Phytochemicals of Rhus spp. as Potential Inhibitors of the SARS-CoV-2 Main Protease: Molecular Docking and Drug-Likeness Study.

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) induced by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in China and spread to cover the entire world with an ongoing pandemic. The magnitude of the situation and the fast spread of the new and deadly virus, as well as the lack of specific treatment, led to a focus on research to discover new therapeutic agents. AIM: In this study, we explore the potential inhibitory effects of some active polyphenolic constituents of Rhus spp. (sumac) against the SARS-CoV-2 main protease enzyme (Mpro; 6LU7). METHODS: 26 active polyphenolic compounds of Rhus spp. were studied for their antiviral activity by molecular docking, drug likeness, and synthetic accessibility score (SAS) as inhibitors against the SARS-CoV-2 Mpro. RESULTS: The results show that all tested compounds of sumac provided good interaction with the main active site of SARS-CoV-2 Mpro, with better, lower molecular docking energy (kcal/mol) compared to the well-known drugs chloroquine and favipiravir (Avigan). Only six active polyphenolic compounds of Rhus spp. (sumac), methyl 3,4,5-trihydroxybenzoate, (Z)-1-(2,4-dihydroxyphenyl)-3-(3,4-dihydroxyphenyl)-2-hydroxyprop-2-en-1-one, (Z)-2-(3,4-dihydroxybenzylidene)-6-hydroxybenzofuran-3(2H)-one, 3,5,7-trihydroxy-2-(4-hydroxyphenyl)chroman-4-one, 2-(3,4-dihydroxyphenyl)-3,5-dihydroxy-7-methoxy-4H-chroman-4-one, and 3,7-dihydroxy-2-(4-hydroxyphenyl)chroman-4-one, were proposed by drug likeness, solubility in water, and SAS analysis as potential inhibitors of Mpro that may be used for the treatment of COVID-19. CONCLUSION: Six phenolic compounds of Rhus spp. are proposed for synthesis as potential inhibitors against Mpro and have potential for the treatment of COVID-19. These results encourage further in vitro and in vivo investigations of the proposed ligands and research on the preventive use of Rhus spp. against SARS-CoV-2.

Design, Synthesis, Characterization, QSAR, Docking, Anti-inflammatory and Analgesic Evaluation of Some New Phthalazinediones.

BACKGROUND: phthalazine derivatives were reported to possess anticonvulsant , cardiotonic , antibacterial, analgesic , anti-inflammatory, and anti-microbial activity. In the current study, we applied the QSAR for prediction of newly phthalazinediones incorporating thioamide moiety aiming to reach a more potent anti-inflammatory and Analgesic agent. METHODS: Phthalazinediones 10-15 have been synthesized through condensation of dibenzobarallene 3 with thiosemicarbazides 4-8. One equation was predicted using quantitative structure activity relationship (QSAR) and regression analysis for the anti-inflammatory activity with a regression correlation (R) close to unity. The docking studies were performed to investigate the biological trends of the organic compounds (thiol form) against cyclooxygenas- 2 enzyme, which is a responsible inflammation mediator by using Molgro Virtual Docker (MVD) software. The anti-inflammatory activity and analgesic effect of the thioamides 10-15 were determined by collagen II-adjuvant induced paw edema test in rats. RESULTS: Compounds 10, 11, 12, and 14, exhibited promising anti-inflammatory activity. Furthermore, in the pain scoring, compounds 10, 11 and 12 were found to be more effective than piroxicam and the order of the analgesic effect of the investigated compounds is as followed 14 >12 > 10 > 11 > 15. CONCLUSION: It is clear from the foregoing that the compound 14 is a promising compound if future pharmacological detailed studies. This is consistent with what has been predictable equation 1 in this study.

Rational design, synthesis, pharmacophore modeling, and docking studies for identification of novel potent DNA-PK inhibitors.

Drugs of cancer based upon ionizing radiation or chemotherapeutic treatment may affect breaking of DNA double strand in cell. DNA-PK enzyme has emerged as an attractive target for drug discovery efforts toward DNA repair pathways. Hence, the search for potent and selective DNA-PK inhibitors has particularly considered state-of-the art and several series of inhibitors have been designed. In this article, a novel benchmark DNA-PK database of 43 compounds was built and described. Ligand-based approaches including pharmacophore and QSAR modeling were applied and novel models were introduced and analyzed for predicting activity test for DNA-PK drug candidates. Based upon the modeling results, we gave a report of synthesis of fifteen novel 2-((8-methyl-2-morpholino-4-oxo-4H-benzo[e][1,3]oxazin-7-yl)oxy)acetamide derivatives and in vitro evaluation for DNA-PK inhibitory and antiproliferative activities. These fifteen compounds overall are satisfied with Lipinski's rule of five. The biological testing of target compounds showed five promising active compounds 7c, 7d, 7f, 9e and 9f with micromolar DNA-PK activity range from 0.25 to 5µM. In addition, SAR of the compounds activity was investigated and confirmed that the terminal aryl moiety was found to be quite crucial for DNA-PK activity. Moreover flexible docking simulation was done for the potent compounds into the putative binding site of the 3D homology model of DNA-PK enzyme and the probable interaction model between DNA-PK and the ligands was investigated and interpreted.

Synthesis, structural, optical and anti-rheumatic activity of metal complexes derived from (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) with Ru(III), Pd(II) and Zr(IV).

Three new metal complexes derived from Pd(II), Ru(III) and Zr(IV) with (E)-2-amino-N-(1-(2-aminophenyl)ethylidene)benzohydrazide (2-AAB) have been synthesized. The isolated complexes were characterized by elemental analyses, FT-IR, UV-Vis, ES-MS, (1)H NMR, XRD, thermal analyses (TGA and DTA) and conductance. The morphology and the particle size were determined by transmittance electron microscope (TEM). The results showed that, the ligand coordinates to Pd(II) in the enol form, while it coordinates to Ru(III) and Zr(IV) in the keto form. A square planar geometry is suggested for Pd(II) complex and octahedral geometries are suggested for Ru(III) and Zr(IV) complexes. The optical band gaps of the isolated complexes were measured and indicated the semi-conductivity nature of the complexes. The anti-inflammatory and analgesic activities of the ligand and its complexes showed that, Ru(III) complex has higher effect than the well known drug "meloxicam".

Anti-rheumatic potential of ethyl 2-(2-cyano-3-mercapto-3-(phenylamino) acrylamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate and its Co(II), Cu(II) and Zn(II) complexes.

Ethyl 2-(2-cyano-3-mercapto-3-(phenylamino)acrylamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate [THBTD] and its [Co(THBTD]-H)Ac], [Cu(THBTD]-H)Ac]H2O and [Zn(THBTD)-H)Ac] complexes have been synthesized via the reaction of thiocarbamoyl derivatives with metal ions namely; Co(II), Cu(II) and Zn(II) acetate, respectively. The newly synthesized complexes were characterized by elemental analysis, spectral analysis (UV-Vis, IR, (1)H NMR and EPR), conductance, thermal analysis and magnetic moments. The in vivo collagen-adjuvant arthritis model in rats revealed significant antioxidant, analgesic and anti-rheumatic effects for [THBTD] and its copper complex.

Evaluation of the anti-inflammatory and analgesic effects of Cu(II) and Zn(II) complexes derived from 2-(naphthalen-1-yloxy)-N'-(1-(pyridin-2-1)ethylidene) acetohydrazide.

New Cu(II) and Zn(II) complexes of 2-(naphthalen-1-yloxy)-N'-(1-(pyridin-2-yl)ethylidene) acetohydrazide (HA2PNA) have been prepared and characterized by elemental analyses, spectral (IR, UV-visible, ESR and 1H NMR) as well as magnetic and thermal measurements. According to the data, the complexes assigned the formulae: [Cu(A2PNA)2]H2O and [Zn(A2PNA)(OAc)(H2O)], respectively. IR data revealed that the ligand acts as before ONN and after morever ONN mononegative tridentate via deprotonated carbonyl oxygen (CO) and both (CN)imine and (CN)pyridine nitrogen atoms. The bond lengths, bond angles, HOMO, LUMO, dipole moment and charges on the atoms have been calculated by using density functional theory (DFT) at B3LYP level with 6-31G and 6-31G(d,p) basis sets to confirm the geometry of the ligand and the investigated complexes. Also, the kinetic parameters were determined for each thermal degradation stage of the complexes using Coats-Redfern and Horowitz-Metzger methods. Moreover, the complexes have been tested for anti-inflammatory and analgesic activity in rat model of collagen adjuvant arthritis and compared with piroxicam. All the compounds showed a significant anti-inflammatory and analgesic effect versus piroxicam.