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1.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 4): 423-429, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38584744

RESUMEN

In the title mol-ecule, C21H23N3O3, the imidazolidine ring slightly deviates from planarity and the morpholine ring exhibits the chair conformation. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds form helical chains of mol-ecules extending parallel to the c axis that are connected by C-H⋯π(ring) inter-actions. A Hirshfeld surface analysis reveals that the most important contributions for the crystal packing are from H⋯H (55.2%), H⋯C/C⋯H (22.6%) and H⋯O/O⋯H (20.5%) inter-actions. The volume of the crystal voids and the percentage of free space were calculated to be 236.78 Å3 and 12.71%, respectively. Evaluation of the electrostatic, dispersion and total energy frameworks indicates that the stabilization is dominated by the nearly equal electrostatic and dispersion energy contributions. The DFT-optimized mol-ecular structure at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined mol-ecular structure in the solid state. Moreover, the HOMO-LUMO behaviour was elucidated to determine the energy gap.

2.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 2): 232-239, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38333114

RESUMEN

The in-do-line portion of the title mol-ecule, C16H13NO2, is planar. In the crystal, a layer structure is generated by C-H⋯O hydrogen bonds and C-H⋯π(ring), π-stacking and C=O⋯π(ring) inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (43.0%), H⋯C/C⋯H (25.0%) and H⋯O/O⋯H (22.8%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. The volume of the crystal voids and the percentage of free space were calculated to be 120.52 Å3 and 9.64%, respectively, showing that there is no large cavity in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated by the dispersion energy contributions in the title compound. Moreover, the DFT-optimized structure at the B3LYP/6-311G(d,p) level is compared with the experimentally determined mol-ecular structure in the solid state.

3.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 11): 1033-1036, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37936861

RESUMEN

In the title compound, C20H28BrNO2, the indoline portion is almost planar and the 12-bromo-dodecyl chain adopts an all-trans conformation apart from the gauche terminal C-C-C-Br fragment. A micellar-like structure is generated in the crystal by C-H⋯O hydrogen bonds and π-stacking inter-actions between indolinedione head groups and inter-calation of the 12-bromo-dodecyl tails. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (58.9%), H⋯O/O⋯H (17.9%) and H⋯Br/Br⋯H (9.5%) contacts. A density functional theory (DFT) optimized structure at the B3LYP/ 6-311 G(d,p) level shows good agreement with the experimentally determined mol-ecular structure in the solid state.

4.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 10): 895-898, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37817954

RESUMEN

The asymmetric unit of the title compound, C12H13N3O4, consists of two mol-ecules differing to a small degree in their conformations. In the crystal, layers of mol-ecules are connected by weak C-H⋯O hydrogen bonds and slipped π-stacking inter-actions. These layers lie parallel to (10) and are stacked along the normal to that plane. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing arise from H⋯H (43.5%) and H⋯O/O⋯H (30.8%) contacts. The density functional theory (DFT) optimized structure of the title compound at the B3LYP/ 6-311 G(d,p) level agrees well with the experimentally determined mol-ecular structure in the solid state.

5.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 10): 883-889, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37817963

RESUMEN

In the title mol-ecule, C14H11NO3, the di-hydro-quinoline core deviates slightly from planarity, indicated by the dihedral angle of 1.07 (3)° between the two six-membered rings. In the crystal, layers of mol-ecules almost parallel to the bc plane are formed by C-H⋯O hydro-gen bonds. These are joined by π-π stacking inter-actions. A Hirshfeld surface analysis revealed that the most important contributions to the crystal packing are from H⋯H (36.0%), H⋯C/C⋯H (28.9%) and H⋯O/O⋯H (23.5%) inter-actions. The evaluation of the electrostatic, dispersion and total energy frameworks indicates that the stabilization is dominated by the dispersion energy contribution. Moreover, the mol-ecular structure optimized by density functional theory (DFT) at the B3LYP/6-311G(d,p) level is com-pared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

6.
Molecules ; 28(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37049960

RESUMEN

5-bromopyridine-2,3-diamine reacted with benzaldehyde to afford the corresponding 6-Bromo-2-phenyl-3H-imidazo[4,5-b]pyridine (1). The reaction of the latter compound (1) with a series of halogenated derivatives under conditions of phase transfer catalysis solid-liquid (CTP) allows the isolation of the expected regioisomers compounds (2-8). The alkylation reaction of (1) gives, each time, two regioisomers, N3 and N4; in the case of ethyl bromoactate, the reaction gives, at the same time, the three N1, N3 and N4 regioisomers. The structures of synthesized compounds were elucidated on the basis of different spectral data (1H NMR, 13C NMR), X-Ray diffraction and theoretical study using the DFT method, and confirmed for each compound. Hirshfeld surface analysis was used to determine the intermolecular interactions responsible for the stabilization of the molecule. Density functional theory was used to optimize the compounds, and the HOMO-LUMO energy gap was calculated, which was used to examine the inter/intra molecular charge transfer. The molecular electrostatic potential map was calculated to investigate the reactive sites that were present in the molecule. In order to determine the potential mode of interactions with DHFR active sites, the three N1, N3 and N4 regioisomers were further subjected to molecular docking study. The results confirmed that these analogs adopted numerous important interactions, with the amino acid of the enzyme being targeted. Thus, the most docking efficient molecules, 2 and 4, were tested in vitro for their antibacterial activity against Gram-positive bacteria (Bacillus cereus) and Gram-negative bacteria (Escherichia coli). Gram-positive bacteria were more sensitive to the action of these compounds compared to the Gram-negative, which were much more resistant.


Asunto(s)
Antiinfecciosos , Simulación del Acoplamiento Molecular , Conformación Molecular , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/química , Bacterias Grampositivas , Piridinas/farmacología , Piridinas/química
7.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 12): 1183-1189, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38313136

RESUMEN

In the title mol-ecule, C7H7N3O, the pyrimidine ring is essentially planar, with the propynyl group rotated out of this plane by 15.31 (4)°. In the crystal, a tri-periodic network is formed by N-H⋯O, N-H⋯N and C-H⋯O hydrogen-bonding and slipped π-π stacking inter-actions, leading to narrow channels extending parallel to the c axis. Hirshfeld surface analysis of the crystal structure reveals that the most important contributions for the crystal packing are from H⋯H (36.2%), H⋯C/C⋯H (20.9%), H⋯O/O⋯H (17.8%) and H⋯N/N⋯H (12.2%) inter-actions, showing that hydrogen-bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicates that the stabilization is dominated by the electrostatic energy contributions. The mol-ecular structure optimized by density functional theory (DFT) calculations at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined structure in the solid state. The HOMO-LUMO behaviour was also elucidated to determine the energy gap.

8.
Molecules ; 27(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35744970

RESUMEN

Pomegranate variety properties are important not only to demonstrate their diversity but also to satisfy the current market need for high-quality fruits. This study aims to characterize pomological and physico-chemical features as well as the antioxidant capacity of Moroccan local cultivars (Djeibi, Mersi, Sefri 1 and Sefri 2) compared to the imported ones (Mollar de Elche and Hicaz). The pomological characteristics of varieties were relatively diverse. The juice varieties (PJ) displayed a marketed variability in organoleptic and quality properties, such as the flavor, juice yield, and micro/macronutrients contents. Interrelationships among the analyzed properties and PJ varieties were investigated by principal component analysis (PCA). Dimension of the data set was reduced to two components by PCA accounting for 64.53% of the variability observed. The rinds varieties (PR) were studied for their total phenolics, flavonoids, and condensed tannins quantifications. PR varieties extracts exhibited different levels of free radical scavenging activity and local varieties revealed a greater potential with stability over time. The HPLC-DAD analyses of PR extracts revealed (+) catechin as the major compound, where the highest content was found for the local varieties. The SEC analysis showed the molecular weight distribution of phenolic compounds with a high size of condensed tannins formed by the polymerization of the catechin monomer. Given these properties, this research provides an easy selection of high-quality fruits as potential candidates for local market needs.


Asunto(s)
Catequina , Lythraceae , Granada (Fruta) , Proantocianidinas , Antioxidantes/química , Catequina/análisis , Frutas/química , Lythraceae/química , Marruecos , Fenoles/análisis , Extractos Vegetales/química , Proantocianidinas/análisis , Sensación
9.
Acta Crystallogr E Crystallogr Commun ; 78(Pt 4): 425-432, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35492275

RESUMEN

In the title compound, C12H10ClNO3, the di-hydro-quinoline moiety is not planar with a dihedral angle between the two ring planes of 1.61 (6)°. An intra-molecular C-H⋯O hydrogen bond helps to establish the rotational orientation of the carboxyl group. In the crystal, sheets of mol-ecules parallel to (10) are generated by C-H⋯O and C-H⋯Cl hydrogen bonds, and are stacked through slipped π-stacking inter-actions between inversion-related di-hydro-quinoline units. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (34.2%), H⋯O/O⋯H (19.9%), H⋯Cl/Cl⋯H (12.8%), H⋯C/C⋯H (10.3%) and C⋯C (9.7%) inter-actions. Computational chemistry indicates that in the crystal, the C-H⋯Cl hydrogen-bond energy is -37.4 kJ mol-1, while the C-H⋯O hydrogen-bond energies are -45.4 and -29.2 kJ mol-1. An evaluation of the electrostatic, dispersion and total energy frameworks revealed that the stabilization is dominated via the dispersion energy contribution. Density functional theory (DFT) optimized structures at the B3LYP/6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state, and the HOMO-LUMO behaviour was elucidated to determine the energy gap.

10.
RSC Adv ; 12(7): 4175-4186, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35425412

RESUMEN

An environmental approach for leather manufacturing is primordial to provide a global strategy towards more sustainable biomaterials and greener tanning processing methods. The ability of collagen as a principal component of skin to combine natural phenolic compounds, especially vegetable tannins, has been proven to be eco-friendly and manageable, while making good improvement to leather properties in the tanning process. In this study, we have used pomegranate phenolic compounds and insoluble collagen as a model system to examine the effects of tanning steps on the conformation of collagen. In detail, efficient modified extraction of pure insoluble collagen (IC) was presented. The IC was successfully identified using XRD, FTIR, SEM-EDS and TGA-DSC to verify the triple helix structure, morphology and thermal properties. As a result, the as-extracted collagen exhibits a high purity, preserving the triple helix collagen structure. Besides, the IC was modified using extracted pomegranate phenolic compounds, resulting in Crosslinked Insoluble Collagen (CIC). Characterization techniques were also performed to confirm the crosslinking process. Indeed, by comparing the FTIR vibrational spectra of IC and CIC, slight shifts of amide groups were observed, indicating the presence of inter and intramolecular interaction between IC functional groups and pomegranate phenolic compounds. Moreover, the morphology of CIC was changed. XRD analysis confirms collagen conformational integrity. Finally, thermal properties were improved. The temperature at 50% weight loss (T°50) increases from 344.54 °C to 375.53 °C. CIC multifunctionality allowed utilizing pomegranate phenolic compound extracts as a tanning agent in leather processing.

11.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 8): 1361-1364, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32844030

RESUMEN

The title quinoxaline mol-ecule, C23H20N2O2, is not planar, the dihedral angle angle between the mean planes of the benzene rings being 72.54 (15)°. In the crystal, mol-ecules are connected into chains extending parallel to (10) by weak C-H⋯O hydrogen bonds. Weak C-H⋯π inter-actions link the chains, forming a three-dimensional network structure. Hirshfeld surface analysis revealed that the most important contributions for the crystal packing are from H⋯H (48.7%), H⋯C/C⋯H (32.0%), H⋯O/O⋯H (15.4%), C⋯C (1.9%), H⋯N/N⋯H (1.1%) contacts.

12.
Arch Pharm (Weinheim) ; 353(12): e2000173, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32812268

RESUMEN

To develop potent and selective anticancer agents, a series of novel polysubstituted indazoles was synthesized and evaluated for their in vitro antiproliferative and apoptotic activities against two selected human cancer cell lines (A2780 and A549). Several compounds showed an interesting antiproliferative activity, with IC50 values ranging from 0.64 to 17 µM against both cell lines. The most active indazoles were then tested in different pharmacological dilution conditions, adding five new cell lines (A2780, A549, IMR32, MDA-MB-231, and T47D) as targets, confirming their antiproliferative activity. Furthermore, selected compounds were able to trigger apoptosis to a significant extent and to cause, in part, a block of cells in the S phase of the cell cycle, with a concomitant decrease of cells in the G2/M and/or G0/G1 phases and the generation of hypodiploid peaks. However, molecule 7d caused a great increase of cells in G2/M and the appearance of polyploid cells. Altogether, our results suggest a good pharmacological activity for our selected polysubstituted indazoles, which are suggestive of a preferential mechanism of action as cell cycle-specific antimetabolites or as an inhibitor of enzyme activities involved in DNA synthesis, except for 7d, which, on the contrary, seems to have a mechanism involving the microtubule system.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Indazoles/farmacología , Neoplasias/tratamiento farmacológico , Células A549 , Antineoplásicos/síntesis química , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Indazoles/síntesis química , Concentración 50 Inhibidora , Estructura Molecular , Neoplasias/patología , Relación Estructura-Actividad
13.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 5): 677-682, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32431932

RESUMEN

The title compound, C24H30Br2N4O2, consists of a 2-(4-nitro-phen-yl)-4H-imidazo[4,5-b]pyridine entity with a 12-bromo-dodecyl substituent attached to the pyridine N atom. The middle eight-carbon portion of the side chain is planar to within 0.09 (1) Šand makes a dihedral angle of 21.9 (8)° with the mean plane of the imidazolo-pyridine moiety, giving the mol-ecule a V-shape. In the crystal, the imidazolo-pyridine units are associated through slipped π-π stacking inter-actions together with weak C-HPyr⋯ONtr and C-HBrmdc-yl⋯ONtr (Pyr = pyridine, Ntr = nitro and Brmdcyl = bromo-dodec-yl) hydrogen bonds. The 12-bromo-dodecyl chains overlap with each other between the stacks. The terminal -CH2Br group of the side chain shows disorder over two resolved sites in a 0.902 (3):0.098 (3) ratio. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H⋯H (48.1%), H⋯Br/Br⋯H (15.0%) and H⋯O/O⋯H (12.8%) inter-actions. The optimized mol-ecular structure, 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 HOMO-LUMO behaviour was elucidated to determine the energy gap.

14.
ScientificWorldJournal ; 2019: 2630537, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31885523

RESUMEN

Snails were fed with three medicinal plants belonging to the Lamiaceae family (rosemary, sage, and peppermint) in order to test their effects on those animals with high nutritive values. The media of raising were flour containing different percentages of the cited plants ranging from 1% to 9%. The feed had benefits on the raised snails depending on the plant and its percentage. Minerals in those aromatic plants, especially zinc and magnesium, had their effect on protein synthesis in snails fed with those plant percentages. Rosemary was the most profitable plant with the highest protein amount, the lowest mortality rate, and reduced microbial charge. Furthermore, it was a good regulator of the specific catalase activity which confirmed the role of the antioxidant activity of rosemary during raising snails.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Plantas Medicinales/química , Caracoles/crecimiento & desarrollo , Agricultura/métodos , Animales , Magnesio/análisis , Mentha piperita/química , Rosmarinus/química , Salvia officinalis/química , Caracoles/fisiología , Zinc/análisis
15.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 11): 1753-1758, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31709103

RESUMEN

The title com-pound, C24H24N2O6, consists of ethyl 2-(1,2,3,4-tetra-hydro-2-oxo-quinolin-1-yl)acetate and 4-[(2-eth-oxy-2-oxoeth-yl)(phen-yl)carbomoyl] units, where the oxo-quinoline unit is almost planar and the acetate substituent is nearly perpendicular to its mean plane. In the crystal, C-HOxqn⋯OEthx and C-HPh-yl⋯OCarbx (Oxqn = oxoquinolin, Ethx = eth-oxy, Phyl = phenyl and Carbx = carboxyl-ate) weak hydrogen bonds link the mol-ecules into a three-dimensional network sturucture. A π-π inter-action between the constituent rings of the oxo-quinoline unit, with a centroid-centroid distance of 3.675 (1) Šmay further stabilize the structure. Both terminal ethyl groups are disordered over two sets of sites. The ratios of the refined occupanies are 0.821 (8):0.179 (8) and 0.651 (18):0.349 (18). The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (53.9%), H⋯O/O⋯H (28.5%) and H⋯C/C⋯H (11.8%) inter-actions. Weak inter-molecular hydrogen-bond inter-actions and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Density functional theory (DFT) geometric optimized structures at the B3LYP/6-311G(d,p) level are com-pared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO mol-ecular orbital behaviour was elucidated to determine the energy gap.

16.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 10): 1411-1417, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31636967

RESUMEN

The title compound, C15H12ClNO3, consists of a 1,2-di-hydro-quinoline-4-carb-oxyl-ate unit with 2-chloro-ethyl and propynyl substituents, where the quinoline moiety is almost planar and the propynyl substituent is nearly perpendicular to its mean plane. In the crystal, the mol-ecules form zigzag stacks along the a-axis direction through slightly offset π-stacking inter-actions between inversion-related quinoline moieties which are tied together by inter-molecular C-HPrpn-yl⋯OCarbx and C-HChlethy⋯OCarbx (Prpnyl = propynyl, Carbx = carboxyl-ate and Chlethy = chloro-eth-yl) hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (29.9%), H⋯O/O⋯H (21.4%), H⋯C/C⋯ H (19.4%), H⋯Cl/Cl⋯H (16.3%) and C⋯C (8.6%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, the C-HPrpn-yl⋯OCarbx and C-HChlethy⋯OCarbx hydrogen bond energies are 67.1 and 61.7 kJ mol-1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

17.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 9): 1372-1378, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31523469

RESUMEN

The title compound, C14H15BrClNO4, consists of a 5-bromo-indoline-2,3-dione unit linked to a 1-{2-[2-(2-chloro-eth-oxy)eth-oxy]eth-yl} moiety. In the crystal, a series of C-H⋯O hydrogen bonds link the molecules to form a supramolecular three-dimensional structure, enclosing R 2 2(8), R 2 2(12), R 2 2(18) and R 2 2(22) ring motifs. π-π contacts between the five-membered dione rings may further stabilize the structure, with a centroid-centroid distance of 3.899 (2) Å. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (28.1%), H⋯O/O⋯H (23.5%), H⋯Br/Br⋯H (13.8%), H⋯Cl/Cl⋯H (13.0%) and H⋯C/C⋯H (10.2%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Density functional theory (DFT) optimized structures at the B3LYP/6-311G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap. The chloro-eth-oxy-ethoxyethyl side chain atoms are disordered over two sets of sites with an occupancy ratio of 0.665 (8):0.335 (6).

18.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 7): 951-956, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31392002

RESUMEN

The title compound, C21H16N2O2, consists of an imidazolidine unit linked to two phenyl rings and two prop-2-yn-1-yl moieties. The imidazolidine ring is oriented at dihedral angles of 79.10 (5) and 82.61 (5)° with respect to the phenyl rings, while the dihedral angle between the two phenyl rings is 62.06 (5)°. In the crystal, inter-molecular C-HProp⋯OImdzln (Prop = prop-2-yn-1-yl and Imdzln = imidazolidine) hydrogen bonds link the mol-ecules into infinite chains along the b-axis direction. Two weak C-HPhen⋯π inter-actions are also observed. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (43.3%), H⋯C/C⋯H (37.8%) and H⋯O/O⋯H (18.0%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that the C-HProp⋯OImdzln hydrogen-bond energy in the crystal is -40.7 kJ mol-1. Density functional theory (DFT) optimized structures at the B3LYP/6-311G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

19.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 1): 43-48, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30713731

RESUMEN

The title compound, C15H11BrClN3, is built up from a planar imidazo[4,5-b]pyridine unit linked to phenyl and allyl substituents. The allyl substituent is rotated significantly out of the imidazo[4,5-b]pyridine plane, while the benzene ring is inclined by 3.84 (6)° to the ring system. In the crystal, mol-ecules are linked via a pair of weak inter-molecular C-H⋯N hydrogen bonds, forming an inversion dimer with an R 2 2(20) ring motif. The dimers are further connected by π-π stacking inter-actions between the imidazo[4,5-b]pyridine ring systems [centroid-centroid distances = 3.7161 (13) and 3.8478 (13) Å]. The important contributions to the Hirshfeld surface are H⋯H (35.9%), H⋯Cl/Cl⋯H (15.0%), H⋯C/C⋯H (12.4%), H⋯Br/Br⋯H (10.8%), H⋯N/N⋯H (7.5%), C⋯Br/Br⋯C (5.9%), C⋯C (5.5%) and C⋯N/N⋯C (4.0%) contacts.

20.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 10): o735-6, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26594449

RESUMEN

In the title compound, C17H19ClN4O5, the benzimidazole fused-ring system is essentially planar, the maximum deviation from the mean plane being 0.06 (1) Å. Both oxazolidine rings are nearly planar, the maximum deviations from the mean planes are 0.071 (13) and 0.070 (10) Å. The dihedral angle between the mean planes of the oxazolidine rings is 69.9 (7)°. The benzimidazole mean plane makes the dihedral angles of 43.9 (6) and 45.6 (6)° with the two oxazolidine rings. In the crystal, the mol-ecules are linked together by weak C-H⋯O hydrogen bonds building zigzag tapes running along the c axis. The Cl atom is split over two positions with an occupancy ratio of 0.567 (7):0.433 (7). This means that the reaction yields two isomers, A and B; the A component has the Cl-atom substituent in the 5-position of the benzimidazolone ring and the B component has the Cl atom in the 6-position. The two isomers form the disordered co-crystal, with a nearly half Cl atom in each of them, as indicated by the occupancy ratio. The crystal structure was refined as an inversion twin.

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