1-[(Pyridine-2-ylamino)methyl]pyrrolidine-2,5-dione: Supramolecular Aggregation via Cooperative H-bonded Network of N–H···N and C–H···O Interactions

Abstract  

In the crystal structure of the title compound, C₁₀H₁₁N₃O₂, the pyrrolidine ring adopts a puckered envelope conformation. The supramolecular architecture is dictated by the cooperative H-bonded network of centrosymmetric dimers of N–H···N and C–H···O interactions. Two edge to face C–H···π interactions involving the centroid of the pyrrolidine ring contribute to the supramolecular aggregation.     

Analysis of C–H···O Intermolecular Interactions in 4-Androstene-3,17-dione

Abstract  4-Androstene-3,17-dione was synthesized for its crystallographic analysis and to investigate the role of intra- and intermolecular interactions in steroids. It crystallizes in the orthorhombic space group P2₁2₁2₁ with unit cell parameters, a = 7.330(2) ?, b = 13.095(11) ?, c = 16.856(17) ?, V = 1,618(5) ?³ and Z = 4. The structure has been solved by direct methods using X-ray diffraction techniques and the refined final reliability index for the computed structure is 0.033 for 1,655 observed reflections. Two six-membered rings B and C exist in chair conformation while ring A occupies a sofa conformation. The five-membered ring D depicts envelope conformation. The C–H···O intermolecular hydrogen interaction results into a ring like configuration which makes the dimers. Index Abstract   Androgen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates by binding to androgen receptors [1]. Androgens have been used in breast cancer when excision or radiotherapy have failed to control the progress of local recurrent disease. They are also used in case where the primary tumour is inoperable or is unsuited for, or resistant to, radiotherapy. Androgens are also believed to be responsible for linear bone growth in both males and females, probably in conjunction with somatotrophin [2]. In continuation to our work on the single crystal growth of X-ray diffraction quality crystals and crystallographic analysis of steroidal molecules, [3-7] synthesis and crystallographic study 4-androstene-3,17-dione is reported in this paper.     

C–H···F Hydrogen-Bonded Assembly of Ni(II) and Cu(II) Complexes Generate 3D Supramolecular Frameworks

Abstract  Syntheses and X-ray structural characterizations of two new complexes [Ni(imi)₆](pfbz)₂ (1) and Cu(imi)₂(pfbz)₂ (2) (imi = imidazole, pfbz = pentafluorobenzoate) are reported. The first complex crystallizes in the triclinic space group P-1 with the crystal cell parameters a = 9.180(2) ?, b = 9.742(3) ?, c = 11.466(3) ?, α = 76.947(18)°, β = 80.629(18)°, γ = 78.043(19)°, V = 970.0(4) ?³ and Z = 1. The second complex crystallizes in the triclinic space group P-1 with the crystal cell parameters a = 7.3250(12) ?, b = 7.6685(10) ?, c = 10.888(4) ?, α = 92.80(2)°, β = 101.92(2)°, γ = 115.038(12)°, V = 535.7(2) ?³ and Z = 1. Examination of the structures shows that both complexes form three-dimensional hydrogen bonded networks in which C–H···F hydrogen bonds play significant roles. Index Abstract   C–H···F Hydrogen-Bonded Assembly of Ni(II) and Cu(II) Complexes Generate 3D Supramolecular Frameworks Chun-Hua Ge, Xiao-Yan Zhang, Fang Yu, Ya-Nan Guo, Xiang-Dong Zhang* and Qi-Tao Liu C–H···F interactions link simple complexes to form intricate three-dimensional supramolecular networks.      

C–H···π and C=O···π Intermolecular Interactions in Dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate

Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P2₁/c with a = 11.0707(3) ?, b = 5.23700(10) ?, c = 16.6997(5) ?, β = 103.5385(16)°, Mr = 376.40, V = 941.30(4) ?³, Z = 2. Each molecule possesses C _i symmetry with the two halves of the molecule related by an inversion centre. C–H···π and C=O···π interactions held the molecules together. Index Abstract C–H···π and C=O···π intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C _i symmetry. The molecules are assembled in chains via carbonyl···π interactions. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.     

Crystal and molecular structure of 7-hydroxyflavone monohydrate, C14H10O3·H2O

The X-ray crystal structure of 7-hydroxyflavone monohydrate, C₁₄H₁₀O₃ · H₂O, is determined. The compound crystallizes in the monoclinic space group, P2₁/n with a = 3.801(3), b = 19.665(4), c = 16. 039(6), = 93.69(3)°, and = 0.68 mm^–1 for Z = 4. The phenyl ring of the flavone moiety is rotated 18.6(1)° out of the penzopyran plane, which is a typical value for flavones. In the crystal lattice, there are wide channels which are lined mainly by C–H groups. The water molecules enclosed in these channels are severely disordered.     

Hardness and refractive index of Ca–Si–O–N glasses

Vickers hardness and refractive index was determined for Ca–Si–O–N glasses with 14.6–58 e/o N and 19–42 e/o Ca. By applying slow cooling rates, transparent glasses were obtained for compositions near Ca_9.94Si₁₀O_17.73N_8.14, while the majority of the glasses were opaque due to small inclusions of elemental Si and/or Ca-silicide. Determined glass densities varied between 2.80 and 3.25 g/cm³. Hardness was found to vary from 7.3 to 10.1 GPa at a load of 500 g and, respectively increase and decrease linearly with N and Ca content. The refractive index was found to increase linearly with N content from 1.62 to 1.95 and showed no significant dependence on Ca content.     

Influences of cooperative hydrogen bonding economy on protein-nucleic acid complexation: Structure of unidecahydrated Inosine C5′-monophosphate and L-glutamine (2C10H13N4O8P · C5H10N2O3 · 11H2O) cocrystal at atomic resolution

The crystal structure of a unidecahydrated co-complex between two Inosine 5-monophosphate (IMP) and one L-glutamine has been determined at atomic resolution by X-ray crystallographic methods. The crystal belongs to the monoclinic space group P2₁ with cell dimensions a = 8.690(2), b = 21.900(3), c = 12.370(1) Å, and = 110.59(3)°. This structure reveals the recognition mechanism of glutamine to the nucleotide through direct and water-mediated hydrogen bonds. The phosphate oxygen (O23) seems to prefer the nonspecific interaction with the functional sites of glutamine (NA···O23 = 2.672, OH···O23 = 3.063, OE···O23 = 3.104 Å), whereas the bases prefer specific (N23···O = 2.874 Å) bindings. But here no specific interaction has been observed at N17 and N27, which were observed in serine—IMP complex. However, the solvent mediated N17···OW3···N27 hydrogen bonds for stabilization of the stacked purine bases have been observed as in other aminoacid-nucleotide cocrystals. The striking habit of glutamine to occupy the nearly same region of the nucleotide cocrystal as was found in the serine—IMP complex through substantial replacement of free and bound water molecules, shows certainly the cooperative hydrogen bonding economy of water molecules.     

X-Ray Diffraction and Thermographic Study of Mesomorphic 4-Acylphenyl 4'-Nonyloxybenzoate CH3C(O)C6H4–OC(O)–C6H4–OC9H19

Crystallography Reports - The structure and thermal properties of mesomorphic phenyl benzoate CH3–C(O)–C6H4–OC(O)–C6H4–OC9H19 (I) were studied by differential scanning...     

Crystal Structure of 2-Thiophenecarboxamide: A One-dimensional Tubular Structure Formed by N–H···O Hydrogen Bonds

Abstract  The crystal structure of 2-thoiphenecarboxamide is described. The compound crystallizes in the orthorhombic Pna2₁ space group with unit cell parameters a = 10.044 (3) ?, b = 14.203 (4) ? and c = 15.941 (3) ?; V = 2,274.1 (10) ?³. The asymmetric unit contains four independent molecules which are linked by N–H···O hydrogen bonds. The asymmetric unit at (x, y, z) is connected with another one, produced by the a-glide plane at 0.75 along the b-axis, that lies at (x + 0.5, −y + 1.5, z) by two N–H···O hydrogen bonds and by a C–H···O weak hydrogen bond to form a one-dimensional tube. Adjacent tubes are linked by C–H···pi interactions to form a three-dimensional framework. Graphical Abstract  The crystal structure of 2-thiophenecarboxamide, contains four crystallographically independent molecular components in the asymmetric unit linked by four N–H···O hydrogen bonds and a weak C–H···O hydrogen bond and form a one-dimensional tube. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Structure of progesterone hydroquinone monohydrate (1∶1∶1), C21H30O2·C6H6O2·H2O

The crystal structure of progesterone hydroquinone monohydrate was determined by means of X-ray diffraction methods:M _r=442.6, orthorhombic,P2₁2₁2₁,a=14.680(2),b=22.725(3),c=7.334(1) Å,V _a=2446.6(6) ų,Z=4,D _x=1.190 M gm^–3, MoK radiation ,(MoK)=0.75 cm^–1,F(000)=948. The structure was solved usingMultan;R=0.059,R _w=0.059 for 2736 reflections. This progesterone molecule has the most flattenedA ring, relative to the rest of the skeleton, of all progesterone molecules studied so far. Steroid, hydroquinone, and water molecules form, by means of hydrogen bonds, two parallel chains connected with each other by hydrogen bonds.The authors thank Dr. A. Szyczewski for supplying crystals. This research was supported by the project RP.II.10 from the Polish Ministry of National Education and by PHS Grant No. DK26546.     

Mesophase-Preceding Crystal Packing of 4,4'-Dialkyl-Substituted Salicylideneanilines; C10H21O–C6H3(OH)–CH=N–C6H4–С7Н13) Structure

Crystallography Reports - The crystal structure of 4,4'-substituted salicylideneaniline C10H21O–C6H3(OH)–CH=N–C6H4–C7H13 has been investigated by X-ray diffraction. A...     

Synthesis and crystal structure of [Ni(H2O)6](C19H17O9S)2·2H2O

A water soluble flavonoid sulfate, [Ni(H₂O)₆](C₁₉H₁₇O₉S)₂·2H₂O was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. The crystal of it belongs to triclinic crystal system, space group P–1. The results show that the title compound consists of [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and H₂O. Ni(II) is located on the symmetry center and octahedrally coordinated by six water molecules. A variety of hydrogen bonds among [Ni(H₂O)₆]²⁺, C₁₉H₁₇O₆SO₃ ⁻ and the lattice water molecules build a hydrophilic region. Aromatic π–π stacking interactions assemble isoflavone skeletons into a column and the columns form a hydrophobic region of the title compound. The sulfo-groups bridge the hydrophilic regions and the hydrophobic regions as well as the inorganic components and organic components. Hydrogen bonds, stacking interactions and the electrostatic interactions between cation [Ni(H₂O)₆]²⁺ and anion sulfonate C₁₉H₁₇O₆SO₃ ⁻ lead the moieties to a three-dimensional structure.     

Crystal Packing of Potentially Mesomorphic Azobenezene Derivatives R1–C6H4–N=N–C6H4–R2 (R1, R2 = CH3COO,C2H5O; CH2=C(CH3)COO,C2H5; C6H13COO,C2H5O)

Crystallography Reports - The structure and thermal properties of azobenzene derivatives R1–C6H4–N=N–C6H4–R2, where R1/R2 = CH3COO/C2H5O (I), CH2=C(CH3)COO/C2H5 (II), or...     

Crystal structure and hydrogen-bonding system of cholic acid hemihydrate,C24H40O5·1/2H2O

Crystals of the hemihydrate of this bile acid are hexagonal, space groupP6₅22, a=b=13.736(8)Å,c=85.06(6)Å,V=13,899ų. The asymmetric unit contains two independent steroid molecules and one water molecule, the latter disordered over two nonequivalent positions.Z=12[2(C₂₄H₄₀O₅)·1(H₂O)],F(000)=5496. Structure solution by direct methods; refinement by least-squares, toR=0.072. The complex hydrogen-bond system comprises: (a) three standard ordered O-HO hydrogen-bonds; (b) what is probably a symmetrically hydrogen-bonded carboxylic acid dimer, with a twofold rotation axisin the plane of the two carboxyl groups; (c) helical hydrogen-bonding chains about each 6₅ axis, disordered over four possible arrangements. In these helical chains, the six independent hydrogen-bonds can as a group be in either of two systems of nearly equivalent flip-flop arrangements: O-HO OH-O. Each helical system includes water, which can occupy either of two sites; thus, there is further disorder involving two sets of nonequivalent hydrogen-bonds with water as donor and acceptor. Many aggregation features here differ markedly from those in the crystal structures of either anhydrous cholic acid or cholic acid monohydrate.