The COVID-19 pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a massive viral disease outbreak of international concerns. The present study is mainly intended to identify the bioactive phytocompounds from traditional antiviral herb Houttuynia cordata Thunb. as potential inhibitors for three main replication proteins of SARS-CoV-2, namely Main protease (Mpro), Papain-Like protease (PLpro) and ADP ribose phosphatase (ADRP) which control the replication process. A total of 177 phytocompounds were characterized from H. cordata using GC–MS/LC–MS and they were docked against three SARS-CoV-2 proteins (receptors), namely Mpro, PLpro and ADRP using Epic, LigPrep and Glide module of Schrödinger suite 2020-3. During docking studies, phytocompounds (ligand) 6-Hydroxyondansetron (A104) have demonstrated strong binding affinity toward receptors Mpro (PDB ID 6LU7) and PLpro (PDB ID 7JRN) with G-score of???7.274 and???5.672, respectively, while Quercitrin (A166) also showed strong binding affinity toward ADRP (PDB ID 6W02) with G-score -6.788. Molecular Dynamics Simulation (MDS) performed using Desmond module of Schrödinger suite 2020–3 has demonstrated better stability in the ligand–receptor complexes A104-6LU7 and A166-6W02 within 100 ns than the A104-7JRN complex. The ADME-Tox study performed using SwissADMEserver for pharmacokinetics of the selected phytocompounds 6-Hydroxyondansetron (A104) and Quercitrin (A166) demonstrated that 6-Hydroxyondansetron passes all the required drug discovery rules which can potentially inhibit Mpro and PLpro of SARS-CoV-2 without causing toxicity while Quercitrin demonstrated less drug-like properties but also demonstrated as potential inhibitor for ADRP. Present findings confer opportunities for 6-Hydroxyondansetron and Quercitrin to be developed as new therapeutic drug against COVID-19.
The forced magnetostriction and magnetization are measured in the easy-plane-type two-sublattice NiCl2 antiferromagnet (AFM) in the case where this AFM passes from the multidomain to a single-domain state. It is shown that, in accordance with the magnetoelastic nature of the multidomain state, the field dependences of the forced magnetostriction and magnetization are interrelated and affected by the transition from the multidomain to the single-domain state. The character of these dependences corresponds to the case where the magnetization and striction are proportional to the number of domains with an energetically favored orientation with respect to the external magnetic field. 相似文献
This work describes a rational approach for addressing the prototropy-related problems in heterocycle-based self-assembling systems by the use of degenerate prototropy. As a proof of principle, the utility of degenerate prototropy is demonstrated herein by developing heterocycle-based AADD-type self-assembling modules that exist as "single set of protameric pair (duplex)" in both solution and solid states. These self-assembling modules are quickly accessible in good yield by reacting 2-amino-5,5-disubstituted-1H-pyrimidine-4,6-diones, available in one step by the condensation of alpha,alpha-dialkyl malonates and free guanidine, with isocyanates. Evidence from NMR spectroscopy, ESI mass spectrometry, and single-crystal X-ray diffraction studies confirmed the formation of molecular duplexes. The effect of electronic repulsion in duplex formation is also investigated. Their ready synthetic accessibility, remarkably high propensity to crystal formation, and the novel property of degenerate prototropy would make these novel self-assembling molecules promising candidates for many proposed applications. 相似文献
Summary A rapid and efficient procedure is described for extraction and determination of aminocaproic acid in horse urine. Urine was
extracted by passing through a bonded silica column (Bond-Elut). The adsorbed drug was washed free of endogenous materials
before being eluted. The extract was then examined by thin-layer chromatography and HPLC. The purity of the extract was determined
by gas chromatography-mass spectrometry. 相似文献
The hunt for a cleaner energy carrier leads us to consider a source that produces no toxic byproducts. One of the targeted alternatives in this approach is hydrogen energy, which, unfortunately, suffers from a lack of efficient storage media. Solid-state hydrogen absorption systems, such as lithium amide (LiNH2) systems, may store up to 6.5 weight percent hydrogen. However, the temperature of hydrogenation and dehydrogenation is too high for practical use. Various molar ratios of LiNH2 with sodium hydride (NaH) and potassium hydride (KH) have been explored in this paper. The temperature of hydrogenation for LiNH2 combined with KH and NaH was found to be substantially lower than the temperature of individual LiNH2. This lower temperature operation of both LiNH2-NaH and LiNH2-KH systems was investigated in depth, and the eutectic melting phenomenon was observed. Systematic thermal studies of this amide-hydride system in different compositions were carried out, which enabled the plotting of a pseudo-binary phase diagram. The occurrence of eutectic interaction increased atomic mobility, which resulted in the kinetic modification followed by an increase in the reactivity of two materials. For these eutectic compositions, i.e., 0.15LiNH2-0.85NaH and 0.25LiNH2-0.75KH, the lowest melting temperature was found to be 307 °C and 235 °C, respectively. Morphological studies were used to investigate and present the detailed mechanism linked with this phenomenon. 相似文献
Two unprecedented mixed BIII/PV complexes of meso‐triaryl 25‐oxasmaragdyrins were synthesized in appreciable yields under mild reaction conditions. These unusual 25‐oxasmaragdyrin complexes containing one or two seven‐membered heterocyclic rings comprised of five different atoms (B, C, N, O, and P) were prepared by reacting B(OH)(Ph)‐smaragdyrin and B(OH)2‐smaragdyrin complexes, respectively, with POCl3 in toluene at reflux temperature. The products were characterized by HRMS and 1D‐ and 2D‐NMR spectroscopy. X‐ray crystallography of one of the mixed BIII/PV smaragdyrin complexes indicated that the macrocycle is significantly distorted and contains a stable seven‐membered heterocyclic ring within the macrocycle. The bands in the absorption and emission spectra were bathochromically shifted with reduced quantum yields and singlet‐state lifetimes relative to the free base, meso‐triaryl 25‐oxasmaragdyrin. The mixed BIII/PV complexes were difficult to oxidize but easier to reduce than the free base. The DFT‐optimized structure of the 25‐oxasmaragdyrin complex with two seven‐membered heterocycles indicated that it was a bicyclic spiro compound with two half‐chair‐like conformers. This was in contrast to the chair‐like conformation of the complex with a single seven‐membered heterocyclic ring. Moreover, incorporation of a second phosphate group in the former case stabilized the bonding geometry and resulted in higher stability, which was reflected in the bathochromic shift of the absorption spectra, more‐positive oxidation potential, and less‐negative reduction potential. 相似文献
Anabolic steroids form one of the important classes of doping agents and their consumption has been found to give benefits to the athletes. Inspite of the fact that they also produce adverse effects and damage several organs and systems, their consumption is continuously increasing in competitive games. The World Anti-Doping Agency and International Olympic Committee have banned the use of anabolic steroids and several other compounds. This article focuses an over view of various chromatographic techniques commonly used for detecting anabolic steroids and their metabolites during last 3 years in human biological fluids to establish the cases of doping. The possibility of electrochemistry- and microchip-based techniques have been considered as possible techniques for future to achieve simple and fast analysis at the site of competitive games as the first tool to detect the cases of doping. 相似文献
Surfactant (SDS)‐mediated cleavage of imines was achieved with acetic anhydride to the corresponding carbonyls (aldehydes and ketones) and acetanilides in water at 25–30°C with very good to excellent yields, thus contributing significantly to the green chemistry concept. 相似文献
Structural Chemistry - Density functional theory (DFT) has been employed to study the structure, stability and reactivity of curcumin and some of its important analogues by computing HOMO-LUMO... 相似文献