Displaying publications 21 - 40 of 692 in total

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  1. Burrett S, Taylor DK, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2014 Jul 1;70(Pt 7):o776-7.
    PMID: 25161564 DOI: 10.1107/S1600536814013543
    Four independent mol-ecules (A-D) comprise the asymmetric unit of the title compound, C15H26O2, which differ only in the relative orientations of the terminal -C(Me)2OH groups [e.g. the range of Cmethyl-ene-Cmethine-Cquaternary-Ohy-droxy torsion angles is 52.7 (7)-57.1 (6)°, where the Cmethyl-ene atom is bound to an epoxide C atom]. The five-membered rings adopt envelope conformations, with the methyl-ene C atom adjacent to the methine C atom being the flap atom in each case. In each mol-ecule, the conformation of the seven-membered ring is a half-chair, with the Cmethyl-ene-Cmethine bond, flanked by methyl-ene C atoms, being the back of the chair. Supra-molecular helical chains along the b axis are found in the crystal packing, sustained by hy-droxy-epoxide O-H⋯O hydrogen bonding. Mol-ecules of A self-associate into a chain as do those of D. A third independent chain comprising B and C mol-ecules is also formed. The studied crystal is a pseudo-merohedral twin (minor component ca 21%).
  2. Adam F, Ameram N, Eltayeb NE
    PMID: 25249927 DOI: 10.1107/S1600536814016377
    In the title compound, C16H17N3OS, the dihedral angle between the planes of the benzene and pyridine rings is 71.33 (15)°. An intra-molecular N-H⋯O hydrogen bond is present. In the crystal, weak aromatic C-H⋯O hydrogen bonds link the mol-ecules into chains extending along a.
  3. Edison B, Balasubramani K, Thanigaimani K, Khalib NC, Arshad S, Razak IA
    Acta Crystallogr Sect E Struct Rep Online, 2014 Aug 1;70(Pt 8):o857-8.
    PMID: 25249908 DOI: 10.1107/S1600536814015220
    In the title mol-ecular salt, C4H6ClN4 (+)·C5H7O4 (-), the cation is essentially planar, with a maximum deviation of 0.037 (1) Å for all non-H atoms. The anions are self-assembled through O-H⋯O hydrogen bonds, forming a supra-molecular zigzag chain with graph-set notation C(8). In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds with an R 2 (2)(8) ring motif. This motif further self-organizes through N-H⋯O and O-H⋯O hydrogen bonds, generating an array of six hydrogen bonds, the rings having graph-set notation R 3 (2)(8), R 2 (2)(8), R 4 (2)(8), R 2 (2)(8) and R 3 (2)(8). In addition, another type of R 2 (2)(8) motif is formed by inversion-related pyrimidinium cations via N-H⋯N hydrogen bonds, forming a two-dimensional network parallel to (101).
  4. Akhmad Aznan AM, Abdullah Z, Tiekink ER
    PMID: 25161500 DOI: 10.1107/S1600536814011532
    The 1:1 co-crystallization of 1,4-di-aza-bicyclo-[2.2.2]octane (DABCO) with 4-nitro-benzoic acid in ethanol-water (3/1) gave the salt dihydrate C6H13N2 (+)·C7H4NO4 (-)·2H2O, (1), whereas from methanol, the salt C6H14N2 (2+)·2C7H4NO4 (-), (2), was isolated. In (1), the cation and anion are linked by a strong N-H⋯O hydrogen bond, and the carboxyl-ate anion is close to planar [dihedral angle between terminal residues = 6.83 (9)°]. In (2), a three-ion aggregate is assembled by two N-H⋯O hydrogen bonds, and the carboxyl-ate anions are again close to planar [dihedral angles between terminal residues = 1.7 (3) and 5.9 (3)°]. Through the inter-vention of solvent water mol-ecules, which self-assemble into helical supra-molecular chains along the b axis, the three-dimensional architecture in (1) is stabilized by water-DABCO O-H⋯N and water-carboxyl-ate O-H⋯O hydrogen bonds, with additional stability afforded by C-H⋯O inter-actions. The global crystal structure comprises alternating layers of water mol-ecules and ion pairs stacked along the c axis. In the crystal of (2), the three-ion aggregates are assembled into a three-dimensional architecture by a large number of methyl-ene-carboxyl-ate/nitro C-H⋯O inter-actions as well as π-π contacts between inversion-related benzene rings [inter-centroid distances = 3.5644 (16) and 3.6527 (16) Å]. The cations and anions assemble into alternating layers along the c axis.
  5. Chantrapromma S, Jeerapong C, Phupong W, Quah CK, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 Apr 1;70(Pt 4):o408-9.
    PMID: 24826124 DOI: 10.1107/S1600536814004632
    The title compound, C20H28O3, known as 'trichodermaerin' [systematic name: (4E)-4,9,15,16,16-penta-methyl-6-oxa-tetra-cyclo-[10.3.1.0(1,10).0(5,9)]hexa-dec-4-ene-7,13-dione], is a diterpene lactone which was isolated from Trichoderma asperellum. The structure has a tetra-cycic 6-5-7-5 ring system, with the cyclo-hexa-none ring adopting a twisted half-chair conformation and the cyclo-pentane ring adopting a half-chair conformation, whereas the cyclo-heptene and tetra-hydro-furan-anone rings are in chair and envelope (with the methyl-substituted C atom as the flap) conformations, respectively. The three-dimensional architecture is stabilized by C-H⋯O inter-actions.
  6. Arman HD, Kaulgud T, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2014 Apr 1;70(Pt 4):o402-3.
    PMID: 24826120 DOI: 10.1107/S1600536814004838
    The sulfa-thia-zole mol-ecule in the title 1:1 co-crystal, C9H9N3O2S2·C18H12N6, adopts an approximate L-shape [dihedral angle between the five- and six-membered rings = 86.20 (9)°] and features an intra-molecular hypervalent S⋯O inter-action [2.8666 (15) Å]. Overall, the triazine mol-ecule has the shape of a disk as the pendant pyridine rings are relatively close to coplanar with the central ring [dihedral angles = 18.35 (9), 6.12 (9) and 4.67 (9)°]. In the crystal packing, a linear supra-molecular chain aligned along [01-1] is formed as a result of amino-pyridyl N-H⋯N hydrogen bonding with syn-disposed pyridyl mol-ecules of one triazine, and amine-pyridyl N-H⋯N hydrogen bonding with the third pydridyl ring of a second triazine mol-ecule. A three-dimensional architecture arises as the chains are connected by C-H⋯O inter-actions.
  7. Chantrapromma S, Kaewmanee N, Boonnak N, Quah CK, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 Apr 1;70(Pt 4):o395-6.
    PMID: 24826116 DOI: 10.1107/S1600536814004577
    The asymmetric unit of the title hydrated salt, C22H25N2 (+)·C6H4ClO3S(-)·H2O, comprises two 2-[4-(di-ethyl-amino)-styr-yl]-1-methyl-quinolin-1-ium cations, two 4-chloro-benzene-sul-fon-ate anions and two solvent water mol-ecules. One ethyl group of both cations displays disorder over two positions in a 0.659 (2):0.341 (2) ratio in one mol-ecule and in a 0.501 (2):0.499 (2) ratio in the other. The sulfonate group of one anion is also disordered over two positions in a 0.893 (7):0.107 (7) ratio. The dihedral angle between the mean plane of the quinolinium ring system and that of benzene ring is 10.57 (18)° in one cation and 14.4 (2)° in the other. In the crystal, cations, anions and water mol-ecules are linked into chains along the [010] direction by O-H⋯Osulfonate hydrogen bonds, together with weak C-H⋯Osulfonate and C-H⋯Cl inter-actions. The cations are stacked by π-π inter-actions, with centroid-centroid distances in the range 3.675 (2)-4.162 (3) Å.
  8. Vaneesa Nagalingam S, Wong Pik Ching J, Khaled Bin Break M, Tahir MI, Khoo TJ
    Acta Crystallogr Sect E Struct Rep Online, 2013 Dec 1;69(Pt 12):o1799-800.
    PMID: 24860292 DOI: 10.1107/S1600536813031036
    The title compound, C33H42O4 [systematic name: (1S,5S,7R)-3-benzoyl-4-hy-droxy-8,8-dimethyl-1,5,7-tris-(3-methyl-but-2--enyl)bi-cyclo-[3.3.1]nona-3-ene-2,9-dione], has a central bi-cyclo-[3.3.1]nonane-2,4,9-trione surrounded by tetra-prenyl-ated and benzoyl groups. The compound was recrystallized several times in methanol using both a slow evaporation method and with a crystal-seeding technique. This subsequently produced diffraction-quality crystals which crystallize in the ortho-rhom-bic space group P212121, in contrast to a previous report of a structure determination in the Pna21 space group [McCandlish et al. (1976 ▶). Acta Cryst. B32, 1793-1801]. The title compound has a melting point of 365-366 K, and a specific rotation [α](20) value of +51.94°. A strong intra-molecular O-H⋯O hydrogen bond is noted. In the crystal, mol-ecules are assembled in the ab plane by weak C-H⋯O inter-actions.
  9. Rahman ML, Srinivasa HT, Mashitah MY, Kwong HC, Quah CK
    PMID: 24860410 DOI: 10.1107/S160053681400909X
    In the title compound, C24H23NO2, a whole mol-ecule is disordered over two sets of sites with occupancies in a ratio of 0.692 (6):0.308 (6). In the major disorder component, the naphthalene ring system forms a dihedral angle of 68.6 (5)° with the benzene ring. The corresponding angle in the minor component is 81.6 (10)°. In the crystal, mol-ecules are linked into chains propagating along the b-axis direction via weak C-H⋯O hydrogen bonds. The crystal packing is further consolidated by weak C-H⋯π inter-actions.
  10. Yamin BM, Hizam SM, Yusoff SF, Hasbullah SA
    PMID: 24860396 DOI: 10.1107/S1600536814008952
    The title compound, C13H18N2O2S, adopts a cis conformation between the methyl-benzoyl and thiono groups across their thio-urea C-N bond. However, the methyl-benzoyl group and N2CS thio-urea moiety are twisted by 15.03 (3)°. In the molecule there is an N-H⋯O hydrogen bond. In the crystal, mol-ecules are linked by O-H⋯O inter-actions, generating chains extending along the c-axis direction.
  11. Ruanwas P, Chantrapromma S, Ghabbour HA, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 May 1;70(Pt 5):o589-90.
    PMID: 24860388 DOI: 10.1107/S1600536814008356
    There are two crystallograpically independent mol-ecules in the asymmetric unit of the title bis-chalcone derivative, C25H32N2O. Both mol-ecules are twisted with a dihedral angle between the two substituted benzene rings of 11.19 (16)° in one mol-ecule and 14.40 (15)° in the other. The central penta-1,4-dien-3-one fragments make dihedral angles of 8.49 (17) and 4.26 (17)° with the two adjacent benzene rings in one mol-ecule, whereas the corresponding values are 8.42 (16) and 6.18 (16)° in the other. In the crystal, mol-ecules are arranged into chains along the c-axis direction. Adjacent chains are inter-linked by weak inter-molecular C-H⋯O inter-actions. The crystal is further stabilized by C-H⋯π inter-actions.
  12. Awang NW, Hasbullah SA, Yusoff SF, Yamin BM
    PMID: 24860375 DOI: 10.1107/S1600536814008174
    In the title compound, C12H15FN2O2S, the mol-ecule adopts a cis configuration of the fluoro-benzoyl group with respect to the thiono group about their C-N bond. The dihedral angle between the fluoro-benzoyl group and the thio-urea N2CS fragment is 69.60 (11)°. An intra-molecular N-H⋯O hydrogen bond occurs. In the crystal, mol-ecules form chains along the b-axis direction via O-H⋯S and C-H⋯O hydrogen bonds.
  13. Chantrapromma S, Chanawanno K, Boonnak N, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 May 1;70(Pt 5):o510-1.
    PMID: 24860326 DOI: 10.1107/S160053681400645X
    The asymmetric unit of the title salt, C36H32N2 (2+)·2C6H4ClO3S(-), consists of one anion and one half-cation, the other half being generated by inversion symmetry. The dihedral angle between the pyridinium ring and the napthalene ring system in the asymmetric unit is 42.86 (6)°. In the crystal, cations and anions are linked by weak C-H⋯O inter-actions into chains along [010]. Adjacent chains are further arranged in an anti-parallel manner into sheets parallel to the bc plane. π-π inter-actions are observed involving the cations, with centroid-centroid distances of 3.7664 (8) and 3.8553 (8) Å.
  14. Chantrapromma S, Boonnak N, Horkaew J, Quah CK, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 Feb 1;70(Pt 2):o150-1.
    PMID: 24764873 DOI: 10.1107/S1600536814000531
    The title compound crystallizes as a hemihydrate, C18H20N2O5·0.5H2O. The mol-ecule exists in an E conformation with respect to the C=N imine bond. The 4-meth-oxy-phenyl unit is disordered over two sets of sites with a refined occupancy ratio of 0.54 (2):0.46 (2). The dihedral angles between the benzene rings are 29.20 (9) and 26.59 (9)°, respectively, for the major and minor components of the 4-meth-oxy-substituted ring. All meth-oxy substituents lie close to the plane of the attached benzene rings [the Cmeth-yl-O-C-C torsion angles range from -4.0 (12) to 3.9 (2)°]. In the crystal, the components are linked into chains propagating along [001] via N-H⋯O and O-H⋯O hydrogen bonds and weak C-H⋯O inter-actions.
  15. Yamin BM, Kamalulazmy NA, Hassan NI
    PMID: 24764859 DOI: 10.1107/S1600536814000245
    The complete title molecule, C23H19N3O2, is generated by a twofold axis passing through the central ring. The two oxymethyl-benzo-nitrile arms are attached at the meta positions of the central pyridine ring. The dihedral angle between the pyridine ring and benzene ring of both arms is 84.55 (6)° while the benzene rings make a dihedral angle of 46.07 (7)°. In the crystal, weak C-H⋯π inter-actions link the molecules sheets parallel to the ac plane.
  16. Taha M, Shah SA, Sultan S, Ismail NH, Yousuf S
    Acta Crystallogr Sect E Struct Rep Online, 2014 Feb 01;70(Pt 2):o131.
    PMID: 24764858 DOI: 10.1107/S1600536813034636
    The title phenyl-hydrazine derivative, C16H16N2O4, has a crystallographically imposed centre of symmetry. Except for the methyl group, all non-H atoms are almost coplanar (r.m.s. deviation = 0.0095 Å). Intra-molecular O-H⋯N hydrogen bonds are observed, generating S(6) graph-set ring motifs.
  17. Hariono M, Wahab HA, Tan ML, Rosli MM, Razak IA
    PMID: 24764997 DOI: 10.1107/S1600536814001986
    In the title compound, C19H17N5S, the dihedral angles between the purine ring system (r.m.s. deviation = 0.009 Å) and the S-bound and methyl-ene-bound phenyl rings are 74.67 (8) and 71.28 (7)°, respectively. In the crystal, inversion dimers linked by pairs of N-H⋯N hydrogen bonds generate R 2 (2)(8) loops. C-H⋯N inter-actions link the dimers into (100) sheets.
  18. Bagabas AA, Aboud MF, Shemsi AM, Addurihem ES, Al-Othman ZA, Chidan Kumar CS, et al.
    Acta Crystallogr Sect E Struct Rep Online, 2014 Mar 1;70(Pt 3):o253-4.
    PMID: 24764971 DOI: 10.1107/S1600536814002244
    In the title salt, C6H14N(+)·NO3 (-), the cyclo-hexyl ring adopts a chair conformation. The ammonium group occupies an equatorial position and the crystal struture is stabilized by inter-molecular N-H⋯O hydrogen-bonding inter-actions, resulting in a three-dimensional network.
  19. Sinha B, Dey GC, Sarkar B, Roy A, Ng SW, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2014 Mar 1;70(Pt 3):m112-3.
    PMID: 24764942 DOI: 10.1107/S1600536814004280
    The title complex, [Cu{μ3-O2CC6H3(NO2)2-3,5}(μ-OH)] n , features zigzag chains in which successive pairs of Cu(II) atoms are connected by OH bridges and bidentate carboxyl-ate ligands, leading to six-membered Cu(O)(OCO)Cu rings. The zigzag chains are connected into a three-dimensional architecture by Cu-O(nitro) bonds. The coordination geometry of the Cu(II) atom is square-pyramidal, with the axial position occupied by the nitro O atom, which forms the longer Cu-O bond. Bifurcated hy-droxy-nitro O-H⋯O hydrogen bonds contribute to the stability of the crystal structure.
  20. Chantrapromma S, Ruanwas P, Boonnak N, Chidan Kumar CS, Fun HK
    Acta Crystallogr Sect E Struct Rep Online, 2014 Feb 1;70(Pt 2):o188-9.
    PMID: 24764900 DOI: 10.1107/S1600536814001238
    Mol-ecules of the title compound, C16H16N4O7, are not planar with a dihedral angle of 5.50 (11)° between the substituted benzene rings. The two meta-meth-oxy groups of the 3,4,5-tri-meth-oxy-benzene moiety lie in the plane of the attached ring [Cmeth-yl-O-C-C torsion angles -0.1 (4)° and -3.7 (3)°] while the para-meth-oxy substituent lies out of the plane [Cmeth-yl-O-C-C, -86.0 (3)°]. An intra-molecular N-H⋯O hydrogen bond involving the 2-nitro substituent generates an S(6) ring motif. In the crystal structure, mol-ecules are linked by weak C-H⋯O inter-actions into screw chains, that are arranged into a sheet parallel to the bc plane. These sheets are connected by π-π stacking inter-actions between the nitro and meth-oxy substituted aromatic rings with a centroid-centroid separation of 3.9420 (13) Å. C-H⋯π contacts further stabilize the two-dimensional network.
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