Experimental spectral characterization, Hirshfeld surface analysis, DFT/TD-DFT calculations and docking studies of (2Z,5Z)-5-(4-nitrobenzylidene)-3-N(2-methoxyphenyl)-2-N'(2-methoxyphenylimino) thiazolidin-4-one

Structural, electronic, intermolecular interaction, reactivity, vibrational spectroscopy, charge transfer, Hirshfeld surface analysis, pharmacological and hydropathy plot on 5-Bromo nicotinic acid - Antiviral study (Hepatitis A, B, and C)

The therapeutic properties of 5-Bromonicotinatic acid (5BNA) were studied for antiviral illnesses like Hepatitis A, Hepatitis B and Hepatitis C and the influence of electron-donating and electron-withdrawing properties of functional groups on the nicotinic acid was evaluated and represented in this study using the DFT approach. The molecular parameters were determined for both gases as well as for various solvent phases. The reactive areas in the compound are examined utilising Fukui analysis. The molecular interactions are accomplished by recognising the different types of bonding found in the compound using the AIM, ELF, LOL, RDG and IRI. Solvation investigations were demonstrated to have an influence on molecular orbital energy, ESP, UV-Vis and NLO analyses. Electron-hole, NBO and Hirshfeld investigations are used to investigate the transfer of charges and interactions inside the molecule. The method of vibrational spectroscopy (IR and Raman) is used to differentiate and identify the various types of vibrations displayed by the compound. The hydropathy plots for the proteins 2A4O, 6CWD and 2OC8 associated with Hepatitis A, Hepatitis B and Hepatitis C illustrate the disquiet and attraction of the amino acids towards the water.

Absorption wavelength (TD-DFT) and adsorption of metal chalcogen clusters with methyl nicotinate: Structural, electronic, IRI, SERS, pharmacological and antiviral studies (HIV and omicron)

The DFT B3LYP-LAND2DZ technique is used to examine interactions of Methyl nicotinate with copper selenide and zinc selenide clusters. The existence of reactive sites is determined using ESP maps and Fukui data. The energy variations between HOMO and LUMO are utilised to calculate various energy parameters. The Atoms in Molecules and ELF (Electron Localisation Function) maps are employed to investigate the topology of the molecule. The Interaction Region Indicator is used to determine the existence of non-covalent zones in the molecule. The UV-Vis spectrum using the TD-DFT method and DOS graphs are used to obtain the theoretical determination of electronic transition and properties. Structural analysis of the compound is obtained using theoretical IR spectra. To explore the adsorption of copper selenide and zinc selenide clusters on the Methyl nicotinate, the adsorption energy and theoretical SERS spectra are employed. Furthermore, pharmacological investigations are carried out to confirm the drug's non-toxicity. The compound's antiviral efficacy against HIV and Omicron is demonstrated via protein-ligand docking.

Exploring Structural Mechanism of COVID-19 Treatment with Glutathione as a Potential Peptide Inhibitor to the Main Protease: Molecular Dynamics Simulation and MM/PBSA Free Energy Calculations Study

The 2019-novel coronavirus has unfolded everywhere in the world and obliged a billion human beings in open confinement, whereas many treatments, and vaccines have been proposed towards this pandemic. The main protease (M^pro) is an attractive drug target due to the fact that it is the essential protein for virus invasion. This research tests in silico the effect of five vitamins towards M^pro, by employing molecular docking (MD), molecular dynamics simulation (MDS) with molecular mechanics–Poisson–Boltzmann surface area (MM–PBSA) studies. To achieve this work, we have applied some software’s as Autodock Vina, Discovery Studio Visualizer, APBS, and GROMACS. The inhibitors used were decided entirely on the basis of their importance in the production of red blood cells that prevent anemia, in lymphocyte immune system responses, in the regulation of reactive oxygen species production, such as tocopherol (vitamin E), thiamine (vitamin B1), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), biotin (vitamin B7), and glutathione (GSH). The best inhibitor pose established at the highest repetition ratio (RR) and the minimal affinity energy value (MEV), then the best selected inhibitor was considered to MDS. The results indicate that GSH is the leading inhibitor model among the other tested vitamins in the active site of M^pro with a RR value of 94% and MEV of − 5.5 kcal/mol, its RMSD, RMSF, Rg, and hydrogen bonds show stability with M^pro. Furthermore, thiamine, biotin, and tocopherol are viewed as satisfying inhibitors to M^pro, but pyridoxine was observed as the weakest inhibitor. Based on our result, we could recommend the usage of glutathione and vitamin B family as a supportive strategy for feasible remedy of COVID-19 virus.

Novel 3-chloro-6-nitro-1H-indazole derivatives as promising antileishmanial candidates: synthesis, biological activity, and molecular modelling studies

An efficient pathway was disclosed for the synthesis of 3-chloro-6-nitro-1H-indazole derivatives by 1,3-dipolar cycloaddition on dipolarophile compounds 2 and 3. Faced the problem of separation of two regioisomers, a click chemistry method has allowed us to obtain regioisomers of triazole-1,4 with good yields from 82 to 90% were employed. Also, the antileishmanial biological potency of the compounds was achieved using an MTT assay that reported compound 13 as a promising growth inhibitor of Leishmania major. Molecular docking demonstrated highly stable binding with the Leishmania trypanothione reductase enzyme and produced a network of hydrophobic and hydrophilic interactions. Molecular dynamics simulations were performed for TryR-13 complex to understand its structural and intermolecular affinity stability in a biological environment. The studied complex remained in good equilibrium with a structure deviation of ∼1-3 Å. MM/GBSA binding free energies illustrated the high stability of TryR-13 complex. The studied compounds are promising leads for structural optimisation to enhance the antileishmanial activity.