Project description:The recently emerged COVID-19 virus caused hundreds of thousands of deaths and instigated a widespread fear, threatening the world's most advanced health security. In 2020, chloroquine derivatives are among the drugs tested against the coronavirus pandemic and showed an apparent efficacy. In the present work, the chloroquine and the chloroquine phosphate molecules have been proposed as potential antiviral for the treatment of COVID-19 diseases combining DFT and molecular docking calculations. Molecular geometries, electronic properties and molecular electrostatic potential were investigated using density functional theory (DFT) at the B3LYP/6-31G* method. As results, we found a good agreement between the theoretical and the experimental geometrical parameters (bond lengths and bond angles). The frontier orbitals analysis has been calculated at the same level of theory to determine the charge transfer within the molecule. In order to perform a better description of the FMOs, the density of states was determined. The molecular electrostatic potential maps were calculated to provide information on the chemical reactivity of molecule and also to describe the intermolecular interactions. All these studies help us a lot in determining the reactivity of the mentioned compounds. Finally, docking calculations were carried out to determine the pharmaceutical activities of the chloroquine derivatives against coronavirus diseases. The choice of these ligands was based on their antiviral activities.
Project description:BACKGROUND:Generalized Anxiety Disorder (GAD) is one of the most common anxiety disorders treated in primary care, yet current therapies have limited efficacy and substantial side effects. PURPOSE:To evaluate long-term chamomile (Matricaria chamomilla L.) use for prevention of GAD symptom relapse. METHODS:Outpatients from primary care practices and local communities with a primary diagnosis of moderate-to-severe GAD were enrolled for this two-phase study at a large US academic medical center. During Phase 1, eligible participants received 12 weeks of open-label therapy with chamomile pharmaceutical grade extract 1500mg (500mg capsule 3 times daily). During Phase 2, treatment responders were randomized to either 26 weeks of continuation chamomile therapy or placebo in a double-blinded, placebo-substitution design. The primary outcome was time to relapse during continuation therapy, analyzed using Cox proportional hazards. Secondary outcomes included the proportion who relapsed, treatment-emergent adverse events, and vital sign changes. This study is registered at ClinicalTrials.gov, identifier NCT01072344. RESULTS:Between March 1, 2010, and June 30, 2015, we enrolled 179 participants. Of those, 93 (51.9%) were responders and agreed to continue in the double-blind randomized controlled trial. A numerically greater number of placebo-switched (n=12/47; 25.5%) versus chamomile-continuation (n?=?7/46; 15.2%) participants relapsed during follow-up. Mean time to relapse was 11.4?±?8.4 weeks for chamomile and 6.3?±?3.9 weeks for placebo. Hazard of relapse was non-significantly lower for chamomile (hazard ratio, 0.52; 95% CI, 0.20-1.33; P?=?0.16). During follow-up, chamomile participants maintained significantly lower GAD symptoms than placebo (P?=?0.0032), with significant reductions in body weight (P?=?0.046) and mean arterial blood pressure (P?=?0.0063). Both treatments had similar low adverse event rates. CONCLUSIONS:Long-term chamomile was safe and significantly reduced moderate-to-severe GAD symptoms, but did not significantly reduce rate of relapse. Our limited sample size and lower than expected rate of placebo group relapse likely contributed to the non-significant primary outcome finding. Possible chamomile superiority over placebo requires further examination in large-scale studies.
Project description:Covid-19 is a beta-coronavirus that was first identified during the Wuhan COVID-19 epidemic in 2019. This study is focused on the quantum descriptors of the proposed antiviral drugs, molecular docking, and dynamics simulation with the main protease of coronavirus. Such drugs are Baloxavir, Chloroquine, Avigan, Plaquenil, oseltamivir, Remdesivir, Arbidol, and Sofosbuvir were used for comparison. Density functional theory (DFT) may help find the relevancy of quantum chemical descriptors to explain the potential antiviral activity, Some quantum descriptors such as ΔE; the energy gap, η; global hardness, S; global softness, I: ionization potential, A: electron affinity, χ: absolute electronegativity, ω; ΔE Back-donation; the back donation were calculated based on EHOMO; energy of the highest occupied molecular orbital, and ELUMO; energy of the lowest unoccupied molecular orbital. Fukui indices (f+, f−); for local nucleophilic and electrophilic attacks are investigated for the investigated antiviral drugs. The reported genomic sequence of Covid-19 main protease in complex with an inhibitor N3 (DOI: https://doi.org//10.2210/pdb6LU7/pdb) was used as a precursor for docking with the selected drugs after removing the attached inhibitors N3 and water. Molecular docking was performed using Autodock 4.2, with the Lamarckian Genetic Algorithm, and was analyzed by Autodock 1.5.6 and Pymol version 1.7.4.5 Edu, However, further research is necessary to investigate their potential medicinal use.
Project description:Phytochemical investigations of Matricaria chamomilla L. (Asteraceae) stated the presence of several compounds with an established therapeutic and antioxidant potential. The chamomile non-enzymatic antioxidant system includes low molecular mass compounds, mainly polyphenols such as cinnamic, hydroxybenzoic and chlorogenic acids, flavonoids and coumarins. The objective of this work was to evaluate the role of the non-enzymatic antioxidant system after stimulation by ethylene in tetraploid chamomile plants. Seven days of ethylene treatment significantly increased the activity of phenylalanine ammonia-lyase, which influenced the biosynthesis of protective polyphenols in the first step of their biosynthetic pathway. Subsequently, considerable enhanced levels of phenolic metabolites with a substantial antioxidant effect (syringic, vanillic and caffeic acid, 1,5-dicaffeoylquinic acid, quercetin, luteolin, daphnin, and herniarin) were determined by HPLC-DAD-MS. The minimal information on the chlorogenic acids function in chamomile led to the isolation and identification of 5-O-feruloylquinic acid. It is accumulated during normal conditions, but after the excessive effect of abiotic stress, its level significantly decreases and levels of other caffeoylquinic acids enhance. Our results suggest that ethephon may act as a stimulant of the production of pharmaceutically important non-enzymatic antioxidants in chamomile leaves and thus, lead to an overall change in phytochemical content and therapeutic effects of chamomile plants, as well.
Project description:Currently, there is not any specific effective antiviral treatment for COVID-19. Although most of the COVID-19 patients have mild or moderate courses, up to 5%–10% can have severe, potentially life threatening course, there is an urgent need for effective drugs. Optimized supportive care remains the mainstay of therapy. There have been more than 300 clinical trials going on, various antiviral and immunomodulating agents are in various stages of evaluation for COVID-19 in those trials and some of them will be published in the next couple of months. Despite the urgent need to find an effective antiviral treatment for COVID-19 through randomized controlled studies, certain agents are being used all over the world based on either in-vitro or extrapolated evidence or observational studies. The most frequently used agents both in Turkey and all over the world including chloroquine, hydroxychloroquine, lopinavir/ritonavir, favipiravir and remdesivir will be reviewed here .Nitazoxanide and ivermectin were also included in this review as they have recently been reported to have an activity against SARS-CoV-2 in vitro and are licensed for the treatment of some other human infections.
Project description:The novel coronavirus, COVID-19, caused by SARS-CoV-2, is a global health pandemic that started in December 2019. The effective drug target among coronaviruses is the main protease Mpro, because of its essential role in processing the polyproteins that are translated from the viral RNA. In this study, the bioactivity of some selected heterocyclic drugs named Favipiravir (1), Amodiaquine (2), 2'-Fluoro-2'-deoxycytidine (3), and Ribavirin (4) was evaluated as inhibitors and nucleotide analogues for COVID-19 using computational modeling strategies. The density functional theory (DFT) calculations were performed to estimate the thermal parameters, dipole moment, polarizability, and molecular electrostatic potential of the present drugs; additionally, Mulliken atomic charges of the drugs as well as the chemical reactivity descriptors were investigated. The nominated drugs were docked on SARS-CoV-2 main protease (PDB: 6LU7) to evaluate the binding affinity of these drugs. Besides, the computations data of DFT the docking simulation studies was predicted that the Amodiaquine (2) has the least binding energy (-7.77 Kcal/mol) and might serve as a good inhibitor to SARS-CoV-2 comparable with the approved medicines, hydroxychloroquine, and remdesivir which have binding affinity -6.06 and -4.96 Kcal/mol, respectively. The high binding affinity of 2 was attributed to the presence of three hydrogen bonds along with different hydrophobic interactions between the drug and the critical amino acids residues of the receptor. Finally, the estimated molecular electrostatic potential results by DFT were used to illustrate the molecular docking findings. The DFT calculations showed that drug 2 has the highest of lying HOMO, electrophilicity index, basicity, and dipole moment. All these parameters could share with different extent to significantly affect the binding affinity of these drugs with the active protein sites.
Project description:AbstractThe unavailability of a proper drug against SARS-CoV-2 infections and the emergence of various variants created a global crisis. In the present work, we have studied the antiviral behavior of feverfew plant in treating COVID-19. We have reported a systematic in silico study with the antiviral effects of various phytoconstituents Borneol (C10H18O), Camphene (C10H16), Camphor (C10H16O), Alpha-thujene (C10H16), Eugenol (C10H14O), Carvacrol (C10H14O) and Parthenolide (C15H20O3) of feverfew on the viral protein of SARS-CoV-2. Parthenolide shows the best binding affinity with both main protease (Mpro) and papain-like protease (PLpro). The molecular electrostatic potential and Mulliken atomic charges of the Parthenolide molecule shows the high chemical reactivity of the molecule. The docking of Parthenolide with PLpro give score of -8.0 kcal/mol that validates the good binding of Parthenolide molecule with PLpro. This complex was further considered for molecular dynamics simulations. The binding energy of the complex seems to range in between -3.85 to -11.07 kcal/mol that is high enough to validate the stability of the complex. Free energy decomposition analysis have been also performed to understand the contribution of residues that reside into the binding site. Good binding affinity and reactivity response suggested that Parthenolide can be used as a promising drug against the COVID-19.Graphical abstractSupplementary informationThe online version contains supplementary material available at 10.1007/s11696-022-02067-6.
Project description:In 2020, the world tried to combat the corona virus (COVID-19) pandemic. A proven treatment method specific to Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is still not found. In this study, seven new antiviral compounds were designed for COVID-19 treatment. The ability of these compounds to inhibit COVID-19's RNA processing was calculated by the molecular docking study. It has been observed that the compounds can have high binding affinities especially against NSP12 (between -9.06 and -8.00 kcal/mol). The molecular dynamics simulation of NSP12-ZG 7 complex proved the stability of interaction. The synthesis of two most active molecules was performed by one-pot reaction and characterized by FT-IR, 1H-NMR, 13C-NMR, and mass spectroscopy. The compounds presented with their synthesis are inhibitory core structures against SARS-CoV-2 infection.