Insight into the Crystal Structures and Potential of Two Newly Synthesized Naproxen-Based Hydrazide Derivatives as Potent COX-2 Inhibitors.

Although nonsteroidal anti-inflammatory drugs (NSAIDs) are medicines that are widely used to relieve pain, reduce inflammation, and bring down high temperature, literature confirmed that they still have harmful side effects. Most of their side effects are in the digestive system due to the carboxylic group. As naproxen is one of the NSAIDs, in this work, we try to mask the carboxylic group in naproxen with a relatively safe functional group. So, herein, we report the synthesis of new naproxen-based hydrazones derivatives, namely, (E)-N'-1-(4-chlorophenyl)ethylidene)-2-(6-methoxynaphthalen-2-yl)propane hydrazide (4a) and (E)-N'-(4-hydroxybenzylidene)-2-(6-methoxynaphthalen-2-yl)propane hydrazide ethanol solvate (4b). The compounds were confirmed by X-ray diffraction studies. Hirshfeld surface analyses and energy frameworks of 4a and 4b have been carried out and blind molecular docking studies of them to the COX-2 enzyme were undertaken to obtain binding affinities for judging whether the compounds could act as anti-inflammatory agents. The compounds interact with the key residues: Arg120, Val349, Leu352, Tyr355, Val523, Ala527, Ser530, and Leu531 of the active enzyme pocket. Molecular dynamics studies predicted that the complexes of 4a and 4b with COX-2 are structurally stable and no major conformational changes were observed. Confirmation of the docking and simulation data was achieved by a binding free energies analysis that indicated the dominance of van der Waals energy. The compounds are drug-like molecules as they obey all prominent drug-like rules and have acceptable pharmacokinetic profiles. To investigate the relationship between their intrinsic electronic properties and their possible similarities to actual drugs, the gas-phase DFT optimizations and NBO analyses were also performed in this study.

Synthesis, crystal structure investigation and computational approach to discover potential hydrazide derivatives as a potent inhibitor of cyclooxygenase-2 enzyme.

This study reports the synthesis of two new hydrazide derivatives, namely, (E)-N'-(4- bromobenzylidene)-2-(4-isobutylphenyl)propanehydrazide (4a) and (E)-N'-benzylidene-2-(4-isobutylphenyl)propanehydrazide (4b), respectively. The compounds were synthesized by the reaction of benzaldehyde with Ibuprofen acid hydrazide. Their structures were confirmed by X-ray crystallography. To try to do a more detailed investigation, computational studies including Hirshfeld surface analyses, energy frameworks, density functional theory (DFT) optimizations, frontier orbital analyses, molecular electrostatic potential analyses, and natural bond orbital analyses of the studied compounds are performed. Moreover, molecular docking and dynamics simulations of complexes of the compounds with the cyclooxygenase-2 (COX-2) enzyme were performed to determine the anti-inflammatory potential of the compounds. These analyses predicted the compounds to show maximum chemical interactions and be dynamically stable during simulation time. Furthermore, estimation of binding free energies confirmed the high binding affinity of the compounds for the COX-2 enzyme.

Crystal structure and Hirshfeld surface analysis of N-[(Z)-(2-hy-droxy-phen-yl)methyl-idene]aniline N-oxide.

The conformation of the title compound, C13H11NO2, is partially determined by a strong, intra-molecular O-H⋯O hydrogen bond. The crystal packing consists of strongly corrugated layers parallel to the ac plane and associated through C-H⋯π(ring) inter-actions. A Hirshfeld surface analysis of the crystal structure indicates that the most significant contributions to the crystal packing are from H⋯H (44.1%), C⋯H/H⋯C (29.4%) and O⋯H/H⋯O (17.3%) contacts.

Crystal structures of 1-(4-chloro-phen-yl)-4-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carb-oxy-lic acid and 4-(4-meth-oxy-phen-yl)-1-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carbo-nitrile.

In the title compounds C23H21ClN2O3 [I, namely 1-(4-chloro-phen-yl)-4-(4-methyl-phen-yl)-3,8-dioxo-1,2,5,6,7,8-hexa-hydro-quine-3-carb-oxy-lic acid] and C24H22N2O3 [II, namely 4-(4-meth-oxy-phen-yl)-1-(4-methyl-phen-yl)-2,5-dioxo-1,2,5,6,7,8-hexa-hydro-quinoline-3-carbo-nitrile], each of the cyclo-hexene and di-hydro-pyridine rings of the 1,2,5,6,7,8-hexa-hydro-quinoline moieties adopts a twisted-boat conformation. The asymmetric units of both compounds I and II consist of two independent mol-ecules (A and B). In II A, three carbon atoms of the cyclo-hexene ring are disordered over two sets of sites in a 0.670 (11):0.330 (11) occupancy ratio. In the crystal of I, mol-ecules are linked through classical N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif and with their mol-ecular planes parallel to the crystallographic (020) plane. Non-classical C-H⋯O hydrogen-bonding inter-actions connect the dimers, resulting in a three-dimensional network. In the crystal of II, mol-ecules are linked by C-H⋯N, C-H⋯O and C-H⋯π inter-actions, forming a three-dimensional network.

Crystal structure and Hirshfeld surface analysis of (3S,3aR,6aS)-3-(1,3-diphenyl-1H-pyrazol-4-yl)-5-(4-meth-oxy-phen-yl)-2-phenyl-3,3a,4,5,6,6a-hexa-hydro-2H-pyrrolo-[3,4-d][1,2]oxazole-4,6-dione.

In the title compound, C33H26N4O4, the two fused five-membered rings and their N-bound aromatic substituents form a pincer-like motif. The relative conformations about the three chiral carbon atoms are established. In the crystal, a combination of C-H⋯O and C-H⋯N hydrogen bonds and C-H⋯π(ring) inter-actions leads to the formation of layers parallel to the bc plane. A Hirshfeld surface analysis indicates that the most significant contributions to the crystal packing are from H⋯H (44.3%), C⋯H/H⋯C (29.8%) and O⋯H/H⋯O (15.0%) contacts.

Crystal structure of (E)-1-(3-benzyl-5-phenyl-1,3-thia-zol-2-yl-idene)-2-[(E)-1,2,3,4-tetra-hydro-naphthalen-1-yl-idene]hydrazin-1-ium bromide.

In the title mol-ecular salt, C26H24N3S+·Br-, the dihedral angles between the thia-zole ring and its attached phenyl and benzoyl rings are 54.81 (7) and 85.51 (7)°, respectively. In the crystal, ion pairs are linked by C-H⋯Br and N-H⋯Br hydrogen bonds and are connected into helical chains extending along the c-axis direction by weak, electrostatic S⋯Br- inter-actions. A Hirshfeld surface analysis was performed, which showed the dominant role of H⋯H contacts (51.3%).

Crystal structures of two hydrazide derivatives of mefenamic acid, 3-(2,3-di-methyl-anilino)-N'-[(E)-(furan-2-yl)methyl-idene]benzohydrazide and N'-[(E)-benzyl-idene]-2-(2,3-di-methyl-anilino)benzo-hydrazide.

The conformation about the central benzene ring in the mol-ecule of (I), C20H19N3O2, is partially determined by an intra-molecular N-H⋯O hydrogen bond. In the crystal, chains parallel to the c axis are generated by inter-molecular N-H⋯O hydrogen bonds with the chains assembled into a three-dimensional network structure by inter-molecular C-H⋯O hydrogen bonds and C-H⋯π(ring) inter-actions. The mol-ecule of (II), C22H21N3O, differs from (I) only in the substituent at the hydrazide N atom where a phenyl-methyl-ene moiety for (II) is present instead of a furan-methyl-ene moiety for (I). Hence, mol-ecules of (I) and (II) show similarities in their mol-ecular and crystal structures. The conformation of the central portion of the mol-ecule of (II) is also therefore partially determined by an intra-molecular N-H⋯O hydrogen bond and inter-molecular N-H⋯O hydrogen bonds form chains parallel to the c axis. Likewise, the chains are connected into a three-dimensional network by C-H⋯O hydrogen bonds and C-H⋯π(ring) inter-actions.

Crystal structure and Hirshfeld surface analysis of ethyl 2-[9-(2-hy-droxy-phen-yl)-3,3,6,6-tetra-methyl-1,8-dioxo-2,3,4,4a,5,6,7,8a,9,9a,10,10a-dodeca-hydro-acridin-10-yl]acetate.

In the title compound, C27H33NO5, a 3,3,6,6-tetra-methyl-tetra-hydro-acridine-1,8-dione ring system carries an ethyl acetate substituent on the acridine N atom and an o-hy-droxy-phenyl ring on the central methine C atom of the di-hydro-pyridine ring. The benzene ring is inclined to the acridine ring system at an angle of 80.45 (7)° and this conformation is stabilized by an intra-molecular O-H⋯O hydrogen bond between the hy-droxy substituent on the benzene ring and one of the carbonyl groups of the acridinedione unit. The ester C=O oxygen atom is disordered over major and minor orientations in a 0.777 (9):0.223 (9) ratio and the terminal -CH3 unit of the ethyl side chain is disordered over two sets of sites in a 0.725 (5): 0.275 (5) ratio. In the crystal, C-H⋯O hydrogen bonds combine to link the mol-ecules into a three-dimensional network. van der Waals H⋯H contacts contribute the most to the Hirshfeld surface (66.9%) followed by O⋯H/H⋯O (22.1%) contacts associated with weak hydrogen bonds.

Crystal structure and Hirshfeld surface analysis of 3-[(1E)-(4-{4-[(E)-(3-hy-droxy-benzyl-idene)amino]-phen-oxy}phenyl-imino)-meth-yl]phenol.

In the crystal, the mol-ecule of the title compound, C26H20N2O3, has crystallographically imposed twofold rotation symmetry. The crystal packing consists of layers parallel to the ab plane formed by O-H⋯N and C-H⋯O hydrogen bonds. Between the layers, C-H⋯π inter-actions are observed.