Crystal structure and Hirshfeld surface analysis of ethyl 2-[5-(3-chloro-benz-yl)-6-oxo-3-phenyl-1,6-di-hydro-pyridazin-1-yl]acetate

Crystal structure and Hirshfeld surface analysis of 4-(2,6-di-chloro-benz-yl)-6-[(E)-2-phenyl-ethen-yl]pyridazin-3(2H)-one

The title pyridazinone derivative, C19H14Cl2N2O, an important pharmacophore with a wide variety of biological applications is not planar, the chloro-phenyl and pyridazinone rings being almost perpendicular, subtending a dihedral angle of 85.73 (11)°. The phenyl ring of the styryl group is coplanar with the pyridazinone ring [1.47 (12)°]. In the crystal, N-H⋯O hydrogen bonds form inversion dimers with an R 2 2(8) ring motif and C-H⋯Cl hydrogen bonds also occur. The roles of the inter-molecular inter-actions in the crystal packing were clarified using Hirshfeld surface analysis, and two-dimensional fingerprint plots indicate that the most important contributions to the crystal packing are from H⋯H (37.9%), C⋯H/H⋯C (18.7%), Cl⋯H/ H⋯Cl (16.4%) and Cl⋯C/C⋯Cl (6.7%) contacts.

Synthesis, spectroscopy, crystal structure, TGA/DTA study, DFT and molecular docking investigations of (E)-4-(4-methylbenzyl)-6-styrylpyridazin-3(2H)-one

In this study, we present the synthesis of novel pyridazin-3(2H)-one derivative namely (E)-4-(4-methylbenzyl)-6-styrylpyridazin-3(2H)-one (MBSP). The chemical structure of MBSP was characterized using spectroscopic techniques such as FT-IR, ¹H NMR, ¹³C NMR, UV-Vis, ESI-MS, and finally, the structure was confirmed by single X-ray diffraction studies. The DFT calculation was performed to compare the gas-phase geometry of the title compound to the solid-phase structure of the title compound. Furthermore, a comparative study between theoretical UV-Vis, IR, ¹H- and ¹³C NMR spectra of the studied compound and experimental ones have been carried out. The thermal behavior and stability of the compound were analyzed by using TGA and DTA techniques which revealed that the compound is thermostable up to its melting point. Finally, the in silico docking and ADME studies are performed to investigate whether MBSP is a potential therapeutic for COVID-19.

Polymorphism of 2-(5-benzyl-6-oxo-3-phenyl-1,6-di-hydro-pyridazin-1-yl)acetic acid with two monoclinic modifications: crystal structures and Hirshfeld surface analyses

Two polymorphs of the title compound, C19H16N2O3, were obtained from ethano-lic (polymorph I) and methano-lic solutions (polymorph II), respectively. Both polymorphs crystallize in the monoclinic system with four formula units per cell and a complete mol-ecule in the asymmetric unit. The main difference between the mol-ecules of (I) and (II) is the reversed position of the hy-droxy group of the carb-oxy-lic function. All other conformational features are found to be similar in the two mol-ecules. The different orientation of the OH group results in different hydrogen-bonding schemes in the crystal structures of (I) and (II). Whereas in (I) inter-molecular O-H⋯O hydrogen bonds with the pyridazinone carbonyl O atom as acceptor generate chains with a C(7) motif extending parallel to the b-axis direction, in the crystal of (II) pairs of inversion-related O-H⋯O hydrogen bonds with an R 2 2(8) ring motif between two carb-oxy-lic functions are found. The inter-molecular inter-actions in both crystal structures were analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

Crystal structure, Hirshfeld surface analysis and DFT studies of 2-[5-(4-methyl-benz-yl)-6-oxo-3-phenyl-1,6-di-hydro-pyridazin-1-yl]acetic acid

In the title compound, the phenyl and pyridazine rings are inclined to each other by 10.55 (12)°, whereas the 4-methyl­benzyl ring is nearly orthogonal to the pyridazine ring with a dihedral angle of 72.97 (10)°.

The title pyridazinone derivative, C₂₀H₁₈N₂O₃, is not planar. The phenyl ring and the pyridazine ring are inclined to each other by 10.55 (12)°, whereas the 4-methyl­benzyl ring is nearly orthogonal to the pyridazine ring, with a dihedral angle of 72.97 (10)°. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with an R₂²(14) ring motif. The dimers are linked by C—H⋯O hydrogen bonds, generating ribbons propagating along the c-axis direction. The inter­molecular inter­actions were additionally investigated using Hirshfeld surface analysis and two-dimensional fingerprint plots. They revealed that the most significant contributions to the crystal packing are from H⋯H (48.4%), H⋯O/O⋯H (21.8%) and H⋯C/C⋯H (20.4%) contacts. Mol­ecular orbital calculations providing electron-density plots of HOMO and LUMO mol­ecular orbitals and mol­ecular electrostatic potentials (MEP) were also computed, both with the DFT/B3LYP/6–311 G++(d,p) basis set.

Crystal structure and Hirshfeld surface analysis of (E)-6-(4-hy-droxy-3-meth-oxy-styr-yl)-4,5-di-hydro-pyridazin-3(2H)-one

In the title com­pound, inter­molecular C—H⋯O, O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional supra­molecular network.

In the title com­pound, C₁₃H₁₄N₂O₃, the dihydropyridazine ring (r.m.s. deviation = 0.166 Å) has a screw-boat conformation. The dihedral angle between its mean plane and the benzene ring is 0.77 (12)°. In the crystal, inter­molecular O—H⋯O hydrogen bonds generate C(5) chains and N—H⋯O hydrogen bonds produce R₂²(8) motifs. These types of inter­actions lead to the formation of layers parallel to (12). The three-dimensional network is achieved by C—H⋯O inter­actions, including R₂⁴(8) motifs. Inter­molecular inter­actions were additionally investigated using Hirshfeld surface analysis and two-dimensional fingerprint plots. The most significant contributions to the crystal packing are by H⋯H (43.3%), H⋯C/C⋯H (19.3%), H⋯O/H⋯O (22.6%), C⋯N/N⋯C (3.0%) and H⋯N/N⋯H (5.8%) contacts. C—H⋯π inter­actions and aromatic π–π stacking inter­actions are not observed.