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1.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 8): 1280-1283, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31417807

RESUMO

In the title benzohydrazide derivative, C14H12N2O4, the azomethine C=N double bond has an E configuration. The hydrazide connecting bridge, (C=O)-(NH)-N=(CH), is nearly planar with C-C-N-N and C-N-N=C torsion angles of -177.33 (10) and -174.98 (12)°, respectively. The 4-hy-droxy-phenyl and 3,4-di-hydroxy-phenyl rings are slightly twisted, making a dihedral angle of 9.18 (6)°. In the crystal, mol-ecules are connected by N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network, while further consolidated via π-π inter-actions [centroid-centroid distances = 3.6480 (8) and 3.7607 (8) Å]. The conformation is compared to those of related benzyl-idene-4-hy-droxy-benzohydrazide derivatives.

2.
Sci Rep ; 9(1): 926, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700752

RESUMO

Imidazo[1,2-a]pyridine-based compounds are clinically important to the treatments of heart and circulatory failures, while many are under development for pharmaceutical uses. In this study, a series of imidazo[1,2-a]pyridine-based derivatives 2(a-o) were synthesized by reacting a-haloketones with 2-aminopyridines in a basic media at ambient temperature. Single crystal X-ray diffraction studies suggest that with low degree-of-freedom, the introduction of bulky adamantyl or electron-rich biphenyl moiety into the imidazopyridine derivatives will not affect its structural occupancy. Imidazo[1,2-a]pyridine-based derivatives with biphenyl side chain are potential AChE inhibitors. Compound 2h which bears a biphenyl side chain and methyl substituent at the position R4 of the imidazo[1,2-a]pyridine ring showed the strongest AChE inhibition with an IC50 value of 79 µM. However, imidazo[1,2-a]pyridine derivatives with phenyl side chain exhibit better BChE inhibition effect among the series. Compound 2j with 3,4-dichlorophenyl side chain and unsubstituted imidazo[1,2-a]pyridine ring appears to be the strongest BChE inhibitor with an IC50 value of 65 µM and good selectivity. The inhibitory effects of active compounds were further confirmed by computational molecular docking studies. The results unveiled that peripheral anionic sites of AChE and acyl pocket of BChE were the predominated binding sites for the subjected inhibitors.

3.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 1): 8-11, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30713724

RESUMO

A new polymorphic form of the title compound, C8H8O3, is described in the centrosymmetric monoclinic space group P21/c with Z' = 1 as compared to the first polymorph, which crystallizes with two conformers (Z' = 2) in the asymmetric unit in the same space group. In the crystal of the second polymorph, inversion dimers linked by O-H⋯O hydrogen bonds occur and these are linked into zigzag chains, propagating along the b-axis direction by C-H⋯O links. The crystal structure also features a weak π-π inter-action, with a centroid-to-centroid distance of 3.8018 (6) Å. The second polymorph of the title compound is less stable than the reported first polymorph, as indicated by its smaller calculated lattice energy.

4.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 1): 49-52, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30713732

RESUMO

In this study, a new monoclinic polymorph (space group C2/c) of 2,2'-methyl-enebis(isoindoline-1,3-dione), C17H10N2O4, is reported and compared to the previously reported triclinic polymorph (space group P ). Similarly, both polymorphs consist of a unique mol-ecule in the asymmetric unit (Z' = 1). The mol-ecular conformations of the two polymorphs are very similar, as shown by the r.m.s. deviation of 0.368 Š(excluding all H atoms). The inter-molecular inter-actions of both polymorphs are described along with the Hirshfeld surface analysis, and the lattice energies are calculated.

5.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 1): 53-57, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30713733

RESUMO

The mol-ecular structure of the title chalcone derivative, C15H10FNO3, is nearly planar and the mol-ecule adopts a trans configuration with respect to the C=C double bond. The nitro group is nearly coplanar with the attached benzene ring, which is nearly parallel to the second benzene ring. In the crystal, mol-ecules are connected by pairs of weak inter-molecular C-H⋯O hydrogen bonds into inversion dimers. The dimers are further linked by another C-H⋯O hydrogen bond and a C-H⋯F hydrogen bond into sheets parallel to (104). π-π inter-actions occur between the sheets, with a centroid-centroid distance of 3.8860 (11) Å. Hirshfeld surface analysis was used to investigate and qu-antify the inter-molecular inter-actions.

6.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 73(Pt 5): 879-890, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28980993

RESUMO

Hexamethylenetetramine-benzoic acid (1/2) (HBA) and hexamethylenetetramine-4-methylbenzoic acid (1/2) (HMBA) co-crystals undergo order-disorder structural phase transition from a low-temperature monoclinic crystal structure to a high-temperature orthorhombic crystal structure at the transition temperatures of 257.5 (5) K (Pn ↔ Fmm2) and 265.5 (5) K (P21/n ↔ Cmcm), respectively, using variable-temperature single-crystal X-ray diffraction analysis. The observed phase transitions were confirmed to be reversible first-order transitions as indicated by the sharp endothermic and exothermic peaks in the differential scanning calorimetry measurement. The three-molecule aggregate of HBA and HMBA consists of a hexamethylenetetramine molecule and two benzoic acid or two 4-methylbenzoic acid molecules, respectively. The acid molecules are ordered at the low-temperature phase and are equally disordered over two positions, which are related by a mirror symmetry, at the high-temperature phase. The two-dimensional supramolecular constructs common to both co-crystals are formed by three-molecule aggregates via weak intermolecular C-H...O and C-H...π interactions into molecular trilayers parallel to the ac plane with small XPac dissimilarity indices and parameters. The PIXEL interaction energies of all corresponding molecular contacts were calculated and the results are comparable between HBA and HMBA co-crystals, resulting in similar lattice energies and transition temperatures despite their two-dimensional isostructural relationship. The observed phase transitions of these two energetically similar co-crystals are triggered by similar mechanisms, i.e. the molecular rotator ordering and structural order-disorder transformation, which induced non-merohedral twinning with similar twin matrices in the low-temperature crystal form of both co-crystals.

7.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 7): 927-931, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28775853

RESUMO

The asymmetric unit of the title compound, C15H15N3O3·0.5H2O, comprises two 2-{[(4-iminiumyl-3-methyl-1,4-di-hydro-pyridin-1-yl)meth-yl]carbamo-yl}benzoate zwitterions (A and B) and a water mol-ecule. The dihedral angles between the pyridine and phenyl rings in the zwitterions are 53.69 (10) and 73.56 (11)° in A and B, respectively. In the crystal, mol-ecules are linked by N-H⋯O, O-H⋯O, C-H⋯O and C-H⋯π(ring) hydrogen bonds into a three-dimensional network. The crystal structure also features π-π inter-actions involving the centroids of the pyridine and phenyl rings [centroid-centroid distances = 3.5618 (12) Šin A and 3.8182 (14) Šin B].

8.
Molecules ; 22(6)2017 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-28629119

RESUMO

Adamantyl-based compounds are clinically important for the treatments of type 2 diabetes and for their antiviral abilities, while many more are under development for other pharmaceutical uses. This study focused on the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of adamantyl-based ester derivatives with various substituents on the phenyl ring using Ellman's colorimetric method. Compound 2e with a 2,4-dichloro electron-withdrawing substituent on the phenyl ring exhibited the strongest inhibition effect against AChE, with an IC50 value of 77.15 µM. Overall, the adamantyl-based ester with the mono-substituent at position 3 of the phenyl ring exhibited good AChE inhibition effects with an ascending order for the substituents: Cl < NO2 < CH3 < OCH3. Furthermore, compounds with electron-withdrawing groups (Cl and NO2) substituted at position 3 on their phenyl rings demonstrated stronger AChE inhibition effects, in comparison to their respective positional isomers. On the other hand, compound 2j with a 3-methoxyphenyl ring showed the highest inhibition effect against BChE, with an IC50 value of 223.30 µM. Molecular docking analyses were conducted for potential AChE and BChE inhibitors, and the results demonstrated that the peripheral anionic sites of target proteins were predominant binding sites for these compounds through hydrogen bonds and halogen interactions instead of hydrophobic interactions in the catalytic active site.


Assuntos
Acetilcolinesterase/química , Inibidores da Colinesterase/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Sítios de Ligação , Domínio Catalítico , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Concentração Inibidora 50 , Conformação Molecular , Ligação Proteica , Relação Estrutura-Atividade
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 184: 342-354, 2017 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-28528255

RESUMO

In the present work, the title chalcone, (2E)-3-(4-fluorophenyl)-1-(4-{[(1E)-(4-fluorophenyl) methylene]amino}phenyl)prop-2-en-1-one (abbreviated as FAMFC), was synthesized and structurally characterized by single-crystal X-ray diffraction. The compound is crystallized in the monoclinic system with non-centrosymmetric space group P21 and hence it satisfies the essential condition for materials to exhibit second-order nonlinear optical properties. The molecular structure was further confirmed by using FT-IR and 1H NMR spectroscopic techniques. The title crystal is transparent in the Vis-NIR region and has a direct band gap. The third-order nonlinear optical properties were investigated in solution (0.01M) by Z-scan technique using a continuous wave (CW) DPSS laser at the wavelength of 532nm. The title chalcone exhibited significant two-photon absorption (ß=35.8×10-5cmW-1), negative nonlinear refraction (n2=-0.18×10-8cm2W-1) and optical limiting (OL threshold=2.73kJcm-2) under the CW regime. In support of the experimental results, a comprehensive theoretical study was carried out on the molecule of FAMFC using density functional theory (DFT). The optimized geometries and frontier molecular orbitals were calculated by employing B3LYP/6-31+G level of theory. The optimized molecular structure was confirmed computationally by IR vibrational and 1H NMR spectral analysis. The experimental UV-Vis-NIR spectrum was interpreted using computational chemistry under time-dependent DFT. The static and dynamic NLO properties such as dipole moments (µ), polarizability (α), and first hyperpolarizabilities (ß) were computed by using finite field method. The obtained dynamic first hyperpolarizability ß(-2ω;ω,ω) at input frequency ω=0.04282a.u. is predicted to be 161 times higher than urea standard. The electronic excitation energies and HOMO-LUMO band gap for FAMFC were also evaluated by DFT. The experimental and theoretical results are in good agreement, and the NLO study suggests that FAMFC molecule can be a potential candidate in the nonlinear optical applications.

10.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 73(Pt 2): 285-295, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28362293

RESUMO

Isonicotinamide-4-methoxybenzoic acid co-crystal (1), C6H6N2O·C8H8O3, is formed through slow evaporation from methanol solution and it undergoes a first-order isosymmetry (monoclinic I2/a ↔ monoclinic I2/a) structural phase transition at Tc = 142.5 (5) K, which has been confirmed by an abrupt jump of crystallographic interaxial angle ß from variable-temperature single-crystal XRD and small heat hysteresis (6.25 K) in differential scanning calorimetry measurement. The three-dimensional X-ray crystal structures of (1) at the low-temperature phase (LTP) (100, 140 and 142 K) and the high-temperature phase (HTP) (143, 150, 200, 250 and 300 K) were solved and refined as a simple non-disordered model with final R[F2 > 2σ(F2)] ≃ 0.05. The asymmetric unit of (1) consists of crystallographically independent 4-methoxybenzoic acid (A) and isonicotinamide (B) molecules in both enantiotropic phases. Molecule A adopts a `near-hydroxyl' conformation in which the hydroxyl and methoxy groups are positioned on the same side. Both `near-hydroxyl' and `near-carbonyl' molecular conformations possess minimum conformational energies with an energy difference of < 0.15 kJ mol-1 from a potential energy surface scan. In the crystal, molecules are joined into linear ABBA arrays by intermolecular N-H...O and O-H...N hydrogen bonds which were preserved in both phases. However, these ABBA arrays are displaced from planarity upon LTP-to-HTP transition and the changes in inter-array interactions are observed in two-dimensional fingerprint plots of their Hirshfeld surfaces. The PIXEL energies of each molecular pair in both phases were calculated to investigate the difference in intermolecular interaction energies before and after the displacement of ABBA arrays from planarity, which directly leads to the single-crystal-to-single-crystal phase transition of (1).


Assuntos
Éteres de Hidroxibenzoatos/química , Niacinamida/química , Varredura Diferencial de Calorimetria , Cristalização , Cristalografia por Raios X , Ligação de Hidrogênio , Hidroxibenzoatos/química , Conformação Molecular , Transição de Fase , Temperatura , Termodinâmica , Temperatura de Transição
11.
PLoS One ; 12(2): e0170117, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28241010

RESUMO

Biphenyl-based compounds are clinically important for the treatments of hypertension and inflammatory, while many more are under development for pharmaceutical uses. In the present study, a series of 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl benzoates, 2(a-q), and 2-([1,1'-biphenyl]-4-yl)-2-oxoethyl pyridinecarboxylate, 2(r-s) were synthesized by reacting 1-([1,1'-biphenyl]-4-yl)-2-bromoethan-1-one with various carboxylic acids using potassium carbonate in dimethylformamide at ambient temperature. Single-crystal X-ray diffraction studies revealed a more closely packed crystal structure can be produced by introduction of biphenyl moiety. Five of the compounds among the reported series exhibited significant anti-tyrosinase activities, in which 2p, 2r and 2s displayed good inhibitions which are comparable to standard inhibitor kojic acid at concentrations of 100 and 250 µg/mL. The inhibitory effects of these active compounds were further confirmed by computational molecular docking studies and the results revealed the primary binding site is active-site entrance instead of inner copper binding site which acted as the secondary binding site.


Assuntos
Compostos de Bifenilo/síntese química , Ésteres/síntese química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Algoritmos , Sítios de Ligação , Domínio Catalítico , Cobre/química , Cristalografia por Raios X , Análise dos Mínimos Quadrados , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/química , Pironas/química , Software , Solventes , Espectrofotometria Infravermelho , Temperatura , Difração de Raios X
12.
Acta Crystallogr C Struct Chem ; 72(Pt 12): 971-980, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27918299

RESUMO

As a function of temperature, the hexamethylenetetramine-2-methylbenzoic acid (1/2) cocrystal, C6H12N4·2C8H8O2, undergoes a reversible structural phase transition. The orthorhombic high-temperature phase in the space group Pccn has been studied in the temperature range between 165 and 300 K. At 164 K, a t2 phase transition to the monoclinic subgroup P21/c space group occurs; the resulting twinned low-temperature phase was investigated in the temperature range between 164 and 100 K. The domains in the pseudomerohedral twin are related by a twofold rotation corresponding to the matrix (100/0-10/00-1. Systematic absence violations represent a sensitive criterium for the decision about the correct space-group assignment at each temperature. The fractional volume contributions of the minor twin domain in the low-temperature phase increases in the order 0.259 (2) → 0.318 (2) → 0.336 (2) → 0.341 (3) as the temperature increases in the order 150 → 160 → 163 → 164 K. The transformation occurs between the nonpolar point group mmm and the nonpolar point group 2/m, and corresponds to a ferroelastic transition or to a t2 structural phase transition. The asymmetric unit of the low-temperature phase consists of two hexamethylenetetramine molecules and four molecules of 2-methylbenzoic acid; it is smaller by a factor of 2 in the high-temperature phase and contains two half molecules of hexamethylenetetramine, which sit across twofold axes, and two molecules of the organic acid. In both phases, the hexamethylenetetramine residue and two benzoic acid molecules form a three-molecule aggregate; the low-temperature phase contains two of these aggregates in general positions, whereas they are situated on a crystallographic twofold axis in the high-temperature phase. In both phases, one of these three-molecule aggregates is disordered. For this disordered unit, the ratio between the major and minor conformer increases upon cooling from 0.567 (7):0.433 (7) at 170 K via 0.674 (6):0.326 (6) and 0.808 (5):0.192 (5) at 160 K to 0.803 (6):0.197 (6) and 0.900 (4):0.100 (4) at 150 K, indicating temperature-dependent dynamic molecular disorder. Even upon further cooling to 100 K, the disorder is retained in principle, albeit with very low site occupancies for the minor conformer.

13.
Molecules ; 20(10): 18827-46, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26501248

RESUMO

Adamantyl-based compounds are commercially important in the treatments for neurological conditions and type-2 diabetes, aside from their anti-viral abilities. Their values in drug design are chronicled as multi-dimensional. In the present study, a series of 2-(adamantan-1-yl)-2-oxoethyl benzoates, 2(a-q), and 2-(adamantan-1-yl)-2-oxoethyl 2-pyridinecarboxylate, 2r, were synthesized by reacting 1-adamantyl bromomethyl ketone with various carboxylic acids using potassium carbonate in dimethylformamide medium at room temperature. Three-dimensional structures studied using X-ray diffraction suggest that the adamantyl moiety can serve as an efficient building block to synthesize 2-oxopropyl benzoate derivatives with synclinal conformation with a looser-packed crystal packing system. Compounds 2a, 2b, 2f, 2g, 2i, 2j, 2m, 2n, 2o, 2q and 2r exhibit strong antioxidant activities in the hydrogen peroxide radical scavenging test. Furthermore, three compounds, 2p, 2q and 2r, show good anti-inflammatory activities in the evaluation of albumin denaturation.


Assuntos
Adamantano/análogos & derivados , Adamantano/síntese química , Albuminas/química , Anti-Inflamatórios/síntese química , Cristalografia por Raios X , Ésteres , Sequestradores de Radicais Livres/síntese química , Conformação Molecular , Desnaturação Proteica
14.
Molecules ; 20(9): 16566-81, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26378514

RESUMO

A series of five new 2-(1-benzofuran-2-yl)-2-oxoethyl 4-(un/substituted)benzoates 4(a-e), with the general formula of C8H5O(C=O)CH2O(C=O)C6H4X, X = H, Cl, CH3, OCH3 or NO2, was synthesized in high purity and good yield under mild conditions. The synthesized products 4(a-e) were characterized by FTIR, ¹H-, (13)C- and ¹H-(13)C HMQC NMR spectroscopic analysis and their 3D structures were confirmed by single-crystal X-ray diffraction studies. These compounds were screened for their antimicrobial and antioxidant activities. The tested compounds showed antimicrobial ability in the order of 4b < 4a < 4c < 4d < 4e and the highest potency with minimum inhibition concentration (MIC) value of 125 µg/mL was observed for 4e. The results of antioxidant activities revealed the highest activity for compound 4e (32.62% ± 1.34%) in diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 4d (31.01% ± 4.35%) in ferric reducing antioxidant power (FRAP) assay and 4a (27.11% ± 1.06%) in metal chelating (MC) activity.


Assuntos
Antioxidantes/química , Antioxidantes/síntese química , Benzofuranos/química , Ésteres/química , Ésteres/síntese química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Cristalografia por Raios X , Ésteres/farmacologia , Testes de Sensibilidade Microbiana , Oxirredução/efeitos dos fármacos , Difração de Raios X
15.
Molecules ; 18(2): 2386-96, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23429377

RESUMO

Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, namely formic acid, acetic acid and propionic acid. The structures were characterized by X-ray single crystal structure determination. The dihedral angles formed between the pyrazole and the fluoro-substituted rings are 4.64(7)° in 1, 5.3(4)° in 2 and 4.89(6)° in 3. In 4, the corresponding angles for molecules A and molecules B are 10.53(10)° and 9.78(10)°, respectively.


Assuntos
Pirazóis/química , Pirazóis/síntese química , Cristalografia por Raios X , Ligação de Hidrogênio , Conformação Molecular
16.
Int J Mol Sci ; 14(1): 1667-83, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23322018

RESUMO

Flavodoxins, which exist widely in microorganisms, have been found in various pathways with multiple physiological functions. The flavodoxin (Fld) containing the cofactor flavin mononucleotide (FMN) from sulfur-reducing bacteria Desulfovibrio gigas (D. gigas) is a short-chain enzyme that comprises 146 residues with a molecular mass of 15 kDa and plays important roles in the electron-transfer chain. To investigate its structure, we purified this Fld directly from anaerobically grown D. gigas cells. The crystal structure of Fld, determined at resolution 1.3 Å, is a dimer with two FMN packing in an orientation head to head at a distance of 17 Å, which generates a long and connected negatively charged region. Two loops, Thr59-Asp63 and Asp95-Tyr100, are located in the negatively charged region and between two FMN, and are structurally dynamic. An analysis of each monomer shows that the structure of Fld is in a semiquinone state; the positions of FMN and the surrounding residues in the active site deviate. The crystal structure of Fld from D. gigas agrees with a dimeric form in the solution state. The dimerization area, dynamic characteristics and structure variations between monomers enable us to identify a possible binding area for its functional partners.


Assuntos
Desulfovibrio gigas/enzimologia , Flavodoxina/química , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Sequência de Aminoácidos , Sítios de Ligação/genética , Cristalografia por Raios X , Desulfovibrio gigas/genética , Transporte de Elétrons , Mononucleotídeo de Flavina/química , Mononucleotídeo de Flavina/metabolismo , Flavodoxina/genética , Flavodoxina/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Ligação Proteica , Homologia de Sequência de Aminoácidos
17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2988-9, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125763

RESUMO

In the title compound, C(14)H(15)N(5)O(4), the central -C=N-N-C(=O)-C- bridge is nearly planar [maximum deviation = 0.037 (1) Å] and forms dihedral angles of 7.37 (9) and 73.33 (5)°, respectively, with the benzene and imidazole rings. The dihedral angle between the benzene and imidazole rings is 66.08 (9)°. The meth-oxy and nitro groups are nearly coplanar with the benzene and imidazole rings, respectively, with a C-O-C-C torsion angle of 5.9 (2)° and an O-N-C-C angle of -0.2 (2)°. In the crystal, mol-ecules are linked by a pair of N-H⋯O hydrogen bonds with an R(2) (2)(8) ring motif, forming an inversion dimer. The dimers are further inter-connected by C-H⋯O hydrogen bonds into a sheet parallel to the (111) plane. A C-H⋯π inter-action is also observed between the sheets.

18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o3055-6, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125816

RESUMO

In the title compound, C(22)H(19)N(5)OS·H(2)O, the naphthalene ring system and the benzene ring [dihedral angle = 85.19 (8)°] make dihedral angles of 87.02 (9) and 14.41 (10)°, respectively, with the pyrazole ring. The mean plane through the 2-methyl-enehydrazinecarbothio-amide group [C-N-N-C(=S)-N; maximum deviation = 0.022 (1) Å] is slightly twisted from the pyrazole ring [dihedral angle = 5.60 (11)°]. In the crystal, mol-ecules are linked by N-H⋯S, N-H⋯O, O-H⋯S, O-H⋯N and C-H⋯S hydrogen bonds into sheets parallel to the ab plane. π-π inter-actions are also observed [centroid-to-centroid distances = 3.7778 (12) and 3.7010 (12) Å].

19.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2619-20, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969521

RESUMO

The asymmetric unit of the title compound, C(27)H(16)F(2)N(2)O(4), consists of two crystallographically independent mol-ecules (A and B). In mol-ecule B, the isoindoline-1,3-dione ring system is disordered over two set of sites with a site-occupancy ratio of 0.658 (12):0.342 (12). In mol-ecule A, the fluoro-substituted benzene rings make dihedral angles of 18.36 (8) and 46.37 (8)° with the central benzene ring, whereas the corresponding angles are 40.90 (8) and 52.89 (9)° in mol-ecule B. The isoindoline ring system in mol-ecule A and the major and minor components of the disordered isoindoline ring system in mol-ecule B make dihedral angles of 58.50 (4), 54.13 (16) and 70.01 (28) °, respectively, with their attached benzene rings, linked through the amide group. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring in each mol-ecule. In the crystal, mol-ecules are linked by N-H⋯O, C-H⋯F and C-H⋯O hydrogen bonds into sheets lying parallel to the bc plane. The crystal studied was a non-merohedral twin with a refined twin component ratio of 0.9316 (8):0.0684 (8).

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 9): o2621, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22969522

RESUMO

The asymmetric unit of the title mol-ecular salt, C(19)H(15)N(4) (+)·I(-), contains four 2,3,5-triphenyl-2H-tetra-zol-3-ium cations and five iodide anions, with two of the latter lying on crystallographic inversion centres. In each cation, the tetra-zole ring is essentially planar (r.m.s. deviations = 0.004-0.007 Å). The dihedral angles between the tetra-zole ring and its three attached benzene rings in the four independent cations are: 12.9 (4), 67.0 (4), 48.1 (4); 20.8 (4), 51.1 (4), 62.3 (4); 11.4 (4), 52.3 (4), 47.3 (4) and 6.0 (4), 85.7 (4), 43.5 (4)°. A C-H⋯I hydrogen bond and C-H⋯π inter-actions are observed in the crystal.

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