Crystal structure, DFT calculation, Hirshfeld surface analysis and energy framework study of 6-bromo-2-(4-bromo-phen-yl)imidazo[1,2-a]pyridine

Regioselective cyclocondensations with thiobarbituric acid: spirocyclic and azocine products, X-ray characterization, and antioxidant evaluation

Multicomponent cyclocondensations of 5-amino-3-methyl-1-phenyl-1H-pyrazole (AMPZ), thiobarbituric acid, and p-formaldehyde under conventional thermal heating or ultrasonic irradiation were studied. Treatment of the reaction mixture in ethanol in an ultrasonic bath for 3 h produced azocine compound 4b, while the same mixture in ethanol under reflux conditions for 15 h produced spiro compound 4a. This work encompasses intricate experimental details, X-ray diffraction measurements, and multifaceted computational analyses employing methods such as the density functional theory and Hirshfeld surface analysis. Crystallographic investigations revealed the molecular structure of the compound and clarified its interactions involving hydrogen bonds and weak intermolecular forces. This article describes the synthesis and characterization of a novel spirocyclic compound. The study also evaluated the antioxidant potential in vitro using the DPPH and ABTS methods. The results showed that these compounds showed the best free radical scavenging ability, even in very small amounts, and that even at very low concentrations, these compounds showed excellent radical scavenging potential. Surprisingly, these compounds exhibited strong (ABTS+) radical scavenging activities, mainly attributed to the HAT mechanism, indicating their potential as therapeutic agents. Facile multipurpose, three-component selective procedures for new spiroheterocycles have been proposed, presenting intriguing perspectives in the field of medicine, particularly in the field of antioxidants. The geometric values of the computationally optimized structure were calculated using the density functional theory in LC-BLYP/6-31(d), aligned with the X-ray diffraction data, reinforcing the precision of our findings.

Comprehensive analysis of crystal structure, spectroscopic properties, quantum chemical insights, and molecular docking studies of two pyrazolopyridine compounds: potential anticancer agents

In this study, two pyrazolo[3,4-b]pyridine derivatives (4a and 4b) were grown using a slow evaporation solution growth technique and characterized by FT-IR, HRMS, 1H/13C NMR spectroscopy, and X-ray crystallography. The 4a and 4b structures crystallized in monoclinic and triclinic systems with space groups P21/n and P1̄, respectively. Theoretical calculations were performed at the DFT/B3LYP level for the optimized geometries. The results were in excellent agreement with the experimental data (spectroscopic and XRD). This investigation encompasses molecular modeling studies including Hirshfeld surface analysis, energy framework calculations, and frontier molecular orbital analysis. Intermolecular interactions within the crystal structures of the compounds were explored through Hirshfeld surface analysis, which revealed the notable presence of hydrogen bonding and hydrophobic interactions. This insight provides valuable information on the structural stability and potential solubility characteristics of these compounds. The research was extended to docking analysis with eight distinct kinases (BRAF, HER2, CSF1R, MEK2, PDGFRA, JAK, AKT1, and AKT2). The results of this analysis demonstrate that both 4a and 4b interact effectively with the kinase-binding sites through a combination of hydrophobic interactions and hydrogen bonding. Compound 4a had the best affinity for proteins; this is related to the fact that the compound is not rigid and has a small size, allowing it to sit well at any binding site. This study contributes to the advancement of kinase inhibitor research and offers potential avenues for the development of new therapeutic agents for cancer treatment.

Piperonal chalcone derivative incorporating the pyrazolo[3,4-b]pyridine moiety; crystal structure, spectroscopic characterization and quantum chemical investigations

A single crystal of a piperonal chalcone derivative was obtained, fully characterized, and crystallized by a slow evaporation technique. The synthesized compound was characterized by UV-Visible, FT-IR, HRMS, 1H NMR, and 13C NMR spectroscopic studies and X-ray crystallography, revealing that the crystal belongs to a triclinic crystal system with a P1̄ space group, Z = 2. In the present work, we focus on molecular modeling studies such as Hirshfeld surface analysis, energy framework calculations, frontier molecular orbital analysis, natural bond orbital analysis, and NLO properties of a π-conjugate system combining the chalcone and the pyrazole[3,4-b]pyridine scaffolds to describe the in-depth structural analysis thereof. Good agreement was found between the calculated results and experimental data. In addition, Hirshfeld surface analysis of the crystal structure showed that the intermolecular stabilization in the crystal packing comes mainly from H⋯H bond interactions. The chalcone crystal exhibits significant NLO properties suggesting that it could be considered a potential candidate for application in nonlinear optical devices.

Crystal structure of 4-bromo-N-(propyl-carbamo-yl)benzene-sulfonamide

The title compound, C10H13BrN2O3S, 1, contains a sulfonyl urea moiety, which possesses potential therapeutic functions (e.g., anti-diabetic and herbicidal). The geometry of 1 is similar to its closely related analogues, chlorpropamide and tolbutamide. This compound crystallizes in the monoclinic space group C2/c, having one mol-ecule in its asymmetric unit. The crystal structure of 1, recorded at 296 K, shows inter-molecular N-H⋯O and C-H⋯O-type infinite hydrogen-bonded chains involving the sulfonyl urea moiety. Hirshfeld surface analysis and the two-dimensional fingerprint plots confirmed hydrogen bonding as the dominant feature in the crystal packing.

Crystal structure and Hirshfeld surface analysis of 2,2,2-tri-fluoro-1-(7-methyl-imidazo[1,2-a]pyridin-3-yl)ethan-1-one

The bicyclic imidazo[1,2-a]pyridine core in the mol-ecule of the title compound, C10H7F3N2O, is planar within 0.004 (1) Å. In the crystal, the mol-ecules are linked by pairs of C-H⋯N and C-H⋯O hydrogen bonds, forming strips. These strips are connected by the F⋯F contacts into layers, which are further joined by π-π stacking inter-actions. The Hirshfeld surface analysis and fingerprint plots reveal that mol-ecular packing is governed by F⋯H/H⋯F (31.6%), H⋯H (16.8%), C⋯H/H⋯C (13.8%) and O⋯H/H⋯O (8.5%) contacts.

Salt formation, hydrogen-bonding patterns and supramolecular architectures of acridine with salicylic and hippuric acid molecules

The intermolecular interactions and salt formation of acridine with 4-aminosalicylic acid, 5-chlorosalicylic acid and hippuric acid were investigated. The salts obtained were acridin-1-ium 4-aminosalicylate (4-amino-2-hydroxybenzoate), C₁₃H₁₀N⁺·C₇H₆NO₃^- (I), acridin-1-ium 5-chlorosalicylate (5-chloro-2-hydroxybenzoate), C₁₃H₁₀N⁺·C₇H₄ClO₃^- (II), and acridin-1-ium hippurate (2-benzamidoacetate) monohydrate, C₁₃H₁₀N⁺·C₉H₈NO₃^-·H₂O (III). Acridine is involved in strong intermolecular interactions with the hydroxy group of the three acids, enabling it to form supramolecular assemblies. Hirshfeld surfaces, fingerprint plots and enrichment ratios were generated and investigated, and the intermolecular interactions were analyzed, revealing their quantitative contributions in the crystal packing of salts I, II and III. A quantum theory of atoms in molecules (QTAIM) analysis shows the charge-density distribution of the intermolecular interactions. The isosurfaces of the noncovalent interactions were studied, which allows visualization of where the hydrogen-bonding and dispersion interactions contribute within the crystal.