Synthesis, crystal structure and Hirshfeld surface analysis of 1-[3-(2-oxo-3-phenyl-1,2-di-hydro-quinoxalin-1-yl)prop-yl]-3-phenyl-1,2-di-hydro-quinoxalin-2-one.

In the title compound, C31H24N4O2, the di-hydro-quinoxaline units are both essentially planar with the dihedral angle between their mean planes being 64.82 (4)°. The attached phenyl rings differ significantly in their rotational orientations with respect to the di-hydro-quinoxaline planes. In the crystal, one set of C-H⋯O hydrogen bonds form chains along the b-axis direction, which are connected in pairs by a second set of C-H⋯O hydrogen bonds. Two sets of π-stacking inter-actions and C-H⋯π(ring) inter-actions join the double chains into the final three-dimensional structure.

Synthesis, crystal structure and Hirshfeld surface analysis of 2-phenyl-3-(prop-2-yn-1-yl-oxy)quin-oxaline.

In the title compound, C17H12N2O, the quinoxaline moiety shows deviations of 0.0288 (7) to -0.0370 (7) Šfrom the mean plane (r.m.s. deviation of fitted atoms = 0.0223 Å). In the crystal, corrugated layers two mol-ecules thick are formed by C-H⋯N hydrogen bonds and π-stacking inter-actions.

Crystal structure and Hirshfeld surface analysis of 3-phenyl-1-{3-[(3-phenyl-quinoxalin-2-yl)-oxy]prop-yl}-1,2-di-hydro-quinoxalin-2-one.

In the title compound, C31H24N4O2, the quinoxaline units are distinctly non-planar and twisted end-to-end. In the crystal, C-H⋯O and C-H⋯N hydrogen bonds link the mol-ecules into chains extending along the a-axis direction. The chains are linked through π-stacking inter-actions between inversion-related quinoxaline moieties.

Synthesis, crystal structure, DFT, Hirshfeld surface analysis, energy frameworks and in-Silico drug-targeting PFKFB3 kinase of novel triazolequinoxalin derivative (TZQ) as a therapeutic Strategy against cancer.

Overall, drug design is a dynamic and evolving field, with researchers constantly working to improve their understanding of molecular interactions, develop new computational methods, and explore innovative techniques for creating effective and safe medications. The process can involve steps such as the identification of targets, the discovery of lead compounds, lead optimization, preliminary testing, human trials, regulatory approval and finally post-marketing surveillance, all aimed at bringing a new drug from concept to market. In this article, the synthesis of the novel triazolequinoxalin (TZQ) 1-((1-hexyl-1H-1,2,3-triazol-5-yl)methyl)-3-phenylquinoxalin-2(1H)-one (4) is reported. The structure has been identified with a variety of spectroscopic methods (1H, 13C NMR, and LC-MS) and finally, the structure has been determined by X-ray diffraction (XRD) studies. The TZQ molecule has crystallized in the monoclinic space C2/c group with unit cell dimensions a = 41.201(2) Å, b = 10.6339(6) Å, c = 9.4997(4) Å, ß = 93.904(4). The crystal structure is stabilized by intermolecular interactions (N-H ⋯ O and N-H … Cg) occurring within the molecule. The presence of these intermolecular interactions is evaluated through analysis of Hirshfeld surfaces (HS) and two-dimensional (2D) chemical fingerprints map. Additionally, energy frameworks were employed to identify the prevailing interaction energy influencing the molecular arrangement. Density Functional Theory (DFT) calculations were computed to establish concurrence between theoretical and experimental results. Furthermore, the HOMO-LUMO energy levels were determined using the B3LYP/6-31+G(d, p) level of theory. Finally, molecular docking was used to predict the anti-cancer activity of the compound (4) against PFKFB3 kinase and presented noticeable hydrophilic and hydrophobic interactions at the active site region.

Crystal structure of ethyl 2-{4-[(2-oxo-3-phenyl-1,2-di-hydro-quinoxalin-1-yl)meth-yl]-1H-1,2,3-triazol-1-yl}acetate.

The quinoxaline portion of the title mol-ecule, C21H19N5O3, is not quite planar as indicated by a dihedral angle of 3.38 (7)° between the constituent rings. The mol-ecule is 'U-shaped', which is consolidated by an intra-molecular anti-parallel carbonyl electrostatic inter-action with C··O distances of 2.8905 (16) and 3.0221 (15) Å, in the crystal forms corrugated layers through C-H⋯O and C-H⋯N hydrogen bonds and C-H⋯π(ring) and π-stacking inter-actions.

Insights into the crystal structure of two newly synthesized quinoxalines derivatives as potent inhibitor for c-Jun N-terminal kinases.

Two new compounds namely, ethyl (2E)-3-(dimethylamino)-2-(3-methoxyquinoxalin-2-yl)propen-2-enoate (II) and ethyl 2-(3-oxo-4-(prop-2-yn-1-yl)-3,4-dihydroquinoxalin-2-yl)-3-phenylpropanoate (III) have been synthesized from ethyl 2-(oxo-3,4-dihydroquinoxalin-2-yl) acetate (I). The compounds were characterized using NMR (1H and 13C), Fourier transform infrared and confirmed by single crystal X-ray diffraction studies. The quinoxaline portion of II is almost planar with the substituent containing the dimethylamino and carboxyethyl groups rotated well out of its mean plane. In the crystal, C-H···O and C-H···N hydrogen bonds as well as C-H···π(ring) interactions form chains having a U-shaped cross-section and running along the c-axis direction. Two sets of pair-wise C-H···O hydrogen bonds connect the chains into corrugated sheets. In III, the three substituents on the dihydroquinoxaline moiety are rotated well out of its mean plane. Three sets of C-H···O hydrogen bonds as well as C-H···π(ring) and π-π-stacking interactions form layers approximately parallel to [001]. These are associated along the c-axis direction by additional C-H···π(ring) interactions. Additionally, the Hirshfeld surface analyses showed that the H···H contact is the most important interaction for both II and III. In addition to this, molecular docking and dynamics studies were carried for these two compounds with the c-Jun N-terminal kinases (JNK1) molecule.Communicated by Ramaswamy H. Sarma.

Crystal structure, Hirshfeld surface analysis and density functional theory study of 1-nonyl-3-phenyl-quinoxalin-2-one.

In the title mol-ecule, C23H28N2O, the phenyl ring is inclined to the quinoxaline ring system at a dihedral angle of 20.40 (9)°. In the crystal, C-H⋯O inter-actions between neighbouring mol-ecules form chains along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (70.6%), H⋯C/C⋯H (15.5%) and H⋯O/O⋯H (4.6%) inter-actions. The optimized structure calculated using density functional theory at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated highest occupied mol-ecular orbital (HOMO) and lowest unoccupied mol-ecular orbital (LUMO) energy gap is 3.8904 eV. Part of the n-nonyl chain attached to one of the nitro-gen atoms of the quinoxaline ring system shows disorder and was refined with a double conformation with occupancies of 0.604 (11) and 0.396 (11).

Crystal structure, Hirshfeld surface analysis and DFT study of N-(2-amino-5-methyl-phen-yl)-2-(5-methyl-1H-pyrazol-3-yl)acetamide.

The title mol-ecule, C13H16N4O, adopts an angular conformation. In the crystal a layer structure is generated by N-H⋯O and N-H⋯N hydrogen bonds together with C-H⋯π(ring) inter-actions. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (53.8%), H⋯C/C⋯H (21.7%), H⋯N/N⋯H (13.6%), and H⋯O/O⋯H (10.8%) inter-actions. The optimized structure calculated using density functional theory (DFT) at the B3LYP/ 6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated HOMO-LUMO energy gap is 5.0452 eV.

Crystal structure and Hirshfeld surface analysis of 2-(2-oxo-3-phenyl-1,2,3,8a-tetra-hydro-quinoxalin-1-yl)ethyl acetate.

In the title mol-ecule, C18H16N2O3, the di-hydro-quinoxaline moiety, with the exception of the N atom is essentially planar with the inner part of the methyl-propano-ate group (CH2-CH2-O) nearly perpendicular to it. In the crystal, inversion dimers formed by C-H⋯O hydrogen bonds are connected into oblique stacks by π-stacking and C-H⋯π(ring) inter-actions.

Crystal structure, Hirshfeld surface analysis and density functional theory study of 6-methyl-2-[(5-methyl-isoxazol-3-yl)meth-yl]-1H-benzimidazole.

In the title mol-ecule, C13H13N3O, the isoxazole ring is inclined to the benzimidazole ring at a dihedral angle of 69.28 (14)°. In the crystal, N-H⋯N hydrogen bonds between neighboring benzimidazole rings form chains along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (48.8%), H⋯C/C⋯H (20.9%) and H⋯N/N⋯H (19.3%) inter-actions. The optimized structure calculated using density functional theory at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated highest occupied mol-ecular orbital (HOMO) and lowest unoccupied mol-ecular orbital (LUMO) energy gap is 4.9266 eV.

Crystal structure and Hirshfeld surface analysis of 1-[(1-butyl-1H-1,2,3-triazol-4-yl)meth-yl]-3-methyl-quinoxalin-2(1H)-one.

The title compound, C16H19N5O, is built up from a planar quinoxalinone ring system linked through a methyl-ene bridge to a 1,2,3-triazole ring, which in turn carries an n-butyl substituent. The triazole ring is inclined by 67.09 (4)° to the quinoxalinone ring plane. In the crystal, the mol-ecules form oblique stacks along the a-axis direction through inter-molecular C-HTrz⋯NTrz (Trz = triazole) hydrogen bonds, and offset π-stacking inter-actions between quinoxalinone rings [centroid-centroid distance = 3.9107 (9) Å] and π-π inter-actions, which are associated pairwise by inversion-related C-HDhydqn⋯π(ring) (Dhydqn = di-hydro-quinoxaline) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (52.7%), H⋯N/N⋯H (18.9%) and H⋯C/C⋯H (17.0%) inter-actions.

Crystal structure and Hirshfeld surface analysis of ethyl 2-{4-[(3-methyl-2-oxo-1,2-di-hydro-quinoxalin-1-yl)meth-yl]-1H-1,2,3-triazol-1-yl}acetate.

The mol-ecule of the title compound, C16H17N5O3, is build up from two fused six-membered rings linked to a 1,2,3-triazole ring, which is attached to an ethyl azido-acetate group. The di-hydro-qinoxalinone portion is planar to within 0.0512 (12) Šand is oriented at a dihedral angle of 87.83 (5)° with respect to the pendant triazole ring. In the crystal, a combination of inter-molecular C-H⋯O and C-H⋯N hydrogen bonds together with slipped π-stacking [centroid-centroid distance = 3.7772 (12) Å] and C-H⋯π (ring) inter-actions lead to the formation of chains extending along the c-axis direction. Additional C-H⋯O hydrogen bonds link these chains into layers parallel to the bc plane and the layers are tied together by complementary π-stacking [centroid-centroid distance = 3.5444 (12) Å] inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (44.5%), H⋯O/O⋯H (18.8%), H⋯N/N⋯H (17.0%) and H⋯C/C⋯H (10.4%) inter-actions.