prediction by LOO). Figure S7. Insubria Graph for the applicability domain inspection of the developed model. Figure S8. Leave-two-out cross validation vs Kxy. Figure S9. Plot of Y-scrambled validations models compared with the original model. Figure S10. Y-randomization validation procedure to verify chance correlation of a model using QSAR modeling. Figure S11. Quality verification plot of the energy minimized model of the19-fatty acid desaturase performed using ERRAT.

CFCs containing volatile compounds are detrimental to atmospheric environment and to all living organisms. These compounds are frequently reported to be chemically stable/inert. Also their photodissociation reaction results to reasonable amount of Chlorine atoms formation in the stratospheric part of atmosphere. This eventually bring out depletion of Ozone (lives and properties protecting compound) in the stratosphere. In order to cope this environmental havoc, there is need to find substitutable compounds for CFCs and possibly predict their atmospheric effects. Ethers when fluorinated can serve as CFCs substitute. Therefore, in this work, an Insilco investigation was conducted on the thermochemistry, mechanism and kinetics of the Hydrogen abstraction reactions of partially fluorinated isopropyl methyl ether (1-fluoro-2-methoxypropane i.e. (CH2FCH(OCH3)CH3)) with Bromine monoxide radical (BrO.) using the Density Functional Theory (DFT) based M06-2X/6-311++G** strategy. To computationally refine/improve the energy data, the single-point calculations (DFT/M06-2X/6-311++G(2df,2p) were immediately executed on the reacting species involved. The Monte Carlo search on the investigating CH2FCH(OCH3)CH3 showed nine conformers with the lowest global minimum configuration being studied. The results of this investigation showed that the atmospheric oxidation reaction of CH2FCH(OCH3)CH3 with the BrO radical proceeded in four (4) plausible reaction routes. The computed total theoretical rate of 7.95*〖10〗^(-11) M-1 sec-1, the first of its kind with BrO radical was recorded. The atmospheric lifetime/global warming potential of 1.35*10-2 days/72.8 were also reported. The potential energy surface (PES) for each reaction route with the BrO radical was constructed at absolute temperature of 298.15 K.

Additional file 1. Table S1. Chemical structures of the study compounds. Table S2. The descriptor used in the model and their descriptions. Table S3. Numerical values of the descriptor used in the selected model. Table S4. Chemical Structure, predicted pEC50, leverage values, and MolDock scores of template molecule (T), designed molecules (N), and reference Molecule (R).

Quantitative Structure Activity Relationship (QSAR) and molecular Docking studies were carried out on some novel compounds to generate a good QSAR models that relate the anti-breast cancer activity values with the molecular structure of the compounds. Genetic Function Algorithm (GFA) and Multiple Linear Regression Analysis (MLRA) were used to select the descriptors that were used to build the models. The best model built was found to have statistical validation values of squared correlation coefficient (R2) = 0.999, adjusted squared correlation coefficient ( = 0.998, cross validation coefficient = 0.998 and an external squared correlation coefficient = 0.879 which was used to confirm the validation of the model. The docking results showed that ligands 6 and 5 with binding energy (-9.2kcalmol-1 and -9.0kcalmol-1) respectively have the highest binding affinity when compared to the reference drug doxorubicin with binding energy (-6.8kcalmol-1). The stability and robustness of the built model showed that new anti-breast cancer agents can be design from these derivatives.

In order to gain further insights into the structural requirements for anti-tuberculosis activity by chalcone derivatives of 1,3-diphenylprop-2-ene-1-one, quantitative structure activity relationship (QSAR) was performed using genetic function approximation (GFA). Geometry optimization was achieved at the density functional theory (DFT) level using Becke’s three-parameter Lee-Yang-Parr hybrid functional (B3LYP) in combination with the 6-31G* basis set. Subsequently, quantum chemical and molecular descriptors were generated and divided into training and test sets by Kennard Stone algorithm. Internal and external validations as well as Y-randomization tests were employed in model validation. Five predictive models were generated by GFA. The generated models showed that constitutional indices, 2D autocorrelations and radial distribution function (RDF) descriptors were important contributors to anti-tuberculosis activity of 1,3-diphenylprop-2-ene-1-one derivatives. Based on validation results, model 4 was chosen as the best of the five models.

Quantitative structure-activity relationship study was done on 62 compounds with anticonvulsant activity in maximal electroshock-induced seizures test. The molecular structure of the compounds was optimized with parametric semi-empirical PM3 method available in Spartan 14 software. Quantum mechanical descriptors were extracted from the property and output module of the software. Combination of activity based-clustering and genetic function algorithm chemo-metric techniques were used to map molecular descriptors to activity values. A well-validated and robust quantitative structure-activity model was obtained with R2 = 0.947, Q2= 0.924, F = 91.42 and R2pred(test) = 0.881. The descriptor contained in the model suggested an increase in the number of O and N atoms in the molecule augments the activity of the studied compounds. Also, the introduction of electron donating substituents is beneficial to the activity of the studied compounds. Armed with these, information, new hypothetical1H-pyrazole-5-carboxylic acid derivatives were designed using template approach and screened in silico. Compounds with hypothetic anticonvulsant activity better than the template were docked with γ-aminobutyrate-aminotransferase and their binding affinity was found to be comparable and even superior to that of 4-aminohex-5-enoic acid (vigabatrin), a known inhibitor of γ-aminobutyrate-aminotransferase., Moroccan Journal of Chemistry, Vol 6, No 4 (2018)

Objectives: The research aimedto develop a theoretical (QSAR) model forpredicting the activity of 1,2,4-Triazole derivatives as anti-tubercularantagonist.Methods: Genetic function approximation (GFA) was employedon a dataset of 1,2,4-Triazole derivatives to investigate their activities behavior on mycobacterium tuberculosis. This approach ledto selection of the optimum descriptors and to generate the correlation QSARmodel that relate their activitiesvalues against mycobacteriumtuberculosis with the molecular structures of the inhibitors. Results: The builtmodel was validated and was found to have squared correlation coefficient (R2)of 0.9134,adjusted squared correlationcoefficient (Radj) of 0.8753 and Leave one out (LOO) cross validationcoefficient () value of 0.8231. The external validation set used forconfirming the predictive power of the model has R2pred of 0.7482.Conclusion:Reliability, stability and robustness of the model obtained by the validationtest indicate that the model can be used to design and synthesis other1,2,4-Triazole derivatives with improved anti-tubercular activities., Amaç: Araştırma, anti-tüberküler antagonisti olarak1,2,4-Triazol türevlerinin aktivitesini tahmin etmeye yönelik teorik (QSAR) birmodel geliştirmeyi amaçlamıştır.Yöntem: Genetik fonksiyon yaklaşımı (GFA),1,2,4-Triazol türevlerinin Mycobacterium tuberculosis üzerine etkitarzlarını araştırmak amacıyla kullanılmıştır. Bu yaklaşım, optimumtanımlayıcıların seçimine ve Mycobacterium tuberculosis üzerine etkideğerlerini inhibitörlerin moleküler yapılarıyla ilişkilendiren korelasyon QSARmodelinin oluşturulmasına imkân vermiştir.Sonuç: Oluşturulan model doğrulanmış ve korelasyonkatsayısının karesi (R2) 0.9134, düzeltilmiş korelasyon katsayısınınkaresi (Radj) 0.8753 ve tek-çıkışlı (LOO) çapraz doğrulama katsayı () değeri 0.8231 olarak bulunmuştur.Modelin öngörücü gücünü doğrulamak için kullanılan harici doğrulama seti,0.7482 'ye sahiptir.Tartışma: Doğrulama testi ile elde edilen modelin güvenilirliği, kararlılığı vesağlamlığı, modelin, gelişmiş anti-füberküler aktivitesine sahip diğer1,2,4-Triazol türevlerini tasarlamak ve sentezlemek için kullanılabileceğinigöstermektedir.