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In the title compound, [Re3([mu]-H)3(C25H22P2)(CO)10]·CH2Cl2, the three Re atoms form a triangle bearing ten terminal carbonyl groups and three edge-bridging hydrides. The bis­(diphenyl­phosphan­yl)methane ligand bridges two Re atoms. Neglecting the Re-Re inter­actions, each Re atom is in a slightly distorted octa­hedral coordination environment. The dichloro­methane solvent mol­ecule is disordered over two sets of sites with fixed occupancies of 0.6 and 0.4.

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The title compound, C9H12N2OS, was obtained unexpectedly in a multicomponent reaction of an equimolar ratio of phenyl isothio­cyanate, malononitrile and amino­ethanol. The -C(H2)-N(H)-(C=S)-N(H)- methyl­thio­urea-methane group is almost normal to the phenyl ring, with a dihedral angle of 71.13 (9)°. The N-C-C-O torsion angle is 72.8 (2)°. In the crystal, mol­ecules are connected by N-H...O, O-H...S and N-H...O hydrogen bonds, forming a three-dimensional network.

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In the title compound, C10H8N2S, the 2-amino­benzothia­zole and propyne groups are not coplanar [dihedral angle = 71.51 (1)°]. The crystal structure is stabilized by strong inter­molecular N-H...N hydrogen bonds and C-H...C, C-H...[pi] and F-type aromatic-aromatic [centroid-centroid distance = 3.7826 (12) Å] inter­actions are also observed.

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In the title compound, C10H9N3, the benzimidazol-2-amine and CH2-C[triple bond]CH units are not coplanar, with a dihedral angle of 60.36° between their mean planes. The crystal structure is stabilized by inter­molecular N-H...N hydrogen bonding and [pi]-[pi] inter­actions [centroid-centroid distances 3.677 (1) and 3.580 (1) Å], assembling the mol­ecules into a supra­molecular structure with a three-dimensional network.

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In the title compound, C10H8N2S, the 2-amino­benzothia­zole and propyne groups are not coplanar [dihedral angle = 71.51 (1)°]. The crystal structure is stabilized by strong inter­molecular N-H...N hydrogen bonds and C-H...C, C-H...[pi] and F-type aromatic-aromatic [centroid-centroid distance = 3.7826 (12) Å] inter­actions are also observed.

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The design, implementation and performance evaluation of the X-ray imaging beamline (BL-4) is reported. Some of the first experiments on propagation-based phase contrast imaging and micro-tomography are also reported.

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In-house-developed flame-retardant rigid polyurethane foam was exposed to gamma irradiation doses in the 0–20 kGy range and synchrotron X-ray computed tomography was employed for the analysis of radiation-induced morphological variations in their cellular microstructure.

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The crystal structure of pyroglutamate (pG) bound PCP I enzyme reveals the mechanism of its pG specificity. The residues of a conserved active-site loop interact with pG via phenylalanine stacking interactions and hydrogen bonds.


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The title compound, C26H24Cl2N2, crystallizes with two independent mol­ecules (1 and 2) in the asymmetric unit. In mol­ecule 1, the two phenyl and 2,6-di­chloro­phenyl rings are inclined to the imidazole ring at angles of 74.12 (14), 26.13 (14) and 67.30 (14)°, respectively. In mol­ecule 2, due to the different mol­ecular environment in the crystal, the corresponding angles are different, viz. 71.72 (15), 16.14 (15) and 80.41 (15)°, respectively. In the crystal, mol­ecules 1 and 2 are linked by C-H...Cl inter­actions, and inversion-related 2 mol­ecules are linked by C-H...[pi] inter­actions. There are no other significant inter­molecular inter­actions present.

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The CuI atom in the mol­ecular structure of the title compound exhibits a distorted tetra­hedral coordination sphere, defined by two N atoms of the chelating ligand, one N atom of the aceto­nitrile ligand and one iodide ligand.

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The asymmetric unit of the title compound contains two independent mol­ecules. In the crystal, C—H...O hydrogen bonds link the mol­ecules into chains along [100].

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The structure of the title compound (systematic name: 3,5-dihydr­oxy-2-isobutyryl-4,6,6-tris­(3-methyl-but-2-en­yl)cyclo­hexa-2,4-dienone), C25H36O4, is of inter­est with respect to its biological activity. The structure displays O—H...O=C intra- and inter­molecular inter­actions, with O...O distances of 2.398 (2) and 2.6846 (19) Å, respectively.

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The title compound, C46H40N4O2·0.33C6H12, was obtained unintentionally as a product of an attempted synthesis of a cadmium(II) complex of the [2,6-{PhSe(CH2)2N=CPh}2C6H2(4-Me)(OH)] ligand. The full tetra­imino­diphenol macrocyclic ligand is generated by the application of an inversion centre. The macrocyclic ligand features strong intra­molecular O-H...N hydrogen bonds. The dihedral angles formed between the phenyl ring incorporated within the macrocycle and the peripheral phenyl rings are 82.99 (8) and 88.20 (8)°. The cyclo­hexane solvent mol­ecule lies about a site of \overline{3} symmetry. Other solvent within the lattice was disordered and was treated with the SQUEEZE routine [Spek (2009). Acta Cryst. D65, 148-155].

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Acta Cryst. (2017). A73, C690
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The conformation and tautomeric structure of (Z)-4-[5-(2,6-difluoro­benzyl)-1-(2-fluoro­benzyl)-2-oxo-1,2-dihydro­pyridin-3-yl]-4-hy­droxy-2-oxo-N-(2-oxopyrrolidin-1-yl)but-3-enamide, C27H22F3N3O5, in the solid state has been resolved by single-crystal X-ray crystallography. The electron distribution in the mol­ecule was evaluated by refinements with invarioms, aspherical scattering factors by the method of Dittrich et al. [Acta Cryst. (2005), A61, 314-320] that are based on the Hansen-Coppens multipole model [Hansen & Coppens (1978). Acta Cryst. A34, 909-921]. The [beta]-diketo portion of the mol­ecule exists in the enol form. The enol -OH hydrogen forms a strong asymmetric hydrogen bond with the carbonyl O atom on the [beta]-C atom of the chain. Weak intra­molecular hydrogen bonds exist between the weakly acidic [alpha]-CH hydrogen of the keto-enol group and the pyridinone carbonyl O atom, and also between the hydrazine N-H group and the carbonyl group in the [beta]-position from the hydrazine N-H group. The electrostatic properties of the mol­ecule were derived from the mol­ecular charge density. The mol­ecule is in a lengthened conformation and the rings of the two benzyl groups are nearly orthogonal. Results from a high-field 1H and 13C NMR correlation spectroscopy study confirm that the same tautomer exists in solution as in the solid state.

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The mol­ecule of the title compound, C13H12BrN3O4, is non-planar, as indicated in the dihedral angle of 59.5 (4)° formed between the least-squares planes through the imidazole and benzene rings. In the crystal, mol­ecules are connected via C-H...O contacts, forming a supra­molecular chain.

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Acta Cryst. (1984). A40, C370
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The crystal structure of vipoxin, a neurotoxic postsynaptic heterodimeric complex from the venom of Vipera ammodytes meridionalis, has been determined by the molecular-replacement method and refined to 1.4 Å resolution.

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In 2,4-di­hydroxy­benz­aldehyde 2,4-di­nitro­phenyl­hydrazone N,N-di­methyl­form­amide solvate {or 4-[(2,4-di­nitro­phenyl)­hydrazono­methyl]­benzene-1,3-diol N,N-di­methyl­form­amide solvate}, C13H10N4O6·C3H7NO, (X), 2,4-di­hydroxy­aceto­phenone 2,4-di­nitro­phenyl­hydrazone N,N-di­methyl­form­am­ide solvate (or 4-{1-[(2,4-di­nitro­phenyl)hydrazono]ethyl}benzene-1,3-diol N,N-di­methyl­form­amide solvate), C14H12N4O6·C3H7NO, (XI), and 2,4-di­hydroxy­benzo­phenone 2,4-di­nitro­phenyl­hydrazone N,N-di­methyl­acet­amide solvate (or 4-­{[(2,4-di­nitro­phenyl)hydrazono]phenyl­methyl}benzene-1,3-diol N,N-di­methyl­acet­amide solvate), C19H14N4O6·C4H9NO, (XII), the molecules all lack a center of symmetry, crystallize in centrosymmetric space groups and have been observed to exhibit non-linear optical activity. In each case, the hydrazone skeleton is fairly planar, facilitated by the presence of two intramolecular hydrogen bonds and some partial N-N double-bond character. Each molecule is hydrogen bonded to one solvent mol­ecule.

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