Synthesis, crystal structure, TD/DFT calculations and Hirshfeld surface analysis of 1-(4-((Benzo)dioxol-5-ylmethyleneamino)phenyl)ethanone oxime

Synthesis of hydrazone-based polyhydroquinoline derivatives - antibacterial activities, α-glucosidase inhibitory capability, and DFT study

In recent years, polyhydroquinolines have gained much attention due to their widespread applications in medicine, agriculture, industry, etc. Here, we synthesized a series of novel hydrazone-based polyhydroquinoline derivatives via multi-step reactions. These molecules were characterized by modern spectroscopic techniques (1H-NMR, 13C NMR, and LC-HRMS) and their antibacterial and in vitro α-glucosidase inhibitory activities were assessed. Compound 8 was found to be the most active inhibitor against Listeria monocytogenes NCTC 5348, Bacillus subtilis IM 622, Brevibacillus brevis, and Bacillus subtilis ATCC 6337 with a zone of inhibition of 15.3 ± 0.01, 13.2 ± 0.2, 13.1 ± 0.1, and 12.6 ± 0.3 mm, respectively. Likewise, compound 8 also exhibited the most potent inhibitory potential for α-glucosidase (IC50 = 5.31 ± 0.25 μM) in vitro, followed by compounds 10 (IC50 = 6.70 ± 0.38 μM), and 12 (IC50 = 6.51 ± 0.37 μM). Furthermore, molecular docking and DFT analysis of these compounds showed good agreement with experimental work and the nonlinear optical properties calculated here indicate that these compounds are good candidates for nonlinear optics.

Synthesis, X-ray crystal structure, IR and Raman spectroscopic analysis, quantum chemical computational and molecular docking studies on hydrazone-pyridine compound: As an insight into the inhibitor capacity of main protease of SARS-CoV2

The characterization and synthesis of 3-chloro-2-{(2E)-2-[1-(4-chlorophenyl)ethylidene]hydrazinyl}pyridine (CCPEHP) was investigated in our study. Mass and UV-visible spectra were recorded in chloroform solvent. The CCPEHP molecule containing pyridine and chlorophenyl rings and hydrazone group crystallized in the triclinic system and P-1 space group. FTRaman and FTIR spectra were performed in the solid state. The optimized geometry of CCPEHP was computed by DFT/B3LYP method with 6-311 G (d, p) and 6-31 G (d, p) levels. The computed vibrational analysis, electronic absorption spectrum, electronic properties, molecular electrostatic potential, natural bond orbitals analysis and other calculated structural parameters were determined by using the DFT/B3LYP/6-31 G (d, p) basis set. The correlation of fundamental modes of the compound and the complete vibrational assignments analysis were studied. The strong and weak contacts were identified by using Hirshfeld surface analysis. The molecular modeling results showed that CCPEHP structure strongly binds to COVID-19 main protease by relative binding affinity of -6.4 kcal/mol.

Crystal structure, spectral investigations, DFT and antimicrobial activity of brucinium benzilate (BBA)

The unreported brucinium benzilate (BBA) crystal and Hirshfeld surface analysis indicated the influence of intramolecular hydrogen bonding network on the crystal structure. Protonation occurs at the tertiary nitrogen as it is the most basic site. The protonated N-H⁺ proton was observed at 7.08 ppm and the benzilate carbon COO^- at 178.41 ppm. Molecular electrostatic potential (MEP) studies showed the electron-rich and electron-deficient sites in the molecule for understanding BBA interaction with an enzyme. Frontier molecular orbital (FMO) studies indicated that BBA molecule is thermodynamically stable and the HOMO-LUMO energy gap was found to be 4.454 eV. The highest interaction has the energy (322.86 kcal/mol) between tertiary ammonium N(LP) and H⁺. Inhibition tests showed that brucinium benzilate inhibits Bacillus cereus and Salmonella typhimurium bacteria. ADMET properties indicated that BBA has drug characteristics in binding plasma protein.

Synthesis, structures, DFT calculations, and catalytic application in the direct arylation of five-membered heteroarenes with aryl bromides of novel palladium-N-heterocyclic carbene PEPPSI-type complexes

A new series of Pd-catalysts was synthesized and fully characterized via spectroscopic methods and the Pd–NHC complexes were evaluated via the direct arylation process.