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1-Methyl-2-[(E)-2,4,5-trimethoxystyryl]pyridinium benzenesulfonate monohydrate  [cached]
Hoong-Kun Fun,Suchada Chantrapromma,Pumsak Ruanwas,Teerasak Anantapong
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812007805
Abstract: The asymmetric unit of the title compound, C17H20NO3+·C6H5O3S ·H2O, comprises two 1-methyl-2-[(E)-2,4,5-trimethoxystyryl]pyridinium cations, two benzenesulfonate anions and two water molecules. The cations exist in the E conformation with respect to the C=C bond; one cation is essentially planar while the other is slightly twisted, the dihedral angles between the pyridinium and phenyl rings being 1.23 (14) and 6.64 (13)°, respectively. In the crystal, cations, anions and water molecules are linked by O—H...O hydrogen bonds and weak C—H...O interactions into chains along the b axis. π–π interactions with centroid–centroid distances in the range 3.5557 (16)–3.6876 (16) are observed. C—H...π interactions and a C...O short contact [2.94 (4) ] are also observed.
2-Methylcarbamoyl-4-{4-[3-(trifluoromethyl)benzamido]phenoxy}pyridinium 4-methylbenzenesulfonate monohydrate  [cached]
Zhao Wang,Na-Na Meng,Ting-Ting Huang,Yong-Kui Zhang
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536809055603
Abstract: The asymmetric unit of the title compound, C21H17F3N3O3+·C7H7O3S ·H2O, contains two formula units. In one of the cations, the pyridinium and trifluoromethyl benzene rings form dihedral angles of 87.42 (8) and 45.92 (8)°, respectively, with the central benzene ring [79.56 (8) and 43.52 (8)° in the other cation]. In the crystal structure, N—H...O, O—H...O and C—H...O hydrogen bonds link the ions and water molecules, forming a three-dimensional network.
4-(Ammoniomethyl)pyridinium dichloride  [cached]
Meher El Glaoui,Riadh Kefi,Olfa Amri,Erwann Jeanneau
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808034405
Abstract: The title compound, C6H10N22+·2Cl , contains a network of 4-(ammoniomethyl)pyridinium cations and chloride anions which are interconnected by N—H...Cl hydrogen bonds. The crystal packing is also influenced by intermolecular π–π stacking interactions between identical antiparallel organic cations with a face-to-face distance of ca 3.52 .
4-[(2,4-Dihydroxybenzylidene)ammonio]benzenesulfonate trihydrate  [cached]
Chin Sing Yeap,Madhukar Hemamalini,Hoong-Kun Fun
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810004526
Abstract: The title Schiff base compound, C13H11NO5S·3H2O, formed from sulfanilic acid and 2,4-dihydroxybenzaldehyde, crystallized out as a zwitterion with the N atom protonated. The asymmetric unit consists of one 4-[(2,4-dihydroxybenzylidene)ammonio]benzenesulfonate and three water molecules. The zwitterion exists in an E configuration with respect to the central C=N double bond. The two benzene rings of the molecule are oriented at a dihedral angle of 27.33 (8)°. An intramolecular N–H...O hydrogen bond stabilizes the molecular structure. In the crystal, the zwitterions are linked into chains along [101] by intermolecular O—H...O and N—H...O hydrogen bonds. The three water molecules link these chains into a three-dimensional framework by additional intermolecular O—H...O hydrogen bonds. A π...π interaction [3.5485 (9) ] further stabilizes the crystal structure.
(E)-4-[4-(Diethylamino)benzylideneammonio]benzenesulfonate  [cached]
Pumsak Ruanwas,Suchada Chantrapromma,Hoong-Kun Fun
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812026402
Abstract: The title compound, C17H20N2O3S, synthesised from sulfanilic acid and 4-diethylaminobenzaldehyde, crystallized out as a zwitterion with the central N atom protonated. The zwitterion exists in an E conformation with respect to the C=N double bond. The dihedral angle between the benzene rings is 37.57 (5)°. In the crystal, the zwitterions are linked into a tape along the a axis by N—H...O hydrogen bonds. The crystal structure is further stabilized by weak C—H...O interactions and π–π interactions with a centroid–centroid distance of 3.8541 (6) . An O...O [2.8498 (11) ] short contact is present.
Synthesis, Characterization, and Crystal Structure of Pyridinium Tetrakis{1-trifluoromethyl-3-(1′-pyreno)-1,3-propanedionato}lanthanate(III) Complex  [PDF]
Tetsuji Moriguchi,Kenji Yoza,Akihiko Tsuge
Journal of Crystallography , 2014, DOI: 10.1155/2014/271238
Abstract: The reaction of 1-trifluoromethyl-3-(1′-pyreno)-1,3-propanedione with lanthanum(III) trichloride in the presence of pyridine leads to halide ligand exchange, yielding a novel pyridinium tetrakis{1-trifluoromethyl-3-(1′-pyreno)-1,3-propanedionato}lanthanate(III) complex with four polycyclic aromatic hydrocarbon moieties. This reaction easily proceeds under mild conditions (25°C, 24?h) producing the complex in a 90% isolated yield. The complex was characterized by infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and positive fast atom bombardment mass spectrometry, and its precise structure was determined by single crystal X-ray diffraction. Ultraviolet-visible spectroscopy, fluorescence spectroscopy, and X-ray analysis demonstrated that the four pyrene moieties were independently oriented. 1. Introduction In recent years, lanthanide(III) complexes with β-diketonato ligands consisting of various aromatic components have attracted numerous researchers [1]. These compounds represent well-known electronic and luminescent materials with numerous applications in material chemistry [2–4]. In addition, polycyclic aromatic hydrocarbons (PAHs), such as pyrene and perirene, have been highlighted by numerous researchers because of their electronic and luminescent properties [5–9]. From our recent work, the structures of the octadentate lanthanide(III) complex derived by X-ray analysis were reported to be unexpectedly cone-like [10]. The present study focuses on the synthesis and investigation of the structural properties of the novel octacoordinate lanthanum(III) complex with four bidentate β-diketonato ligands having four PAH (pyrene) moieties and one pyridinium ion as a counter cation. We also confirmed the exact structure of the octadentate lanthanide coordination complex having highly aggregated PAHs by X-ray analysis. 2. Materials and Methods All the reagents and solvents were obtained from commercial sources and were used as received. Infrared spectra were recorded on a HITACHI FT-IR 410X instrument using the KBr method. Proton nuclear magnetic resonance (1H-NMR) spectra were obtained on a Bruker 400?MHz Avance400S spectrometer at 293?K in chloroform-d3 using tetramethylsilane (Me4Si) as an internal reference. Positive fast atom bombardment mass spectrometry (pos. FAB-MS) spectra were obtained on a Noppon Densi JEOL JMS-SX102A spectrometer using nitrobenzylalcohol (NBA) as the matrix and dichloromethane (DCM) as the solvent. This instrument was operated in the positive ion mode using an m/z range of 100–2000. Elemental analysis was
4-(4-Nitrobenzenesulfonamido)pyridinium nitrate  [cached]
Liang-Bin Hu,Yu-Xiang Ma,Chang-Zhong Liu,Ji-Guo Yang
Acta Crystallographica Section E , 2008, DOI: 10.1107/s160053680803883x
Abstract: A short C—N distance [1.394 (2) ] in the title compound, C11H10N3O4S+·NO3 , is indicative of some conjugation of the sulfonamide π electrons with those of the pyridinium ring. The crystal structure is stabilized by N—H...O hydrogen bonds.
4-(Dimethylamino)pyridinium tetrachloridoferrate(III)  [cached]
Amina Khadri,Rafika Bouchene,Sofiane Bouacida,Hocine Merazig
Acta Crystallographica Section E , 2013, DOI: 10.1107/s160053681300603x
Abstract: The title salt, (C7H11N2)[FeCl4], consists of one essentially planar (the r.m.s. deviation for all non-H atoms being 0.004 ) 4-(dimethylamino)pyridinium cation and a tetrahedral tetrachloridoferrate(III) anion. The cations and anions are arranged in layers parallel to (010). Besides electrostatic interactions, the crystal packing features N—H...Cl and C—H...Cl hydrogen bonds between cations and anions, forming a three-dimensional network.
Bis[4-(2-nitrobenzenesulfonamido)pyridinium] hexafluorosilicate  [cached]
Ai-Rong Wang
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808038191
Abstract: In the title compound, 2C11H10N3O4S+·SiF62 , the short C—N distance [1.386 (2) ] is indicative of a slight conjugation of N with the π electrons of the pyridinium ring, and with those of the sulfonyl group. The dihedral angle between the benzene and pyridinium rings is 77.48 (7)°. The crystal structure is stabilized by N—H...F and C—H...F hydrogen bonds. The Si atom of the anion lies on a special position.
Antibacterial Activity of Salicylanilide 4-(Trifluoromethyl)-benzoates  [PDF]
Martin Krátky,Jarmila Vin?ová,Eva Novotná,Jana Mandíková,Franti?ek Trejtnar,Ji?ina Stola?íková
Molecules , 2013, DOI: 10.3390/molecules18043674
Abstract: The development of novel antimicrobial agents represents a timely research topic. Eighteen salicylanilide 4-(trifluoromethyl)benzoates were evaluated against Mycobacterium tuberculosis, M. avium and M. kansasii, eight bacterial strains including methicillin-resistant Staphylococcus aureus (MRSA) and for the inhibition of mycobacterial isocitrate lyase. Some compounds were further screened against drug-resistant M. tuberculosis and for their cytotoxicity. Minimum inhibitory concentrations (MICs) for all mycobacterial strains were within 0.5–32 μmol/L, with 4-chloro-2-[4-(trifluoromethyl)phenylcarbamoyl]phenyl 4-(trifluoromethyl)benzoate superiority. Gram-positive bacteria including MRSA were inhibited with MICs 3 0.49 μmol/L, while Gram-negative ones were much less susceptible. Salicylanilide 4-(trifluoromethyl)benzoates showed significant antibacterial properties, for many strains being comparable to standard drugs (isoniazid, benzylpenicillin) with no cross-resistance. All esters showed mild inhibition of mycobacterial isocitrate lyase and four compounds were comparable to 3-nitropropionic acid without a direct correlation between in vitro MICs and enzyme inhibition.
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