Characterization, molecular modeling and pharmacology of some 2́-hydroxychalcone derivatives as SARS-CoV-2 inhibitor.

This work presented the microwave assisted synthesis of six new 2́-hydroxychalcones and their characterization based on FTIR, UV-Vis, 1H NMR, and mass spectral analysis. Quantum chemical studies confirmed the structures of prepared chalcones. Antioxidant, in vitro antimicrobial and in silico antiviral studies have been performed to evaluate their biological performance. Results of molecular docking of prepared 2́-hydroxychalcones against SARS-CoV-2 (7BQY) main protease disclosed their inhibition which is comparable to standard, remdesivir and better than hydroxychloroquine (HCQ). ADMET prediction revealed them to be non-carcinogenic and relatively safe.

Titanium (IV) complexes of some tetra-dentate symmetrical bis-Schiff bases of 1,6-hexanediamine: Synthesis, characterization, and in silico prediction of potential inhibitor against coronavirus (SARS-CoV-2).

Symmetrical bis-Schiff bases (LH 2) have been synthesized by the condensation of 1,6-hexanediamine (hn) and carbonyl or dicarbonyl. One of the synthesized Schiff bases has been subjected to the molecular docking for the prediction of their potentiality against coronavirus (SARS-CoV-2). Molecular docking revealed that tested Schiff base possessed high binding affinity with the receptor protein of SARS CoV-2 compared with hydroxychloroquine (HCQ). The ADMET analysis showed that ligand is non-carcinogenic and less toxic than standard HCQ. Schiff bases acting as dibasic tetra-dentate ligands formed titanium (IV) complexes of the type [TiL(H2O)2Cl2] or [TiL(H2O)2]Cl2 being coordinated through ONNO donor atoms. Ligands and complexes were characterized by the elemental analysis and physicochemical and spectroscopic data including FTIR, 1H NMR, mass spectra, UV-Visible spectra, molar conductance, and magnetic measurement. Optimized structures obtained from quantum chemical calculations supported the formation of complexes. Antibacterial, antifungal, and anti-oxidant activity assessments have been studied for synthesized ligands and complexes.

Shear stress tolerance of Streptococcus mutans aggregates determined by microfluidic funnel device (µFFD).

Dental caries are initiated by the attachment of Streptococcus mutans aggregates to the surface of teeth. Bacterial adhesion to the interproximal space, the space between adjacent teeth, has not been investigated due to the lack of devices that mimic the space. Herein, we describe a method for determining the effect of shear stress and sucrose on the attachment of S. mutans aggregates to the interproximal space using microfluidic funnel device (µFFD). Using µFFD, the shear stress tolerance of sucrose-independent and sucrose-dependent S. mutans aggregates (larger than 50 µm in diameter) trapped in the funnel was tested against various flow rates of saliva solution (5 to 50 µl/min). Sucrose-independent aggregates were completely removed from the funnel walls at a low flow rate (10 µl/min) within 7 min., while sucrose-dependent aggregates were removed from the walls only at higher flow rates (25 and 50 µl/min) within several minutes. These results suggest that sucrose-dependent aggregates are more tolerant of shear stress than sucrose-independent aggregates, and are more likely to remain in the region with the smallest shear stress in the teeth.