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In the title compound, [Ni(C40H28N4S4)]·0.5C6H6, the NiII atom is in a square-planar geometry defined by four pyrrole N atoms. There is considerable buckling in the porphyrin ring with the dihedral angles between the N4 donor set and the pyrrole rings being in the range 16.24 (5)–22.47 (5)°. Each of the six-membered chelate rings is twisted about an Ni—N bond and the dihedral angles between diagonally opposite chelate rings are 21.36 (4) and 23.87 (4)°; each pair of rings is oriented in opposite directions. The methyl­thienyl rings are twisted out of the plane of the central N4 core with dihedral angles in the range 75.98 (2)–88.70 (5)°. All four methyl­thienyl groups are disordered over two sets of sites, as is commonly found with such groups, with occupancies of 0.553 (8):0.447 (8), 0.579 (7):0.421 (7), 0.796 (6):0.204 (6) and 0.956 (7):0.044 (7). The benzene solvent mol­ecule was found to be present in half-occupancy.

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In the title compound, C11H9NO2Se, the pyridine and phenyl rings are almost perpendicular, with the dihedral angle between their mean planes being 79.16 (7)°. In the crystal, the mol­ecules pack so as to form ruffled sheets in the (110) plane connected by weak C—H...O inter­actions. In addition, there are weak π–π inter­actions between the mean planes of both the phenyl [centroid–centroid perpendicular distance of 3.591 (2) Å and slippage of 1.854 (2) Å] and pyridine rings [centroid–centroid perpendicular distance of 3.348 (2) Å and slippage of 1.854 (2) Å].

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The title compound, C22H30BrNO, is an alk­oxy­amine compound, an effective initiator in nitroxide-mediated free radical polymerization. It was prepared as a mixture of two diasteromers; the crystal for the X-ray analysis showed one of these as a pair of R,S and S,R enanti­omers. The tert-butyl and isopropyl groups are in an almost anti conformation in the crystal [C—N—C—C torsion angle = −168.8 (1)°], and the methyl group of the ethoxy group is in an approximate anti relationship to the tert-butyl group. The dihedral angle between the phenyl and benzene rings is 33.12 (7)°. The Br atom is disordered over two positions, with occupancies of 0.9139 (16) and 0.0861 (16). In the crystal, weak C—H...Br contacts link the mol­ecules into chains along [-110].

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The title compound, C5H11NO2·H2O, is an isomer of the α-amino acid valine that crystallizes from water in its zwitterion form as a monohydrate. It is not one of the 20 proteinogenic amino acids that are used in living systems and differs from the natural amino acids in that it has no α-H atom. The compound exhibits hydrogen bonding between the water mol­ecule and the carboxyl­ate O atoms and an amine H atom. In addition, there are inter­molecular hydrogen-bonding inter­actions between the carboxyl­ate O atoms and amine H atoms. In the crystal, these extensive N—H...O and O—H...O hydrogen bonds lead to the formation of a three-dimensional network.

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The asymmetric unit of the title compound, C21H18ClFO3, contains two independent mol­ecules. In one mol­ecule (A), the 4-chloro­phenyl, oxo­cyclo­hex-3-ene, carboxyl­ate, and ethyl groups were refined as disordered over two sets of sites with a 0.684 (5):0.316 (5) ratio. The cyclo­hexene ring in the disordered mol­ecule is in a slightly distorted envelope conformation for the major component (with the C atom bound to the carboxylate group being the flap atom) and in a screw-boat conformation for the minor component. In the ordered mol­ecule (B), the cyclo­hexene ring is in a half-chair conformation. The dihedral angles between the mean planes of the fluoro- and chloro-substituted benzene rings are 89.9 (7) (only the major component is considered for A) and 76.4 (7)° (B). In the crystal, inversion dimers are observed along with weak C—H...O hydrogen bonds, which form chains along [100].

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The title compound, C5H9NO4·H2O, is an isomer of the α-amino acid glutamic acid that crystallizes from water in its zwitterionic form as a monohydrate. It is not one of the 20 proteinogenic α-amino acids that are used in living systems and differs from the natural amino acids in that it has an α-methyl group rather than an α-H atom. In the crystal, an O—H...O hydrogen bond is present between the acid and water mol­ecules while extensive N—H...O and O—H...O hydrogen bonds link the components into a three-dimensional array.
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