Synthesis, structure elucidation, Hirshfeld surface analysis, DFT, molecular docking and Monte Carlo simulation of new quinoline-4-carboxylate derivatives

Corrosion Inhibition and Adsorption Properties of N-{2-[2-(5-Methyl-1H-pyrazol-3-yl)acetamido]phenyl}benzamide Monohydrate on C38 Steel in 1 M HCl: Insights from Electrochemical Analysis, DFT, and MD Simulations

The heterocyclic compound N-{2-[2-(5-methyl-1H-pyrazol-3-yl)acetamido]-phenyl}benzamide monohydrate (MPAPB) was synthesized and structurally characterized by using nuclear magnetic resonance (NMR), mass spectrometry, and infrared (IR) spectroscopy. Its corrosion inhibition performance for C38 in 1 M HCl was evaluated by using gravimetric weight loss measurements, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques. MPAPB demonstrated a high inhibition efficiency of 90.2% at a concentration of 1 mM, accompanied by a substantial decrease in the corrosion current density. Electrochemical results revealed that MPAPB acts as a mixed-type inhibitor, reducing both anodic and cathodic reactions, while increasing the charge transfer resistance (R p) and decreasing the double-layer capacitance (C dl), indicative of effective surface adsorption. The adsorption behavior of MPAPB was consistent with that of the Langmuir adsorption isotherm, suggesting a combination of physical and chemical adsorption mechanisms. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations further elucidated the interaction between the MPAPB and the steel surface, highlighting the role of electron-donating heteroatoms and π-electron systems in adsorption. These theoretical findings were in agreement with the experimental results, confirming the formation of a protective layer that inhibits corrosion.

Design and Synthesis of Novel Fluorescent 2-(aryloxy)-3-(4,5-diaryl)-1H-imidazol-2-yl)quinolines: Solvatochromic, DFT, TD-DFT Studies, COX-1 and COX-2 Inhibition and Antioxidant Properties

The present work focuses on the synthesis of novel heterocycles 2-(aryloxy)-3-(4,5-diaryl-1H-imidazol-2-yl)quinolines (6k-v) by an effective condensation reaction. These molecules exhibited fluorescent properties and hence for the proper understanding of their optical behavior and quantum yields, solvatochromic studies have been carried out. Further, frontier molecular orbitals, molecular electrostatic potential (MEP), and geometrical structure optimization have been investigated using the B3LYP/6-311G ++ (d, p) method. The energy gap between the HOMO, LUMO of the optical and energy band gap is determined by DFT and UV-visible spectra for TD-DFT studies are done. The screening of these compounds for in vitro COX-1 and COX-2 inhibition and DPPH free radical scavenging ability assays produced promising results. The binding interactions of these molecules against the COX-2 enzyme (PDB: 5IKR) were validated by docking studies.

Novel diphenyltin(IV) complexes with carboxylato N-functionalized 2-quinolone ligands: Synthesis, characterization and in vitro anticancer studies

Three new diphenyltin(IV) complexes, bis(3-(4-methyl-2-oxoquinolinyl-1(2H)-yl)propanoato)diphenyltin(IV) (1), bis(2-(4-methyl-2-oxoquinolin-1(2H)-yl)ethanoato)diphenyltin(IV) (2), and bis(2-(4-hydroxy-2-oxoquinolin-1(2H)-yl)ethanoato)diphenyltin(IV) (3), were synthesized and characterized by elemental microanalysis, FT-IR spectroscopy, and multinuclear (1H, 13C and 119Sn) NMR spectroscopy. Crystal structure of ligand precursor, 2-(4-methyl-2-oxoquinolinyl-1-(2H)-yl)acetic acid (HL2), has been determined by X-ray diffraction studies. Asymmetric bidentate coordination of the carboxylato ligands and skew trapezoidal structures are assumed for the synthesized complexes. In vitro anticancer activity of the synthesized diphenyltin(IV) complexes was evaluated against three human: MCF-7 (breast adenocarcinoma), A375 (melanoma), HCT116 (colorectal carcinoma), and three mouse tumor cell lines: 4T1 (breast carcinoma), B16 (melanoma), CT26 (colon carcinoma) using MTT and CV assays. The IC50 values fall in the range from 0.1 to 3.7 μM. Flow cytometric analysis and fluorescent microscopy suggest that complex 1 induces caspase-dependent apoptosis followed with strong blockade of cell division in HCT116 cells. Since complex 1 showed ROS/RNS scavenging potential mentioned cytotoxicity was not connected with oxidative stress.