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A series of hydroquinolines derivatives (2a-2c) have been achieved by a cyclocondensation reaction. The synthesis of 2-oxo −1,2-dihydroquinoline-4-carboxylic acid derivatives (3a-3c) has been carried out using alkylation reactions under phase transfer catalysis (PTC) conditions. The prepared products were characterized through spectroscopic NMR 1H and 13C, IR and single crystal X-ray diffraction techniques. 2D and 3D Hirshfeld surfaces (for 3a and 3b) studies were realized to understand non-bonding intermolecular interactions in solid phase crystal packing of the compound. With the optimized structures, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and clouds were obtained and evaluated. Good agreement was found between the calculated results and experimental data. Furthermore, the molecular docking study is performed to investigate binding patterns of the synthesized molecules (3a and 3b) into 1M17 inhibitor using Auto-Dock Vina program. The antioxidant activity of compounds (3a-3c) has been evaluated using DPPH free radical scavenging, ferric reducing (FRAP) power and β-carotene kinetic blanching assays. Both DPPH and FRAP methods confirmed that 3b had the best antioxidant activity followed by 3c. On the other hand, β-carotene bleaching assay showed the high activity of the product 3a.

A new selective synthesis of novel quinoline carboxamides was developed by the N-alkylation reaction of methyl (2-oxo-1,2- dihydroquinolin-4-yl)-L-alaninate via phase transfer catalysis in a basic medium at room temperature. The compounds were obtained in excellent yields (70-90%) and characterized by H-1, (CNMR)-C-13 spectroscopy and mass spectra. In addition, theoretical studies at B3LYP/6-311G(d,p) level were carried out to explain the observed selectivity of the N-alkylation reaction of compound 2 . The biological activities of the synthesized compounds were studied using some bacterial and fungal strains. The results show that compounds 3h and 3i exhibit stronger antibacterial activity against Bacillus subtilis and Staphyloccocus aureus. Compound 3e showed high antifungal activity against Candida Albicans compared to other substituted quinoline carboxamides. Molecular docking and molecular dynamics studies were also carried out to investigate the binding affinities of some compounds with the target proteins, and the results were in good correlation with the experimental findings. (C) 2021 Elsevier B.V. All rights reserved.

Herein, new 2-oxo-1,2-dihydroquinoline-4-carboxylate derivatives (2a-5d) have been synthesized based on a developed systematic approach, only by esterification reactions of 2-oxo-1,2-dihydroquinoline-4-carboxylic acid with various kinds of alcohols, followed by an alkylation reactions using a different alkylating agents. All the generated compounds are characterized by NMR spectroscopy (1H and 13C). The structures of compounds (2b, 3c, 4a, and 4d) were confirmed using monocrystalline X-ray crystallography. The docking study of the developed derivatives and targets of protein database inhibitors (PDB: 1M17 -EGFR kinase) showed useful information on possible interactions. The experimental results and the expected spectral data using the DFT method at the B3LYP/6-31G(d,p) level of theory were compared. Bi- and three-dimensions Hirshfeld surface examinations have been realized to reveal the non-bond interactions in solid-phase crystal packing and to identify the neighboring inter-molecular contacts for the three molecules 3c, 4a, and 4d. Monte Carlo simulations in the aqueous phase were used to expect the affinity of these derivatives toward mitigation of iron and copper corrosion in acidic and neutral solutions. A proper protection property is anticipated for compounds 3c and 4d.

An efficient synthesis of novel alkyl 2-oxo-1,2-dihydroquinoline-4-carboxylates (3a-3d) was developed, starting from 2-oxo-quinoline carboxylic acid 1a which successively undergoes esterification and alkylation reactions. The structures of all the obtained compounds were investigated and characterized by using 1H NMR and 13C NMR spectroscopic measurements. The molecular and crystal structures of four compounds (3a, 3b, 3c and 3d) have also been examined by single crystal X-ray crystallography. Furthermore, the experimental data and the predicted spectral data were also obtained using density functional theory (DFT) at the B3LYP/6–31G(d,p) level of theory. Also, the closest contacts between the active atoms of the four structures were identified through Hirshfeld surface analyses, molecular docking studies, and DFT calculations. The experimental results are correlated to the calculated ones and showed great compatibility. Finally, molecular docking studies are performed to investigate the binding patterns of the titled compounds with the Protein Data Bank (PDB:1M17-EGFR kinase) inhibitor targets and showed good insights on the possible interactions using the Auto-Dock Vina program.

Sixteen new quinoline derivatives (3e18) have been synthesized through cyclocondensation, nucleophilic substitution and alkylation reactions. All the obtained compounds have been characterized using 1 H-, 13C and 19F NMR spectroscopic measurements. The molecular and crystal structures of four of these compounds (10, 11, 15 and 18) have also been further examined by single crystal X-ray crystallography. The predicted spectral data were also obtained and compared to the experimental results using density functional theory (DFT). in order to understand the non-bonding intermolecular interactions in solid phase crystal packing. The closest contacts between active atoms of the four studied molecules were identified through both 2D and 3D Hirshfeld surface analyses. The different structures of the four compounds are optimized and their both energies highest occupied molecular orbitals (HOMO) and lowest unoccupied molecular orbitals (LUMO), as well as their clouds are evaluated. The obtained experimental results are correlated to the calculated ones and showed great compatibility. Finally, molecular docking studies are performed to investigate the binding patterns of the title compounds with the Protein Data Bank (PDB: 1M17) inhibitor targets and showed good insights on the possible interactions using the Auto-Dock Vina program. Author would like to thank Prof. Jerry P. Jasinski acknowledges the NSF-MRI program (Grant No. CHE-1039027) for funds to purchase the X-ray diffractometer. T. H. is grateful to Hacettepe University Scientific Research Project Unit (Grant No. 013 D04 602 004).