Novel Fluorescent Benzothiazolyl-Coumarin Hybrids as Anti-SARS-COVID-2 Agents Supported by Molecular Docking Studies: Design, Synthesis, X-ray Crystal Structures, DFT, and TD-DFT/PCM Calculations

Abstract

This study revealed the design and preparation of new 3-(benzo[d]thiazol-2-yl)-2H-chromen-2-one derivatives 9a–h. The structures of the synthesized products were elucidated by their spectroscopic data and X-ray crystallography for compounds 9a and 9d. The prepared new compounds were measured for their fluorescence, and a good result indicated that the emission efficiency was decreased by increasing the electron-withdrawing groups from the unsubstituted compound 9a to the highly substituted derivative 9h (2 Br heavy atoms). On the other hand, the B3LYP/6-311G** theoretical level of theory was used to optimize the quantum mechanical calculations of the geometrical characteristics and energy of the novel compounds 9a–h under study. The electronic transition was investigated using the TD-DFT/PCM B3LYP approach, which uses time-dependent density functional calculations. Moreover, the compounds exhibited nonlinear optical properties (NLO) and a small HOMO–LUMO energy gap, which makes them easy to polarize. Furthermore, the acquired infrared spectra were compared with the expected harmonic vibrations of the substances 9a–h. On the other hand, binding energy analyses of compounds 9a–h with human corona virus nucleocapsid protein Nl63 (PDB ID: 5epw) were predicted using molecular docking and virtual screening tools. The results showed a promising binding and how these potent compounds were inhibiting the COVID-19 virus. Compound 9h was the most active anti-COVID-19 agent among all the synthesized benzothiazolyl-coumarin derivatives, as it forms five bonds. The presence of the two bromine atoms in its structure was responsible for the potent activity.

Annulated Heterocyclic[g]Coumarin Composites: Synthetic Approaches and Bioactive Profiling

“…They began their work using 1,2,3-benzenetriol (1) and used sulfuric acid as a catalyst to accomplish a Pechmann reaction with ethyl 3-oxobutyrate (2) to produce the substituted coumarin molecule (3). Compound (3) was then ether-linked with chloropropanone (4) to form compound (5) under the effect of propanone and K 2 CO 3 . The required compound ( 6) is obtained by cyclizing (5) with sodium hydroxide/isopropanol.…”

“…Compound (3) was then ether-linked with chloropropanone (4) to form compound (5) under the effect of propanone and K 2 CO 3 . The required compound ( 6) is obtained by cyclizing (5) with sodium hydroxide/isopropanol. Lastly, magnesium iodide dealkylates (6) to generate (7), with a yield percentage of 89 %, as illustrated in Scheme 1.…”

“…The development of effective and accessible pharmaceutical molecules to address a wide range of illnesses is a primary focus of medicinal chemistry. Because they are versatile chemical entities with antiproliferative, [1] antiradical, [2] antibacterial, [3] antifungal, [4] antiviral, [5,6] inflammatory suppressant, [7] hepatoprotective, [8] cardioprotective, [9] neuroprotective, [10] antidiabetic, [11] and lipid-lowering [12] properties, coumarin-based compounds have drawn a lot of attention in recent decades. Figure 1 illustrates the structure of coumarin, a dicyclic molecule that is made up of a five-membered lactone ring fused with an arene ring.…”

Solid‐State Organic Fluorophore for Latent Fingerprint Detection and Anti‐Counterfeiting Applications

“…This synthetic protocol was different from the other methods for the same molecule which involved, multicomponent reactions, direct CÀ H cross-coupling reaction, and a two-step process to achieve this product. [28][29][30][31][32] The previous reports involve synthesis at high temperatures, long durations, usage of catalysts such as hetero-poly acids, and two steps. However, the present method involves a single-step reaction which takes place within 0.5 hours, and upon washing the precipitate formed with dilute HCl gives 3-BTC with a high yield of 96.23 % without further requirement of purification.…”

New homoleptic imine derivative of lawsone and its metal complexes: Preparation, characterization, in vitro and in silico biological investigation

“…The Schiff base has triggered the curiosity of bioinorganic chemists being that the fact that the compounds have good coordinating properties and can be prepared with ease. [4][5][6][7][8] Also, coordination compounds based on Schiff bases have profound interaction with DNA and other proteins. The observation on the DNA binding mode with the compounds becomes more important because it leads to the identification of the specific DNA site to which the compound binds.…”