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In this work, the interactions between simple carbon nanotubes (CNTs) and doped carbon nanotubes (DCNTs; with sulfur, boron, aluminum, silicon, phosphorus, or nitrogen) as good adsorbents with various ions such as Fe2 +, Na +, Ca2 +, Mg2 +, Cl−, CO32−, SO42−, and NO3− were fully considered through density functional theory (DFT), natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM) calculations. The adsorption energies (Ead) demonstrated that these ions could be adsorbed on the surface of the CNTs and DCNTs via the exothermic process, especially in the gas phase. QTAIM analysis confirmed that there are non-covalent interactions between these ions and CNT or DCNTs. The calculated energies illustrated that Si-CNTs and B-CNTs have the highest Ead values in the gas and solvent phase, respectively. Moreover, CNTs had the least Ead values in both phases and the best ion with the minimum Ead value in both phases is iron. Finally, population analyses were performed to obtain the reactivity parameters, molecular properties, bonding structural, and density of states (DOS) plots of all structures.

A convenient protocol for amide bond formation for electron deficient amines and carboxylic acids is described. Amide coupling of aniline derivatives has been investigated with a number of reagents under a variety of reaction conditions. The use of 1 equivalent of EDC and 1 equivalent of DMAP, catalytic amount of HOBt and DIPEA provided the best results. This method is amenable to the synthesis of a range of functionalized amide derivatives with electron deficient and unreactive amines.

The COVID‐19 pandemic caused by SARS‐CoV‐2 infection is spreading at an alarming rate and has created an unprecedented health emergency around the globe. There is no effective vaccine or approved drug treatment against COVID‐19 and other pathogenic coronaviruses. The development of antiviral agents is an urgent priority. Biochemical events critical to the coronavirus replication cycle provided a number of attractive targets for drug development. These include, spike protein for binding to host cell‐surface receptors, proteolytic enzymes that are essential for processing polyproteins into mature viruses, and RNA‐dependent RNA polymerase for RNA replication. There has been a lot of ground work for drug discovery and development against these targets. Also, high‐throughput screening efforts have led to the identification of diverse lead structures, including natural product‐derived molecules. This review highlights past and present drug discovery and medicinal‐chemistry approaches against SARS‐CoV, MERS‐CoV and COVID‐19 targets. The review hopes to stimulate further research and will be a useful guide to the development of effective therapies against COVID‐19 and other pathogenic coronaviruses., Effective antiviral treatment? The review highlights potential drug design targets against pathogenic coronaviruses, particularly Covid‐19 as well as past and recent progress towards the development of small‐molecule drug‐like compounds including protein‐X‐ray structure‐based design of cysteine protease inhibitors. Hopefully, the present review will stimulate development of much needed effective drugs against Covid‐19.

The detailed mechanisms for the initial steps of methanol to gasoline (MTG) process, up to 3-carbons products, were studied using DFT calculations and aluminum doped graphene (AG) as catalyst. During the study, the structures of the reactants, products, intermediates and transition states were optimized and confirmed by frequency and IRC calculations. The most of steps are energetically affordable with acceptable barrier energies. The best route (by considering both thermodynamic and kinetic values) was producing ethanol as intermediate and 1-propanol as 3-carbons product. In addition, the production of dimethyl ether and ethylene as intermediates and methyl ethyl ether as a product were energetically possible. This work proved the catalytic ability of AG for MTG process and the results could be employed in the future experimental studies regard to the developments of new catalysts for MTG process.

In this study, noncovalent interactions between Fluoxetine (FX) and different carbon nanotubes (CNTs) or sulfur doped carbon nanotubes (SCNTs) were fully considered using DFT, natural bond orbital (NBO) and molecular docking calculations. Two different CNTs (and SCNTs) with 7,7 and 8,8 chiralities were considered as the adsorbents and the adsorption of FX by these adsorbents were studied in two cases: into the nanotubes and on their surfaces. The results of DFT and NBO calculations proposed that the 8,8 nanotubes are more suitable adsorbents for FX because the energies of their adsorptions are minimum. Population: analyses were also proposed that the adsorption of FX by SCNTs lead to more changes in electronic and sensing properties than the adsorption by CNTs. Moreover, the adsorption energies, obtained from molecular docking calculations (using 94 different models), proposed that the adsorption of FX into (versus out of) the nanotubes, adsorption processes by double-walled or triple-walled (versus single-walled) nanotubes and the adsorption by nanotubes with 8,8 chiralities are the most favorable adsorption processes.

In this study, various xanthene derivatives have prepared efficiently through a simple method using choline chloride/tin(II) chloride (ChCl·2SnCl2) deep eutectic solvent (DES), alone, or in the presence of Fe3O4/ƛ-carrageenan/Zn(II) magnetic bionanocatalyst. In the employed procedure, 2-naphthol derivatives have mixed with aromatic or aliphatic aldehydes and the reactions have been completed in the presence of DES at 90 °C in 1.5 h. In addition, using DES/Fe3O4/ƛ-carrageenan/Zn(II), the reaction time was reduced to 30 min. The employed DES has been recycled four times without important loss of its activity.

In this work, various quinoline derivatives were prepared efficiently through a one-pot, three component synthesis using choline chloride/tin(II) chloride (ChCl·2SnCl2) deep eutectic solvent (DES) as a green catalyst. The procedure is free of using toxic solvents or catalyst and it could be categorized as a green method. In this procedure, aniline derivatives, aromatic aldehydes and enolizable aldehydes were mixed in the presence of DES that plays both roles of solvent and the reaction catalyst. Using this methodology, quinoline derivatives were synthesized simply at 60 °C in 2–3 h with high yields (54–97%). All products were purified by chromatography and recrystallization in ethanol. The employed DES have been recycled 4 time without important loss of its activity.