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Aim: Malaria is among the most devastating and widespread tropical parasitic diseases. To overcome antimalarial drug resistance, new drugs need to be developed. This study is designed to establish the pharmacokinetic profile and toxicity of nine quinine derivatives as potential antimalarial drugs using in silico approaches by SwissADME and pkCSM. Methodology: The structures of investigated compounds were translated into canonical SMILES format and then submitted to SwissADME web tool that gives free access to physicochemical properties, pharmacokinetics, drug-likeness and medicinal chemistry friendliness of compounds, and pkCSM webserver for predicting and optimizing pharmacokinetic and toxicity properties. Results: SwissADME mainly used to predict the physicochemical properties of compounds and their drug-likeness revealed that all quinine derivatives have good bioavailability and satisfied the Lipinski’s rule of five. The pkCSM results on the absorption, distribution, metabolism, excretion and toxicity show  that all investigated compounds have a good pharmacokinetic profile and they are safe since they belong to class 4 of the Globally Harmonized System (300 < Category 4 ≤ 2000 mg/kg/day). Conclusion: Drug-likeness and ADME/T predictions of nine investigated quinine derivatives revealed that they are good candidates to oral drug formulation and thus they can be used in a broader context of overcoming the development of resistance by Plasmodium protozoans against most of the drugs currently used to treat malaria. As future prospects, further studies on bioevaluation of compounds are needed to elucidate their potential pharmacological activities.

Aims: A novel β-coronavirus (2019-nCoV) has become a pandemic affecting hundreds of thousands of people worldwide. Since there is no effective treatment, the need of finding alternative methods which can help to curb this pandemic is urgent. This study aims to review the literature on the virucidal and cytotoxic properties of Aloe vera, one of the most studied plants considered as a nutraceutical in order to propose it as an alternative solution against COVID-19. Methodology: The literature review was based mainly on the COVID-19 resources that have been made freely available to the scientific community but also on the usual databases such as Pubmed and Google scholar. Results: The literature review shows that the plant has antiviral activity on several types of virus (Haemorrhagic Viral Rhobdavirus Septicaemia, Herpes simplex virus type 1, Herpes simplex virus type 2, Varicella-Zoster virus, human immunodeficiency virus, Influenza virus, poliovirus, Cytomegalovirus, Human papillomavirus) including coronavirus SARS-CoV-1. The plant is consumed orally in several forms and is safe. It is possible that  molecules of this plant that have already shown effectiveness on other viruses by some mechanisms such as interaction of virus enzyme, breakdown of the viral envelope etc. could participate in the action of the plant. Also, the presence of minerals such as Zinc, which have shown an effect on SARS-CoV-1, could be involved in the antiviral effect of Aloe vera. Conclusion: Molecular docking of the main molecules of Aloe vera with SARS-CoV-2 protease is in progress and clinical trials are necessary to confirm the activity of Aloe vera on COVID-19.

Computational methods are used to predict the most favorable site of temozolomide towards attack by a water molecule. The energetics of the various complexes are presented as well as their geometries, including perturbations of each subunit caused by the presence of the other. Molecular electrostatic potential and Natural Bond Orbital (NBO) data are used to understand the interactions which conclude the terminal amide group is the preferred attack site where water can act as simultaneous proton donor and acceptor. Other potential proton acceptor N atoms within the aromatic ring structure represent weaker binding sites. Some of the less strongly bound structures include a CH•••O H-bond.

Temozolomide was paired with guanine, 6‐selenoguanine, and 6‐thioguanine, as well as the SH tautomer of the latter. The potential energy surface of each heterodimer was searched for all minima, using Dispersion‐Corrected Density Functional Theory and MP2 methods. Among the dozens of minima, three categories were observed. Stacked geometries place the aromatic systems of the two molecules parallel to one another, while the two systems are roughly perpendicular to one another in a second category. Also found are coplanar structures held together by H‐bonds. Dispersion proves to be a dominating attractive force for the stacked structures, less so for perpendicular, and smallest for the coplanar dimers. Geometries and energetics are relatively insensitive to S and Se substitution, but tautomerization reverses relative stabilities of different geometries.