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1.
3‐Phenyl‐chroman‐4‐one is the basic unit of isoflavonoids which are found in the plants of the sub‐family papilionoidae of Leguminosae. They are known to possess antifungal and antibacterial properties. Crystal data of the title compound : Monoclinic, space group P21/c, a = 14.021(3), b = 18.682(4), c = 11.362(2) Å, β = 95.75(3)°, R = 0.066. The two phenyl rings directly attached to the pyrrolidine ring are nearly perpendicular to it. The dihydropyrone moiety adopts a half‐chair conformation while the cyclohexane ring attached to the pyrrolidine ring adopts a chair conformation. The best plane passing through the chroman‐4‐one moiety makes a dihedral angle of 82.2(3)° with the pyrrolidine ring. The molecule is stabilized by one intra‐ and two intermolecular C‐H...O hydrogen bonds.  相似文献   

2.
Using X-ray crystal structure analysis of the title compound the positions of all the atoms (including all H atoms) in the monoclinic unit cell with the parameters a = 13.900 Å, b = 5.138 Å, c = 17.956 Å and β = 91.05° and the space group P 21/n were localized. The existence of an intramolecular N—H(N)…︁ O(1)-bridge was inferred, whose H-bridge acceptor predominantly is the π-electron density of the carbonyl group. At the same time the H(N) atom participates in the intermolecular bridge N H(N)…︁ O′(1) to the symmetry-equivalent neighbouring molecule. H-bridge-like interactions of the two phenyl hydrogen atoms H(6) and H(15) to the carbonyl oxygen O(2) have also been inferred from the torsion angles.  相似文献   

3.
Dichloropicric acid is orthorhombic, space groupP212121; at 24°a=5.672(3),b=8.044(3),c=22.491(7) Å,D x=1.929(2) g-cm?3,V=1026(1) Å3,Z=4. The phenolic OH group is intramolecularly hydrogen bonded to one of theortho nitro groups with an O...O distance of 2.524(5) Å. As a consequence, this nitro group is twisted out of the plane of the benzene ring by only 20.1° in spite of crowding by the adjacent chlorine atom which is only 2.764(3) Å from the O atom in the nitro group. The two non-hydrogen bonded nitro groups have twist angles of 73.9 and 84.1°. There is no evidence of intermolecular hydrogen bonding with any adjacent dichloropicric acid molecule.  相似文献   

4.
The crystal structure and some physico-chemical properties of MnCl2·Pro·H2O (Pro=L-proline) were studied. This compound is stable up to approximately 313 K. Upon heating the complex loses a molecule of water and is transformed into the oxide in two steps. The IR spectrum was recorded. The compound crystallizes in the orthorhombic space groupP212121 witha=7.112(2) Å,b=10.196(2) Å,c=13.249(3) Å andZ=4. The manganese atoms in the polymeric chain are bridged by two chlorine atoms and oxygen atoms from the carboxylate group of L-proline. The Mn?Cl bond distances range from 2.535(1) Å to 2.581(1) Å, the Mn?O bond distances range from 2.135(2) Å to 2.153(2) Å and Mn?Mn bond distances are 3.556(1) Å. One molecule of water is hydrogen-bonded with a nitrogen atom of the L-proline ring.  相似文献   

5.
A mononuclear copper(II) complex, [Cu(dmpp)(OCN)2(H2O)], was synthesized using 2,6‐bis (3,5‐dimethylpyrazolyl) pyridine (dmpp) and cyanate anion (OCN), and characterized by single crystal X‐ray diffraction. The coordination around the Cu atom is a distorted square‐pyramid involving three N atoms from the dmpp ligand and one N atom from OCN at the basal plane. The O atom of the OCN group is located at the apical position. The Cu atom is located 0.2782(1) Å above the basal plane. The Cu atom is coordinated by different donor atoms of the OCN groups. The complex crystalizes in monoclinic space group P21/n, with unit cell dimensions a= 12.4413(12), b=11.1457(13), c=14.2203(12) Å, β=108.817(3)°, V= 1866.5(3) Å3. The cell containes 4 molecules. In the crystal, there are three intermolcular and three intramolecular hydrogen bonds interactions. The Cu atom and crystal water O interactions is 5.574 Å. © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim  相似文献   

6.
The crystal structure of R(–)-1-tosyl-2-methylpyrrolidine has been determined by X-ray structure analysis. The compound crystallizes in the monoclinic space group P21 with cell parameters a = 7.858(1), b = 14.929(6), c = 11.128(1) Å, β = 105.42(1)°. The structure has been solved by direct methods and refined to R = 0.046. There are two crystallographically independent molecules A and B in the asymmetric unit. The pyrrolidine ring of molecule A is disordered with atom C4 occupying two possible sites. The S atom has a distorted tetrahedral coordination in both the molecules. Two bifurcated hydrogen bonds are observed. Molecules are held together by hydrogen bonds.  相似文献   

7.
The structure of 3-(p-nitrobenzoyl)-2-oxooxazolo[3,2-a]pyridine is determined by the powder diffraction technique. The crystals are monoclinic, a = 13.642(2) Å, b = 22.278(3) Å, c = 3.917(1) Å, β = 90.63(2)°, Z = 4, and space group P21/n. The structure is solved by a modified Monte Carlo method and refined by the Reitveld method. The six-membered heterocycle is characterized by the alternation of partially single and partially double bonds. The system of two conjugated heterocycles is planar and forms a dihedral angle of 46.1(1)° with the plane of the phenyl ring. The nitro group is virtually coplanar with the phenyl fragment. An extensive system of intramolecular and intermolecular contacts involving hydrogen, oxygen, and nitrogen atoms is observed in the crystal.  相似文献   

8.
Aqua{pentahydrogennitrilotris(methylenephosphonato)}lithium hydrate is a linear coordination polymer. Its crystal structure is described in space group P1, Z = 2; a = 5.5732(2), b = 7.0106(2), and c = 16.9010(5) Å; α = 97.515(2)°, β = 94.551(2)°, and γ = 95.123(2)°. The tetrahedral coordination of the Li atom includes two oxygen atoms of a phosphonate ligand, one oxygen atom of another phosphonate ligand, and a water molecule. Complex formation is accompanied by closing of the eight-membered Li–O–P–C–N–C–P–O chelate ring. Polymeric chains run along the [100] direction. The chains are connected by hydrogen bonds.  相似文献   

9.
The crystal and molecular structure of the benzylisoquinoline alkaloid papaverine hydrochloride, C20H21NO4. HCl, has been determined with CuKα diffractometer data by direct methods. The compound crystallizes in the monoclinic space groupP21/c (No. 14) witha= 13.059(3),b = 15.620(3),c = 9.130(2) Å and β = 92.14(1) °. The structure was refined by full-matrix least-squares methods toR = 0.052 using all 2652 reflections. The nitrogen atoms is protonated and forms a strong hydrogen bond with the chloride ion, the N ... Cl distance being 3.01 Å. The isoquinoline ring is slightly non-planar but the benzene ring is planar within experimental error. The dihedral angle between the benzene ring and the best plane through the isoquinoline group is 109 °. The molecular structure of papaverine is of interest in gaining a better understanding of its pharmacological action on smooth muscle.  相似文献   

10.
The compound piperidino-acet-m-bromo-anilide crystallizes in the orthorhombic space group Pbca with 8 molecules in the unit cell of dimensions a = 23.656; b = 12.664; c = 9.372 Å. The crystal structure was determined. The positions of all hydrogen atoms were located. The intermolecular hydrogen bond N(1)-H(N1)… 0 has an influence on the conformation of the molecule. The angle between the plane of the phenyl ring and the plane of the carbonamide group is 36.8°.  相似文献   

11.
Trans‐bis(2‐pyridinepropanol)bis(saccharinato)nickel(II), [Ni(sac)2(pypr)2], where sac and pypr are the saccharinate anion and the 2‐pyridinepropanol molecule, respectively, crystallizes in the triclinic space group P (No. 2) with a = 8.1981(8), b = 9.9680(10), c = 10.4956(10) Å, α = 90.740(3)° β = 108.142(3)°, γ = 111.025(3)°, Z = 1, V = 1.537 Å3. The structure of the nickel(II) complex consists of neutral molecules in which the nickel(II) ion sits on a center of symmetry and is octahedrally coordinated by two sac ligands, and two neutral pypr ligands. The pypr acts as a bidentate N‐ and O‐donor ligand forming a seven‐membered chelate ring, while sac behaves as a monodentate O‐donor ligand via the carbonyl O atom. The Ni‐N bond distance is 2.1016(15) Å, whereas the Ni‐Opypr and Ni‐Osac bond distances are 2.1280(12) and 2.0792(11) Å, respectively. The individual molecules are held together with a strong hydrogen bond between the hydroxyl O atom of pypr and N atom of sac and the C‐H…O type weak hydrogen bonds between some ring hydrogen atoms of pypr and sac, and the carbonyl and sulfonyl O atoms of sac in the neighbouring molecules. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

12.
The crystal structure of the nacrite mineral of the kaolin group (space group Cc; R = 2.76%; 634 unique reflections) is refined from the digital oblique-texture electron diffraction patterns obtained with the use of imaging plates. The maxima characterizing the locations and potentials of the hydrogen atoms of the hydroxyl groups are revealed from the difference Fourier-potential syntheses. The O-H interatomic distances and the angles of inclination of the O-H bond with respect to the ab plane are equal to 0.97 Å and ?18.3° for the inner hydroxyl group and 0.92, 0.85, 0.93 Å and 60.8°, 67.8°, 58.4° for the outer hydroxyl groups, respectively. The Odonor-Oacceptor interatomic distances are 2.940, 2.949, and 3.121 Å. It is established that the electrostatic potential distributions of the hydrogen atoms of the inner hydroxyl group and one of the outer hydroxyl groups located in the vicinity of the symmetry pseudoplane m of the layer are characterized by anisotropy, which can indicate a statistical distribution of these hydrogen atoms.  相似文献   

13.
The structure of single crystals of 2,4,6-trinitro-N-methyl-N-nitroaniline C7H5N5O8 (I) is determined by X-ray diffraction analysis. The unit cell parameters are a = 14.137(3) Å, b = 10.621(2) Å, c = 7.376(2) Å, γ = 95.19 (5)°, space group P21/b, and Z = 4. The structure is solved by the direct method and refined in the anisotropic approximation to R = 0.051 for 1917 reflections with I > 2σ(I). All hydrogen atoms are located and refined in the isotropic approximation. The carbon skeleton of the aromatic nucleus of the molecule tends to adopt the C(2),C(5)-boat conformation. The angle of rotation of the planar NNO2 group with respect to the plane of the six-membered ring is 123.1(2)°. The NO2groups that are bonded to the aromatic nucleus of the molecule are also rotated relative to this plane.  相似文献   

14.
The crystal structure of lepidocrocite γ-FeO(OH) with the lattice parameters a = 3.072(2), b = 12.516(3), c = 3.873(2) Å, sp. gr. Cmcm has been refined by the electron-diffractometry data for 135 crystallographically nonequivalent reflections up to R = 0.048. Using the difference syntheses of the Fourier potential, we established, for the first time, the anisotropy in the distribution of the electrostatic potential of hydrogen and the statistical occupancy (with the probability of 1/2) by hydrogen atoms of two positions in the m plane normal to the a-axis at a distance of 0.27 Å from the twofold axis. The O-H distance equals 0.97(3) Å, the O-H?O angle, 135°. The average Fe-O distance in octahedra is 2.022 Å.  相似文献   

15.
The 1.1′-Bis-[phenylglyoxyloyl]-ferrocen (PGF) crystallizes within the monoclinic space group P1/c with the lattice constants a = 7,338 Å, b = 16,872 Å, c = 8,046 Å, β = 87,0°. The PGF belongs to metal-π-complexes. With the iron atom in the center of symmetry, both the heavy atom ligands are centrosymmetric-to each other. The two cyclopentadinyl rings linked to the iron atom are arranged in the sandwichtype with staggered conformation. The mean planes are separated by 3,32 Å. In a single phenyl-glyoxyloyl molecule exists an expanded Csp2–Csp2 bondlength (1,528 Å). The two plane parts of the molecule are twisted around this bond. These two plane parts consist on the one hand of the carbon-5-ring and a C  O group and on the other hand of the carbon-6-ring and a C  O group. The dihedral angle is 62,5°. The expanded bond length mentioned is explained by Coulomb repelling forces of partially charged atoms. The packing of the molecules in the crystal lattice is discussed in detail.  相似文献   

16.
The crystal structure of the [NpO2(NO3)(Terpy)(H2O)] complex between pentavalent neptunium and 2,2′,6′,2″-terpyridine is determined. The crystal data are as follows: a = 11.130(3) Å, b = 7.916(2) Å, c = 18.324(5) Å, β = 100.873(6)°, V = 1585.5(8) Å3, Z = 4, space group is P21/n, R = 0.044, and wR(F 2) = 0.092. The coordination polyhedron of the Np atom is a pentagonal bipyramid whose equatorial plane includes three nitrogen atoms of the Terpy molecule and two oxygen atoms of the nitrate ion and the water molecule.  相似文献   

17.
The crystal structure of L-alanine phosphate (C3O2NH7 · H3PO4) is determined by the single-crystal diffraction technique; a = 11.918(1) Å, b = 9.117(1) Å, c = 7.285(1) Å, γ = 104.7(1)°, space group P21, and Z = 4. The amino group of the alanine is protonated by the hydrogen atom of the phosphoric acid. Pairs of H2PO 4 ? hydrogen-bonded ions are packed into layers alternating with layers of alanine molecules in the crystal. No hydrogen bonds are formed immediately between the alanine molecules.  相似文献   

18.
The [Co2 L 4(C4H9COO)4(H2O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) Å, b = 16.3858(10) Å, c = 16.4262(10) Å, α = 100.538(10)°, β = 101.199(10)°, γ = 90.813 (10)°, Z = 2, and space group P \(\bar 1\). The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygen atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.  相似文献   

19.
C6H10N2O2, P1 , a = 6,607(2) Å, b = 8,538(2) Å, c = 6,392(2) Å, α = 102,43(2)°, β = 91,11(2)°, y = 79,82(2)°, V = 349,1 Å3, Z = 2, Dm = 1,36 g × cm−3, Dx = 1,35 g × × cm−3, MoKα radiation, λ = 1.71069 Å, μ(MoKα) = 1.11 cm−1. The structure was solved by direct methods. The parameters were refined by full matrix least squares technique to a final R = 0.088 for 834 reflections with ∥F0∥ > 4σ(F0). The dihedral angle between the least-squares plane through the pyrrolidine ring and that through the acetamide group is 90.4°. The N H … O hydrogen bonds connect molecules to form bands parallel to the z axis.  相似文献   

20.
The structure of the [(DCH-6A ? NH4)(H2O)I]2 complex obtained by the reaction between the cis-syn-cisisomer of dicyclohexano-18-crown-6 (DCH-6A) and NH4I has been determined by X-ray diffraction analysis. The crystals are triclinic, a = 9.314(3) Å, b = 11.951(2) Å, c = 12.040(1) Å, α = 77.36(1)°, β = 81.59(1)°, γ = 80.41(2)°, space group $P\bar 1$ , Z = 2, and the final R factor is 0.044. The structure is built up of the (DCH-6A ? NH4) + cationic complexes, iodide anions, and water molecules. The ammonium ion forms three hydrogen bonds of the NH?O type [N?O, 2.881(5)–2.890(5) Å] with the oxygen atoms of the crown ether molecule. The organic cations are joined together into centrosymmetric dimers through the system of hydrogen bonds of the NH?OH type. The I??O distances (where the O atom belongs to the bridging water molecule) fall in the range 3.558(4)–3.610(4) Å.  相似文献   

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