The New Coronavirus (SARS-CoV-2): A Comprehensive Review on Immunity and the Application of Bioinformatics and Molecular Modeling to the Discovery of Potential Anti-SARS-CoV-2 Agents.

On March 11, 2020, the World Health Organization (WHO) officially declared the outbreak caused by the new coronavirus (SARS-CoV-2) a pandemic. The rapid spread of the disease surprised the scientific and medical community. Based on the latest reports, news, and scientific articles published, there is no doubt that the coronavirus has overloaded health systems globally. Practical actions against the recent emergence and rapid expansion of the SARS-CoV-2 require the development and use of tools for discovering new molecular anti-SARS-CoV-2 targets. Thus, this review presents bioinformatics and molecular modeling strategies that aim to assist in the discovery of potential anti-SARS-CoV-2 agents. Besides, we reviewed the relationship between SARS-CoV-2 and innate immunity, since understanding the structures involved in this infection can contribute to the development of new therapeutic targets. Bioinformatics is a technology that assists researchers in coping with diseases by investigating genetic sequencing and seeking structural models of potential molecular targets present in SARS-CoV2. The details provided in this review provide future points of consideration in the field of virology and medical sciences that will contribute to clarifying potential therapeutic targets for anti-SARS-CoV-2 and for understanding the molecular mechanisms responsible for the pathogenesis and virulence of SARS-CoV-2.

Design and Synthesis of New Benzophenone Derivatives with In Vivo Anti-Inflammatory Activity through Dual Inhibition of Edema and Neutrophil Recruitment.

A series of novel benzophenone derivatives containing a thiazole heterocyclic nucleus were designed by molecular hybridization. Molecular docking studies have demonstrated the inhibitory potential of the designed compounds against cyclooxygenase (COX) isoenzymes. These compounds were synthesized, characterized, and evaluated for their anti-inflammatory properties by the croton oil-induced ear edema assay to examine their effect on both prostaglandin (PG) production and neutrophils recruitment. The thiazole derivatives displayed a potent effect in terms of reducing ear edema. The analysis suggested that the presence of 4-phenyl-2-hydrazinothiazole and the absence of C4'-OCH3 on the benzophenone derivative structure are strongly related to the inhibition of PG production. In addition, the derivatives 2e, 3a and 3c concomitantly inhibit PG production and neutrophil recruitment, which may be a mechanism of action better than of common NSAIDs due to their inability to inhibit the neutrophil recruitment. Thus, these compounds can be considered as potential lead compounds toward the development of new anti-inflammatory drugs with an innovating mechanism of action.

Structure-based discovery of thiosemicarbazones as SARS-CoV-2 main protease inhibitors.

Aim: Discovery of novel SARS-CoV-2 main protease (Mpro) inhibitors using a structure-based drug discovery strategy. Materials & methods: Virtual screening employing covalent and noncovalent docking was performed to discover Mpro inhibitors, which were subsequently evaluated in biochemical and cellular assays. Results: 91 virtual hits were selected for biochemical assays, and four were confirmed as reversible inhibitors of SARS CoV-2 Mpro with IC50 values of 0.4-3 µM. They were also shown to inhibit SARS-CoV-1 Mpro and human cathepsin L. Molecular dynamics simulations indicated the stability of the Mpro inhibitor complexes and the interaction of ligands at the subsites. Conclusion: This approach led to the discovery of novel thiosemicarbazones as potent SARS-CoV-2 Mpro inhibitors.

Modulation of the Serotonergic Receptosome in the Treatment of Anxiety and Depression: A Narrative Review of the Experimental Evidence.

Serotonin (5-HT) receptors are found throughout central and peripheral nervous systems, mainly in brain regions involved in the neurobiology of anxiety and depression. 5-HT receptors are currently promising targets for discovering new drugs for treating disorders ranging from migraine to neuropsychiatric upsets, such as anxiety and depression. It is well described in the current literature that the brain expresses seven types of 5-HT receptors comprising eighteen distinct subtypes. In this article, we comprehensively reviewed 5-HT1-7 receptors. Of the eighteen 5-HT receptors known today, thirteen are G protein-coupled receptors (GPCRs) and represent targets for approximately 40% of drugs used in humans. Signaling pathways related to these receptors play a crucial role in neurodevelopment and can be modulated to develop effective therapies to treat anxiety and depression. This review presents the experimental evidence of the modulation of the "serotonergic receptosome" in the treatment of anxiety and depression, as well as demonstrating state-of-the-art research related to phytochemicals and these disorders. In addition, detailed aspects of the pharmacological mechanism of action of all currently known 5-HT receptor families were reviewed. From this review, it will be possible to direct the rational design of drugs towards new therapies that involve signaling via 5-HT receptors.

Antibacterial activity of synthetic 1,3-bis(aryloxy)propan-2-amines against Gram-positive bacteria.

Synthetic 1,3-bis(aryloxy)propan-2-amines have been shown in previous studies to possess several biological activities, such as antifungal and antiprotozoal. In the present study, we describe the antibacterial activity of new synthetic 1,3-bis(aryloxy)propan-2-amines against Gram-positive pathogens (Streptococcus pyogenes, Enterococcus faecalis and Staphylococcus aureus) including Methicillin-resistant S. aureus strains. Our compounds showed minimal inhibitory concentrations (MIC) in the range of 2.5-10 µg/ml (5.99-28.58 µM), against different bacterial strains. The minimal bactericidal concentrations found were similar to MIC, suggesting a bactericidal mechanism of action of these compounds. Furthermore, possible molecular targets were suggested by chemical similarity search followed by docking approaches. Our compounds are similar to known ligands targeting the cell division protein FtsZ, Quinolone resistance protein norA and the Enoyl-[acyl-carrier-protein] reductase FabI. Taken together, our data show that synthetic 1,3-bis(aryloxy)propan-2-amines are active against Gram-positive bacteria, including multidrug-resistant strains and can be a promising lead in the development of new antibacterial compounds for the treatment of these infections.

1,3-Bis(aryloxy)propan-2-ols as potential antileishmanial agents.

We describe herein the synthesis and antileishmanial activity of 1,3-bis(aryloxy)propan-2-ols. Five compounds (2, 3, 13, 17, and 18) exhibited an effective antileishmanial activity against stationary promastigote forms of Leishmania amazonensis (IC50  < 15.0 µm), and an influence of compound lipophilicity on activity was suggested. Most of the compounds were poorly selective, as they showed toxicity toward murine macrophages, except 17 and 18, which presented good selective indexes (SI ≥ 10.0). The five more active compounds (2, 3, 13, 17, and 18) were selected for the treatment of infected macrophages, and all of them were able to reduce the number of internalized parasites by more than 80%, as well as the number of infected macrophages by more than 70% in at least one of the tested concentrations. Altogether, these results demonstrate the potential of these compounds as new hits of antileishmanial agents and open future possibilities for them to be tested in in vivo studies.

Synthesis of novel 2,3,4-trisubstituted-oxazolidine derivatives and in vitro cytotoxic evaluation.

We have previously reported the discovery of cytotoxic and pro-apoptotic hit compound 1,1-dimethylethyl (S)- 2,2-dimethyl-4-[(3-nitrophenoxy)methyl]-3-oxazolidinecarboxylate 1 against leukemia cells. In the present work we describe the synthesis of 25 derivatives of this hit varying the substituent at ring or stereochemistry of the oxazolidine ring and evaluated them against human cancer cells lines. Six compounds exerted significant activity against HL60 promyelocytic leukemia cells with IC50 in low micromolar range (4-18 µM) and three compounds displayed activity against MDA-MB231 breast cancer cells (25-37 µM). In vitro cytotoxicity on normal cells PBMC (human peripheral blood mononuclear cells) was also evaluated. Compounds 7e (p-NO2, S) and 7m (p-COOCH3, S) showed good antiproliferative activity against HL60 (4 and 5 µM) and MDA-MB231 (37 and 25 µM) without affecting lymphocyte proliferation in PBMC, indicating low toxicity to normal cells. Besides, compound 7e induced DNA fragmentation on about 100% of HL60 cells at 50 µM. In this case, it was more potent than 7m and lead 1. This indicated that compound 7e has a great pro-apoptotic potential.