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6-[(4-Hydroxyphenyl)diazenyl]-1,10-phenanthrolin-1-ium chloride monohydrate
Akram Hazeen,Yan Zhang,Minchong Mao,Kraig A. Wheeler
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811044941
Abstract: In the cation of the title molecular salt, C18H13N4O+·Cl ·H2O, the dihedral angle between the mean planes of the 1,10-phenanthroline system and the phenol ring is 14.40 (19)°. The crystal packing is stabilized by O—H...O hydrogen bonds, weak N—H...Cl and O—H...Cl intermolecular interactions and π—π stacking interactions [centroid–centroid distance = 3.6944 (13) and 3.9702 (12) ]
Aquabis(2-methyl-4-oxopyrido[1,2-a]pyrimidin-9-olato)zinc(II) monohydrate  [cached]
Yu-Feng Wei,Zhong-Shu Li,Huai-Hong Zhang,Yi-Hong Wang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536808039615
Abstract: The crystal structure of the title compound, [Zn(C9H7N2O2)2(H2O)]·H2O, involves discrete mononuclear complex molecules. The special positions on the rotation twofold axis are occupied by ZnII and O atoms of the coordinated and uncoordinated water molecules. The coordination around the ZnII atom can be described as transitional from trigonal-bipyramidal to square-pyramidal. The two chelating 2-methyl-4-oxopyrido[1,2-a]pyrimidin-9-olate ligands and the coordinated water molecule form the Zn coordination. O—H...O hydrogen bonds between the coordinated water molecule and the ligand and between the uncoordinated water molecule and the ligand dominate the crystal packing.
2-Oxo-1,2-dihydropyrimidin-3-ium di-μ-chlorido-bis{dichloridobis[pyrimidin-2(1H)-one-κN3]cuprate(II)} dihydrate
Mukhtar A. Kurawa,Christopher J. Adams,A. Guy Orpen
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808017455
Abstract: The asymmetric unit of the title compound, (C4H5N2O)2[Cu2Cl6(C4H4N2O)2]·2H2O, consists of one cation, one half of a centrosymmetric dianion and one water molecule. The centrosymmetric dianion formed by dimerization in the crystal structure has neutral pyrimidin-2-one ligands coordinated to each copper(II) centre through Cu—N bonds. The Cu atoms each have a distorted trigonal bipyramidal geometry, with the N atom of the pyrimidin-2-one ligand in an axial position, and dimerize by sharing two equatorial Cl atoms. N—H...Cl, O—H...Cl and N—H...O hydrogen bonds connect the anions, cations and water molecules, forming a three-dimensional network.
Bis(7-amino-1,2,4-triazolo[1,5-a]pyrimidin-4-ium) bis(oxalato-κ2O1,O2)cuprate(II) dihydrate
Ana B. Caballero,Óscar Castillo,Antonio Rodríguez-Diéguez,Juan M. Salas
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811040724
Abstract: The structure of the title ionic compound, (C5H6N5)2[Cu(C2O4)2]·2H2O, consists of a centrosymmetric copper(II) oxalate dianion, two monoprotonated molecules of the adenine analog 7-amino-1,2,4-triazolo[1,5-a]pyrimidine (7atp) and two water molecules of crystallization. The CuII ion, located on an inversion center, exhibits a sligthly distorted square-planar coordination geometry, in which two oxalate anions bind in a bidentate fashion. The triazolopyrimidine ligand is protonated at the N atom in position 4, instead of its most basic N atom in position 3. This fact may be explained by the network stability, which is provided through the formation of a two-dimensional wave-like network parallel to (50overline1) by N—H...O, O—H...N and O—H...O hydrogen bonds. These nets are further connected via C—H...O interactions.
Caffeinium bisulfate monohydrate  [cached]
C. Vincent Jerin,S. Athimoolam
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811031540
Abstract: In the title compound (systematic name: 1,3,7-trimethyl-2,6-dioxo-7H-purin-9-ium hydrogen sulfate monohydrate), C8H11N4O2+·HSO4 ·H2O, the crystal packing is stabilized through N—H...O and O—H...O hydrogen bonds.
1-{[Dimethyl(phenyl)silyl]methyl}-3-(2-phenylethyl)-1H-benzimidazol-3-ium bromide monohydrate  [cached]
Mehmet Akkurt,Hasan Küçükbay,Nihat Şireci,Orhan Büyükgüngör
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812034915
Abstract: The title compound, C24H27N2Si+·Br ·H2O, was synthesized from 1-(dimethylphenylsilylmethyl)-1H-benzimidazole and (2-bromoethyl)benzene in dimethylformamide. The benzimidazole ring system is nearly planar, with a maximum deviation of 0.015 (5) , and forms dihedral angles of 73.0 (3) and 39.6 (2)°, with the phenyl rings. In the crystal, molecules are linked by O—H...Br, C—H...Br and C—H...O hydrogen bonds. In addition, the structure features π–π stacking interactions, with a face-to-face separation of 3.644 (3) between parallel benzimidazole ring systems.
1-(5-Carboxypentyl)-2,3,3-trimethyl-3H-indol-1-ium bromide monohydrate
Angela Winstead,Krystal Hart,Yousef M. Hijji,Jerry P. Jasinski
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536809049204
Abstract: In the title compound, C17H24NO2+·Br ·H2O, the pentyl group chain in the cation extends nearly perpendicular [N—C—C—C = 64.4 (3)°] to the mean plane of the indole ring with the carboxyl end group twisted such that the dihedral angle between the mean planes of the indole and carboxy groups measures 43.2 (4)°. Both ions in the salt form intermolecular hydrogen bonds (O—H...Br and O—H...O) with the water molecule. As a result of the Br...H—O—H...Br interactions, a zigzag chain is formed in the c-axis direction. The crystal packing is influenced by the collective action of the O—H...O and O—H...Br intermolecular interactions as well as π–π stacking intermolecular interactions between adjacent benzyl rings of the indole group [centroid–centroid distance = 3.721 (13) ] and intermolecular C—H...π interactions between a methyl hydrogen and the benzyl ring of the indole group. The O—H...Br interactions form a distorted tetrahedral array about the central Br atom. A MOPAC AM1 calculation provides support to these observations.
Bosentan monohydrate  [cached]
Manpreet Kaur,Jerry P. Jasinski,Amanda C. Keeley,H. S. Yathirajan
Acta Crystallographica Section E , 2013, DOI: 10.1107/s1600536812048969
Abstract: In the title compound, C27H29N5O6S·H2O {systematic name: 4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-(pyrimidin-2-yl)pyrimidin-4-yl]benzene-1-sulfonamide monohydrate], the dihedral angle between the mean planes of the pyrimidine rings is 27.0 (1)°. The dihedral angle between the mean planes of the benzene rings is 47.7 (8)°, forming a U-shaped channel around the chain of twisted pyrimidine rings. The crystal packing is stabilized by O—H...O, O—H...N and N—H...O hydrogen bonds with a single water molecule, and weak O—H...N intermolecular interactions between the hydroxy group and one of the pyrimidine rings producing an two-dimensional supramolecular array in the bc plane. The title compound studied was a merohedral twin with the major component being approximately 57%.
(E)-1,1′-Bis[(E)-but-2-enyl]-3,3′-(propane-1,3-diyl)bis(1H-benzimidazol-3-ium) dibromide monohydrate  [cached]
Mehmet Akkurt,Sema ?ztürk Y?ld?r?m,Nihat ?ireci,Hasan Kü?ükbay
Acta Crystallographica Section E , 2008, DOI: 10.1107/s160053680803095x
Abstract: The title compound, C25H30N42+·2Br ·H2O, was synthesized from 1,1′-propylenedibenzimidazole and (E)-1-bromobut-2-ene in dimethylformamide solution. The two benzimidazole ring systems are essentially planar, with maximum deviations of 0.011 (4) and 0.023 (3) . The dihedral angle between these two ring systems is 25.87 (15)°. The crystal structure is stabilized by intermolecular O—H...Br and C—H...Br hydrogen-bonding interactions. Atmospheric water was incorporated into the crystal structure.
A Facile One-pot Synthesis of 1-Arylpyrazolo[3,4-d]Pyrimidin- 4-ones  [PDF]
Xiaohong Zhang,Qiulian Lin,Ping Zhong
Molecules , 2010, DOI: 10.3390/molecules15053079
Abstract: One pot synthesis of 1-arylpyrazolo[3,4-d]pyrimidin-4-ones by the reaction of 5-amino-N-substituted-1H-pyrazole-4-carbonitrile with different lower aliphatic acids in the presence of POCl3has been developed. The structures of all the title compounds have been confirmed by IR, 1H-NMR, 13C-NMR, and elemental analyses. Moreover, the structures of one of these compounds, 2c, was confirmed by single-crystal X-ray diffraction.
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