Design, in silico study, synthesis and evaluation of hybrid pyrazole substituted 1,3,5-triazine derivatives for antimalarial activity.

OBJECTIVES: Malaria is a significant global health challenge, particularly in Africa, Asia, and Latin America, necessitating immediate investigation into innovative and efficacious treatments. This work involves the development of pyrazole substituted 1,3,5-triazine derivatives as antimalarial agent. METHODS: In this study, ten compounds 7(a-j) were synthesized by using nucleophilic substitution reaction, screened for in silico study and their antimalarial activity were evaluated against 3D7 (chloroquine-sensitive) strain of P. falciparum. KEY FINDING: The present work involves the development of hybrid trimethoxy pyrazole 1,3,5-triazine derivatives 7 (a-j). Through in silico analysis, four compounds were identified with favorable binding energy and dock scores. The primary focus of the docking investigations was on the examination of hydrogen bonding and the associated interactions with certain amino acid residues, including Arg A122, Ser A108, Ser A111, Ile A164, Asp A54, and Cys A15. The IC50 values of the four compounds were measured in vitro to assess their antimalarial activity against the chloroquine sensitive 3D7 strain of P. falciparum. The IC50 values varied from 25.02 to 54.82 µg/mL. CONCLUSION: Among the ten derivatives, compound 7J has considerable potential as an antimalarial agent, making it a viable contender for further refinement in the realm of pharmaceutical exploration, with the aim of mitigating the global malaria load.

An in-depth analysis of COVID-19 treatment: Present situation and prospects.

Coronavirus disease 2019 (COVID-19) the most contagious infection caused by the unique type of coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), produced a global pandemic that wreaked havoc on the health-care system, resulting in high morbidity and mortality. Several methods were implemented to tackle the virus, including the repurposing of existing medications and the development of vaccinations. The purpose of this article is to provide a complete summary of the current state and future possibilities for COVID-19 therapies. We describe the many treatment classes, such as antivirals, immunomodulators, and monoclonal antibodies, that have been repurposed or developed to treat COVID-19. We also looked at the clinical evidence for these treatments, including findings from observational studies and randomized-controlled clinical trials, and highlighted the problems and limitations of the available evidence. Furthermore, we reviewed existing clinical trials and prospective COVID-19 therapeutic options, such as novel medication candidates and combination therapies. Finally, we discussed the long-term consequences of COVID-19 and the importance of ongoing research into the development of viable treatments. This review will help physicians, researchers, and policymakers to understand the prevention and mitigation of COVID-19.

Design and development of novel N-(4-aminobenzoyl)- l-glutamic acid conjugated 1,3,5-triazine derivatives as Pf-DHFR inhibitor: An in-silico and in-vitro study.

In the present work, a library of 120 compounds was prepared using various aliphatic and aromatic amines. Finally, 10 compounds were selected through in silico screening carrying 4-aminobenzoyl-l-glutamic acid and 1,3,5-triazine moiety. The docking results of compounds 4d16 and 4d38 revealed higher binding interaction with amino acids Asp54 (-537.96 kcal/mol) and Asp54, Phe116 (-618.22 kcal/mol) against wild (1J3I) and quadruple mutant (1J3K) type of Pf-DHFR inhibitors and were comparable to standard WR99210. These compounds were developed by facile and microwave-assisted synthesis via nucleophilic substitution reaction and characterized by different spectroscopic methods. In vitro antimalarial assay results also suggested that these two compounds were having higher antimalarial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strain out of the ten synthesized compounds with IC50 13.25 µM and 14.72 µM, respectively. These hybrid scaffolds might be useful in the lead discovery of a new class of Pf-DHFR inhibitors.

In silico screening, synthesis, and antimalarial evaluation of PABA substituted 1,3,5-triazine derivatives as Pf-DHFR inhibitors.

OBJECTIVES: Drug resistance in malaria parasites necessitates the development of new antimalarial drugs with unique mechanisms of action. In the present research work, the PABA conjugated 1,3,5-triazine derivatives were designed as an antimalarial agent. METHODS: In this present work, a library of two hundred-seven compounds was prepared in twelve different series such as [4A (1-23), 4B(1-22), 4C(1-21), 4D(1-20), 4E(1-19), 4F(1-18), 4G(1-17), 4H(1-16), 4I(1-15), 4J(1-13), 4K(1-12) and 4L(1-11) ] respectively using different primary and secondary aliphatic and aromatic amines. Ten compounds were ultimately selected through in silico screening. They were synthesized by conventional and microwave-assisted methods followed by in vitro antimalarial evaluations performed in chloroquine-sensitive (3D7) and resistant (DD2) strains of P. falciparum. RESULTS: The docking results showed that compound 4C(11) had good binding interaction with Phe116, Met55 (-464.70 kcal/mol) and Phe116, Ser111 (-432.60 kcal/mol) against wild (1J3I) and quadruple mutant (1J3K) type of Pf-DHFR. Furthermore, in vitro, antimalarial activity results indicated that compound 4C(11) showed potent antimalarial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strain of P. falciparum along with IC50 (14.90 µg mL-1) and (8.30 µg mL-1). CONCLUSION: These PABA-substituted 1,3,5-triazine compounds could be exploited to develop a new class of Pf-DHFR inhibitors as a lead candidate.

Pharmacoinformatics-based identification of transmembrane protease serine-2 inhibitors from Morus Alba as SARS-CoV-2 cell entry inhibitors.

Transmembrane protease serine-2 (TMPRSS2) is a cell-surface protein expressed by epithelial cells of specific tissues including those in the aerodigestive tract. It helps the entry of novel coronavirus (n-CoV) or Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the host cell. Successful inhibition of the TMPRSS2 can be one of the crucial strategies to stop the SARS-CoV-2 infection. In the present study, a set of bioactive molecules from Morus alba Linn. were screened against the TMPRSS2 through two widely used molecular docking engines such as Autodock vina and Glide. Molecules having a higher binding affinity toward the TMPRSS2 compared to Camostat and Ambroxol were considered for in-silico pharmacokinetic analyses. Based on acceptable pharmacokinetic parameters and drug-likeness, finally, five molecules were found to be important for the TMPRSS2 inhibition. A number of bonding interactions in terms of hydrogen bond and hydrophobic interactions were observed between the proposed molecules and ligand-interacting amino acids of the TMPRSS2. The dynamic behavior and stability of best-docked complex between TRMPRSS2 and proposed molecules were assessed through molecular dynamics (MD) simulation. Several parameters from MD simulation have suggested the stability between the protein and ligands. Binding free energy of each molecule calculated through MM-GBSA approach from the MD simulation trajectory suggested strong affection toward the TMPRSS2. Hence, proposed molecules might be crucial chemical components for the TMPRSS2 inhibition.

Implication of in silico studies in the search for novel inhibitors against SARS-CoV-2.

Corona Virus Disease-19 (COVID-19) is a pandemic disease mainly caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It had spread from Wuhan, China, in late 2019 and spread over 222 countries and territories all over the world. Earlier, at the very beginning of COVID-19 infection, there were no approved medicines or vaccines for combating this disease, which adversely affected a lot of individuals worldwide. Although frequent mutation leads to the generation of more deadly variants of SARS-CoV-2, researchers have developed several highly effective vaccines that were approved for emergency use by the World Health Organization (WHO), such as mRNA-1273 by Moderna, BNT162b2 by Pfizer/BioNTech, Ad26.COV2.S by Janssen, AZD1222 by Oxford/AstraZeneca, Covishield by the Serum Institute of India, BBIBP-CorV by Sinopharm, coronaVac by Sinovac, and Covaxin by Bharat Biotech, and the first US Food and Drug Administration-approved antiviral drug Veklury (remdesivir) for the treatment of COVID-19. Several waves of COVID-19 have already occurred worldwide, and good-quality vaccines and medicines should be available for ongoing as well as upcoming waves of the pandemic. Therefore, in silico studies have become an excellent tool for identifying possible ligands that could lead to the development of safer medicines or vaccines. Various phytoconstituents from plants and herbs with antiviral properties are studied further to obtain inhibitors of SARS-CoV-2. In silico screening of various molecular databases like PubChem, ZINC, Asinex Biol-Design Library, and so on has been performed extensively for finding effective ligands against targets. Herein, in silico studies carried out by various researchers are summarized so that one can easily find the best molecule for further in vitro and in vivo studies.

In silico study, synthesis, and evaluation of the antimalarial activity of hybrid dimethoxy pyrazole 1,3,5-triazine derivatives.

Malaria continues to become a major global health problem, particularly in Sub-Saharan Africa, Asia, and Latin America. The widespread emergence of resistance to first-line drugs has further bolstered an urgent need for a new and cost-effective antimalarial(s). Thus, the present study enumerates the synthesis of novel hybrid dimethoxy pyrazole 1,3,5-triazine derivatives 7(a-j) and their in silico results short-listed three compounds with good binding energies and dock scores. Docking analysis shows that hydrogen-bonding predominates and typically involves key residues, such as Asp54, Tyr170, Ile164, and Arg122. The in vitro antimalarial evaluation of three top-ranked compounds (7e, 7g, and 7h) showed half-maximal inhibitory concentration values range from 53.85 to 100 µg/ml against chloroquine-sensitive strain 3D7 of Plasmodium falciparum. Compound 7e may be utilized as a lead for further optimization work in drug discovery due to good antimalarial activity.

Microwave-assisted synthesis of hybrid PABA-1,3,5-triazine derivatives as an antimalarial agent.

The present manuscript deals with the development of novel p-aminobenzoic acid (PABA) associated 1,3,5-triazine derivatives as antimalarial agents. The molecules were developed via microwave-assisted synthesis and structures of compounds were ascertained via numerous analytical and spectroscopic techniques. The synthesized compounds were also subjected to ADMET analysis. In a docking analysis, the title compounds showed high and diverse binding affinities towards wild (-162.45 to -369.38 kcal/mol) and quadruple mutant (-165.36 to -209.47 kcal/mol) Pf-DHFR-TS via interacting with Phe58, Arg59, Ser111, Ile112, Phe116. The in vitro antimalarial activity suggested that compounds 4e, 4b, and 4h showed IC50 ranging from 4.18 to 8.66 µg/ml against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum. Moreover, compounds 4g, 4b, 4e, and 4c showed IC50 ranging from 8.12 to 12.09 µg/ml against chloroquine-resistant (Dd2) strain. In conclusion, our study demonstrated the development of hybrid PABA substituted 1,3,5-triazines as a novel class of Pf-DHFR inhibitor for antimalarial drug discovery.

Acute and sub-chronic toxicity studies of Benincasa hispida (Thunb.) cogniaux fruit extract in rodents.

The objective of the present study was to evaluate the safety of standardized 70% ethanolic extract of Benincasa hispida fruit pulp (HABH) in rodents. Chemical characterization of HABH has been done by GC-MS and dimethylsulfoxonium formyl methylide, l-(+)-ascorbic acid and 2,6-dihexadecanoate were identified as major compounds in the extract. Acute oral toxicity study of HABH was done according to the Organization for Economic Cooperation and Development (OECD) guideline, by 'up and down' method, using the limit test at 2000 mg/kg, body weight in mice and were observed up to 14 days. In sub-chronic oral toxicity study, HABH was administered to Wistar rats at doses of 1000, 200 and 40 mg/kg b. w. per day for 90 days. In acute toxicity study, there was no mortality and no behavioural signs of toxicity at the limit test dose level (2000 mg/kg b. w.). In sub-chronic oral toxicity study, there was no significant difference observed in the consumption of food and water, body weight and relative organ weights. Haematological, serum biochemical and urine analysis revealed the non-adverse effects of prolonged oral consumption of HABH. The histopathologic examination did not show any differences in vital organs. Based on our findings, HABH, at dosage levels up to 1000 mg/kg b. w., is non-toxic and safe for long term oral consumption.

Gastro-protective and Anti-stress Efficacies of Monomethyl Fumarate and a Fumaria indica Extract in Chronically Stressed Rats.

Results of the very first experiments conducted to evaluate therapeutic potentials of a fumarate containing Fumaria indica extract and of fairly low daily oral doses of monomethyl fumarate for prevention of chronic unavoidable foot-shock stress-induced gastric ulcers, and possible involvement of diverse neuro-hormonal and oxidative process in their stress response desensitizing effects are reported and discussed in this article. Preventive effects of 21 daily oral 60, 120, and 240 mg/kg doses of a standardized 50 % methanolic F. indica extract (MFI) and 1.25, 2.50, and 5.00 mg/kg/day of pure monomethyl fumarate (MMF) were compared in rats subjected to one hour daily unavoidable foot-shocks. A pharmaceutically well-standardized Withania somnifera (WS) root extract was used as a reference herbal anti-stress agent in all experiments. Effects of the treatments on stress-induced alterations in body weight, adrenal and spleen weights, gastric ulcer and ulcer index, weight of glandular stomach, protective mucosal glycoprotein content, cellular proliferation, oxidative stress on stomach fundus, and brain tissues of male rats were quantified. Other parameters quantified were plasma corticosterone levels, brain monoamine levels, and expressions of the cytokines TNF-α, IL-10, and IL-1ß in blood and brain of stressed and treated rats. Most but not every observed stress-induced anomalies were suppressed or completely prevented by both MFI and pure MMF treatments in dose-dependent manner. Qualitatively, the observed activity profiles of both of them were similar to those of WS dose tested. These results reveal that both MFI and MMF are potent gastro-protective agents against chronic unavoidable stress-induced ulcers and strongly suggest that they act as regulators or modulators of monoamine, corticosterone, and cytokine homeostasis.

A Review on Synthetic Thiazole Derivatives as an Antimalarial Agent.

BACKGROUND: Thiazole is a widely studied core structure in heterocyclic chemistry and has proven to be a valuable scaffold in medicinal chemistry. The presence of thiazole in both naturally occurring and synthetic pharmacologically active compounds demonstrates the adaptability of these derivatives. METHODS: The current study attempted to review and compile the contributions of numerous researchers over the last 20 years to the medicinal importance of these scaffolds, with a primary focus on antimalarial activity. The review is based on an extensive search of PubMed, Google Scholar, Elsevier, and other renowned journal sites for a thorough literature survey involving various research and review articles. RESULTS: A comprehensive review of the antimalarial activity of the thiazole scaffold revealed potential therapeutic targets in Plasmodium species. Furthermore, the correlation of structure-activity-relationship (SAR) studies from various articles suggests that the thiazole ring has therapeutic potential. CONCLUSION: This article intends to point researchers in the right direction for developing potential thiazole-based compounds as antimalarial agents in the future.

Molecular Targets of Valeric Acid: A Bioactive Natural Product for Endocrine, Metabolic, and Immunological Disorders.

BACKGROUNDS: Postbiotics produced by gut microbiota have exhibited diverse pharmacological activities. Valeric acid, a postbiotic material produced by gut microbiota and some plant species like valerian, has been explored to have diverse pharmacological activities. METHODS: This narrative review aims to summarise the beneficial role of valeric acid for different health conditions along with its underlying mechanism. In order to get ample scientific evidence, various databases like Science Direct, PubMed, Scopus, Google Scholar and Google were exhaustively explored to collect relevant information. Collected data were arranged and analyzed to reach meaningful a conclusion regarding the bioactivity profiling of valeric acid, its mechanism, and future prospects. RESULTS: Valeric acid belongs to short-chain fatty acids (SCFAs) compounds like acetate, propionate, butyrate, pentanoic (valeric) acid, and hexanoic (caproic) acid. Valeric acid has been identified as one of the potent histone deacetylase (HDAC) inhibitors. In different preclinical in -vitro and in-vivo studies, valeric acid has been found to have anti-cancer, anti-diabetic, antihypertensive, anti-inflammatory, and immunomodulatory activity and affects molecular pathways of different diseases like Alzheimer's, Parkinson's, and epilepsy. CONCLUSION: These findings highlight the role of valeric acid as a potential novel therapeutic agent for endocrine, metabolic and immunity-related health conditions, and it must be tested under clinical conditions to develop as a promising drug.

Molecular docking and antimalarial evaluation of hybrid para-aminobenzoic acid 1,3,5 triazine derivatives via inhibition of Pf-DHFR.

In this study, a structurally guided pharmacophore hybridization strategy is used to combine the two key structural scaffolds, para-aminobenzoic acid (PABA), and 1,3,5 triazine in search of new series of antimalarial agents. A combinatorial library of 100 compounds was prepared in five different series as [4A (1-22), 4B (1-21), 4 C (1-20), 4D (1-19) and 4E (1-18)] using different primary and secondary amines, from where 10 compounds were finally screened out through molecular property filter analysis and molecular docking study as promising PABA substituted 1,3,5-triazine scaffold as an antimalarial agent. The docking results showed that compounds 4A12 and 4A20 exhibited good binding interaction with Phe58, IIe164, Ser111, Arg122, Asp54 (-424.19 to -360.34 kcal/mol) and Arg122, Phe116, Ser111, Phe58 (-506.29 to -431.75 kcal/mol) against wild (1J3I) and quadruple mutant (1J3K) type of Pf-DHFR. These compounds were synthesized by conventional as well as microwave-assisted synthesis and characterized by different spectroscopic methods. In-vitro antimalarial activity results indicated that two compounds 4A12 and 4A20 showed promising antimalarial activity against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains of Plasmodium falciparum with IC50 (1.24-4.77 µg mL-1) and (2.11-3.60 µg mL-1). These hybrid PABA substituted 1,3,5-triazine derivatives might be used in the lead discovery towards a new class of Pf-DHFR inhibitors.Communicated by Ramaswamy H. Sarma.

Ebselen: A Review on its Synthesis, Derivatives, Anticancer Efficacy and Utility in Combating SARS-COV-2.

Ebselen is a selenoorganic chiral compound with antioxidant properties comparable to glutathione peroxidase. It is also known as 2-phenyl-1,2-benzisoselenazol-3(2H)-one. In studies examining its numerous pharmacological activities, including antioxidant, anticancer, antiviral, and anti-Alzheimer's, ebselen has demonstrated promising results. This review's primary objective was to emphasize the numerous synthesis pathways of ebselen and their efficacy in fighting cancer. The data were collected from multiple sources, including Scopus, PubMed, Google Scholar, Web of Science, and Publons. The starting reagents for the synthesis of ebselen are 2-aminobenzoic acid and N-phenyl benzamide. It was discovered that ebselen has the ability to initiate apoptosis in malignant cells and prevent the formation of new cancer cells by scavenging free radicals. In addition, ebselen increases tumor cell susceptibility to apoptosis by inhibiting TNF-α mediated NF-jB activation. Ebselen can inhibit both doxorubicin and daunorubicin-induced cardiotoxicity. Allopurinol and ebselen administered orally can be used to suppress renal ototoxicity and nephrotoxicity. Due to excessive administration, diclofenac can induce malignancy of the gastrointestinal tract, which ebselen can effectively suppress. Recent research has demonstrated ebselen to inhibit viral function by binding to cysteine-containing catalytic domains of various viral proteases. It was discovered that ebselen could inhibit the catalytic dyad function of Mpro by forming an irreversible covalent bond between Se and Cys145, thereby altering protease function and inhibiting SARS-CoV-2. Ebselen may also inhibit the activation of endosomal NADPH oxidase of vascular endothelial cells, which is believed to be required for thrombotic complications in COVID-19. In this review, we have included various studies conducted on the anticancer effect of ebselen as well as its inhibition of SARS-CoV-2.

Solasodine Containing Solanum torvum L. Fruit Extract Prevents Chronic Constriction Injury-Induced Neuropathic Pain in Rats: In Silico and In Vivo Evidence of TRPV1 Receptor and Cytokine Inhibition.

This study aimed to assess the efficacy of ethanolic extract of Solanum torvum L. fruit (EESTF) containing solasodine in treating chronic constriction injury (CCI)-induced neuropathic pain in rats. Three-dimensional (3D) simulation studies of solasodine binding were conducted on the TRPV1 receptor, IL-6, and TNF-α structures. For in vivo justification, an assessment of behavioral, biochemical, and histological changes was designed after a CCI-induced neuropathic pain model in rats. On days 7, 14, and 21, CCI significantly increased mechanical, thermal, and cold allodynia while producing a functional deficit. IL-6, TNF-α, TBARS, and MPO levels also increased. SOD levels of catalase and reduced glutathione levels also decreased. Administration of pregabalin (30 mg/kg, oral), solasodine (25 mg/kg, oral), and EESTF (100 and 300 mg/kg, oral) significantly reduced CCI-induced behavioral and biochemical changes (P < 0.05). The protective nature of EESTF was also confirmed by histological analysis. Capsaicin, a TRPV1 receptor agonist, abolished the antinociceptive effects of EESTF when used previously. From the observations of the docking studies, solasodine acted as an antagonist at TRPV1, whereas the docking scores of solasodine against TNF-α and IL-6 were reported to be -11.2 and -6.04 kcal/mol, respectively. The attenuating effect of EESTF might be related to its antagonistic effects on TRPV1, suppression of cytokines, and anti-inflammatory and antioxidant properties.

A Review Of Preclinical Tools To Validate Anti-Diarrheal Agents.

BACKGROUND: Since their inception, preclinical experimental models have played an important role in investigating and characterizing disease pathogenesis. These in vivo, ex vivo, and in vitro preclinical tests also aid in identifying targets, evaluating potential therapeutic drugs, and validating treatment protocols. INTRODUCTION: Diarrhea is a leading cause of mortality and morbidity, particularly among children in developing countries, and it represents a huge health-care challenge on a global scale. Due to its chronic manifestations, alternative anti-diarrheal medications must be tested and developed because of the undesirable side effects of currently existing anti-diarrheal drugs. METHODS: Several online databases, including Science Direct, PubMed, Web of Science, Google Scholar and Scopus, were used in the literature search. The datasets were searched for entries of studies up to May, 2022. RESULTS: The exhaustive literature study provides a large number of in vivo, in vitro and ex vivo models, which have been used for evaluating the mechanism of the anti-diarrheal effect of drugs in chemically-, pathogen-, disease-induced animal models of diarrhea. The advances and challenges of each model were also addressed in this review. CONCLUSION: This review encompasses diverse strategies for screening drugs with anti-diarrheal effects and covers a wide range of pathophysiological and molecular mechanisms linked to diarrhea, with a particular emphasis on the challenges of evaluating and predictively validating these experimental models in preclinical studies. This could also help researchers find a new medicine to treat diabetes more effectively and with fewer adverse effects.

Molecular docking and antimalarial evaluation of novel N-(4-aminobenzoyl)-l-glutamic acid conjugated 1,3,5-triazine derivatives as Pf-DHFR inhibitors.

Malaria has been a source of concern for humans for millennia; therefore in the present study we have utilized in-silico approach to generate diverse anti-malarial hit. Towards this, Molinspiration cheminformatics and Biovia Discovery Studio (DS) 2020 were used to conduct molecular modelling studies on 120 designed compounds. Furthermore, the TOPKAT module was used to evaluate the toxicity of the screened compounds. The CDOCKER docking technology was used to investigate protein-ligand docking against the Pf-DHFR-TS protein (PDB ID: 1J3I and 1J3K). These compounds were synthesized using a conventional and microwave-assisted nucleophilic substitution reaction, and they were characterized using a variety of physicochemical and spectroscopic methods. Among the ten compounds tested, Df3 had the highest antimalarial activity against the chloroquine-resistant (Dd2) strain, with an IC50 value of 9.54 µg mL-1 and further demonstrate, molecular dynamics (MD) simulation studies and estimation of MM-PBSA-based free binding energies of docked complexes with 1J3I and 1J3K were carried out. The discovery of a novel class of Pf-DHFR inhibitors can be accomplished using this hybrid scaffold. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03400-2.

Computational guided identification of potential leads from Acacia pennata (L.) Willd. as inhibitors for cellular entry and viral replication of SARS-CoV-2.

BACKGROUND: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) started in 2019 and is still an on-going pandemic. SARS-CoV-2 uses a human protease called furin to aid in cellular entry and its main protease (Mpro) to achieve viral replication. By targeting these proteins, scientists are trying to identify phytoconstituents of medicinal plants as potential therapeutics for COVID-19. Therefore, our study was aimed to identify promising leads as potential inhibitors of SARS-CoV-2 Mpro and furin using the phytocompounds reported to be isolated from Acacia pennata (L.) Willd. RESULTS: A total of 29 phytocompounds were reported to be isolated from A. pennata. Molecular docking simulation studies revealed 9 phytocompounds as having the top 5 binding affinities towards SARS-CoV-2 Mpro and furin. Among these phytocompounds, quercetin-3-O-α-L-rhamnopyranoside (C_18), kaempferol 3-O-α-L-rhamnopyranosyl-(1 → 4)-ß-D-glucopyranoside (C_4), and isovitexin (C_5) have the highest drug score. However, C_18 and C_4 were not selected for further studies due to bioavailability issues and low synthetic accessibility. Based on binding affinity, molecular properties, drug-likeness, toxicity parameters, ligand interactions, bioavailability, synthetic accessibility, structure-activity relationship, and comparative analysis of our experimental findings with other studies, C_5 was identified as the most promising phytocompound. C_5 interacted with the active site residues of SARS-CoV-2 Mpro (GLU166, ARG188, GLN189) and furin (ASN295, ARG298, HIS364, THR365). Many phytocompounds that interacted with these amino acid residues were reported by other studies as potential inhibitors of SARS-CoV-2 Mpro and furin. The oxygen atom at position 18, the -OH group at position 19, and the 6-C-glucoside were identified as the pharmacophores in isovitexin (also known as apigenin-6-C-glucoside). Other in-silico studies reported apigenin as a potential inhibitor of SARS-CoV-2 Mpro and apigenin-o-7-glucuronide was reported to show stable conformation during MD simulations with SARS-CoV-2 Mpro. CONCLUSION: The present study found isovitexin as the most promising phytocompound to potentially inhibit the cellular entry and viral replication of SARS-CoV-2. We also conclude that compounds having oxygen atom at position 18 (C-ring), -OH group at position 19 (A-ring), and 6-C-glucoside attached to the A-ring at position 3 on a C6-C3-C6 flavonoid scaffold could offer the best alternative to develop new leads against SARS-CoV-2.

An in-silico evaluation of different Saikosaponins for their potency against SARS-CoV-2 using NSP15 and fusion spike glycoprotein as targets.

The Public Health Emergency of International Concern declared the widespread outbreak of SARS-CoV-2 as a global pandemic emergency, which has resulted in 1,773,086 confirmed cases including 111,652 human deaths, as on 13 April 2020, as reported to World Health Organization. As of now, there are no vaccines or antiviral drugs declared to be officially useful against the infection. Saikosaponin is a group of oleanane derivatives reported in Chinese medicinal plants and are described for their anti-viral, anti-tumor, anti-inflammatory, anticonvulsant, antinephritis and hepatoprotective activities. They have also been known to have anti-coronaviral property by interfering the early stage of viral replication including absorption and penetration of the virus. Thus, the present study was undertaken to screen and evaluate the potency of different Saikosaponins against different sets of SARS-CoV-2 binding protein via computational molecular docking simulations. Docking was carried out on a Glide module of Schrodinger Maestro 2018-1 MM Share Version on NSP15 (PDB ID: 6W01) and Prefusion 2019-nCoV spike glycoprotein (PDB ID: 6VSB) from SARS-CoV-2. From the binding energy and interaction studies, the Saikosaponins U and V showed the best affinity towards both the proteins suggesting them to be future research molecule as they mark the desire interaction with NSP15, which is responsible for replication of RNA and also with 2019-nCoV spike glycoprotein which manage the connection with ACE2. [Formula: see text] Communicated by Ramaswamy H. Sarma.

Potential Leads from Liquorice Against SARS-CoV-2 Main Protease using Molecular Docking Simulation Studies.

AIM AND OBJECTIVE: At present, the world is facing a global pandemic threat of SARSCoV- 2 or COVID-19 and to date, there are no clinically approved vaccines or antiviral drugs available for the treatment of coronavirus infections. Studies conducted in China recommended the use of liquorice (Glycyrrhiza species), an integral medicinal herb of traditional Chinese medicine, in the deactivation of COVID-19. Therefore, the present investigation was undertaken to identify the leads from the liquorice plant against COVID-19 using molecular docking simulation studies. MATERIALS AND METHODS: A set of reported bioactive compounds of liquorice were investigated for COVID-19 main protease (Mpro) inhibitory potential. The study was conducted on Autodock vina software using COVID-19 Mpro as a target protein having PDB ID: 6LU7. RESULTS: Out of the total 20 docked compounds, only six compounds showed the best affinity towards the protein target, which included glycyrrhizic acid, isoliquiritin apioside, glyasperin A, liquiritin, 1-methoxyphaseollidin and hedysarimcoumestan B. From the overall observation, glycyrrhizic acid followed by isoliquiritin apioside demonstrated the best affinity towards Mpro representing the binding energy of -8.6 and -7.9 Kcal/mol, respectively. Nevertheless, the other four compounds were also quite comparable with the later one. CONCLUSION: From the present investigation, we conclude that the compounds having oxane ring and chromenone ring substituted with hydroxyl 3-methylbut-2-enyl group could be the best alternative for the development of new leads from liquorice plant against COVID-19.