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Covalent Organic Frameworks (COFs) represents a class of remarkable porous materials composed of organic building blocks that are covalently linked in a periodic manner to form crystalline structures. High surface area, high porosity, tunable pore size, and high stability are their exceptional properties, which make them attractive candidates for various applications in the fields of catalysis, energy storage devices, biomedical applications, gas separation and storage applications. In fact, the great interest shown in COFs gave us a stimulus to review the output of the recent substantial efforts in this area. Meanwhile, the development of portable and sophisticated systems based on these particles is believed to create deeper insights for the scientists to embark on new investigations to pave the way for discovering new fundamental characteristics of COFs, modifications. Furthermore, the effect of modifications/fractionalizations on the performance of COFs will be thoroughly explained and challenging problems are mentioned. Moreover, the paper covers an inclusive collection of referenced recent research articles, providing readers with a comprehensive understanding of the subject matter and an extensive bibliography for further exploration. Through this comprehensive overview, the paper alleviates the noteworthy contributions of COFs in driving innovation and progress in a range of key scientific disciplines. [ABSTRACT FROM AUTHOR]

Three new 1,3,4-oxadiazoles (1–3) have been synthesized. The crystal structure of two of them were solved by single crystal X-ray diffraction analysis and a detailed quantitative analysis of the weak noncovalent interactions have been performed by using DFT calculations. In both compounds, the formation of recurrent H-bonded motifs involving the 1,3,4-oxadiazole is observed. In addition, a variety of CH⋯π interactions are established, involving both aliphatic and aromatic C–H bonds and the π-system of the electron rich tert-butylphenyl ring. QTAIM analysis and NCI plots were used to study the nature and the extent of different intermolecular interactions observed in these structures, which were rationalized using MEP surface plots. [ABSTRACT FROM AUTHOR]

In this study, three new hydrazide-based Schiff bases (1–3) have been synthesized via sonication in good to excellent yields 73–90% and mainly characterized by UV-visible, IR, 1H-NMR and single crystal X-ray diffraction analysis. The crystal structure of compounds 1 and 2 is stabilized by N–H⋯O, C–H⋯O and C–H⋯N hydrogen bonds, as well as C–H⋯π contacts. In addition, weak π⋯π stacking interactions were observed in the structure of 2. A detailed analysis of the intermolecular interactions that stabilize the crystal packing has been performed by using Hirshfeld surface analysis and energy framework calculations were carried out to analyze and visualize the topology of the supramolecular assembly, indicating that the dispersion energy is dominant over the electrostatic one in the most energetic dimers of both compounds. The interaction energies associated with the noncovalent interactions observed in the crystal structures and the interplay between them have been calculated using DFT calculations. Moreover, these intermolecular interactions were also characterized by using both Bader's quantum theory of atoms in molecules (QTAIM) and NCI plots. The synthesized alkoxybenzylidene analogs of benzohydrazide and acetohydrazide were screened in vitro against soybean lipoxygenase and were found to show better activity than the standard indomethacin. Putative binding modes and comparison of binding interactions in the protein–ligand complex were analyzed by molecular docking studies. [ABSTRACT FROM AUTHOR]

The crystal structure of m-methoxy-N′-(m-anisoyl)-N-phenylbenzohydrazide has been determined by means of single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic space group P 21/c with unit cell parameters: a = 8.7338(1), b = 24.5602(3), c = 9.6929(1) Å, β = 113.186(2)°, V = 1911.23(4) Å3, Z = 4. The dihedral angles between the mean plane of the central benzene ring and two terminal aromatic rings are 72.44(4)° and 89.90(4)°, respectively. The two methoxyphenyl rings are orthogonal with a dihedral angle of 89.74(4)°. The crystal packing is stabilized by a combination of N-H…O intermolecular hydrogen bonding and weak intermolecular C-H…O interactions. The X-ray structure was compared with the optimized counterpart calculated by the B3LYP/6-311G basis set and the results showed that the optimized geometry can reproduce the crystal structure parameters well. [ABSTRACT FROM AUTHOR]

A new hydrazide derivative N'-(2,4-dinitrophenyi)-2-fluorobenzohydrazide was synthesized and characterized by NMR and IR spectroscopy. The molecular structure was also studied by X-ray diffraction, and the results of the optimized molecular structure are presented and compared with density functional methods with 631-G basis set. The calculated results show that the optimized geometry can well reproduce the crystal structural parameters, for example, bond lengths and angles show good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The title compound, Methyl 5-Hydroxy-1-Phenyl-1H-Pyrazole-3-Carboxylate (C11H10N2O3), was prepared by a one-pot, two-component reaction of an equimolar mixture of phenyl hydrazine and dimethyl acetylene dicarboxylate (DMAD) at reflux temperature for 2 h in a mixture of toluene and dichloromethane as solvent. C11H10N2O3 was crystallized from an ethanol solution in monoclinic space group P21/c with unit cell dimensions α = 9.5408(16), b = 9.5827(16), c = 11.580(2) Å, ß = 105.838(3)°, V = 1018.5(3) ų, Z = 4. [ABSTRACT FROM AUTHOR]