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1.
Triphenyltin diethylphosphonoacetate, which crystallizes in the monoclinc space groupP21/c (a=15.154(4),b=9.159(3),c=17.685(4) Å, =91.410(8)°), adopts a polymeric structure in which planar triphenyltin cations (C—Sn—C=357.3(6)°) are axially linked by the diethylphosphonoacetato anions (Sn–Oesteryl=2.129(3), SnOphosphoryl=2.420(3) Å; O–SnO=171.9(1)° into chains that propagate by translations along theb-axis. The structure has been erfined toR=0.037 for 3384I3(I) reflections.  相似文献   

2.
The crystal structure of tylophorine (Chemical name 2,3,6,7 tetramethoxy phenanthro [9,10:6, 7] indolizidine. Contribution No. 0871.) methiodide monohydrate has been determined. C25H30NO 4 + I·H20, triclinic, P,a=8.831(1)Å, b=10.842(2),c=13.902(2), =105.0(1)o, =104.7(1), =97.3(1),V=1210.22Å3, Z=2,D x =1.428 g./cm–3, (CuK)=1.54184Å, (CUK)=107.2 cm–1, F(000)=544,T=295oK,R=0.038,Rw=0.046, for 2331 observed reflections withI2(I). Apart from van der Waals forces, the structure is stabilized by two hydrogen bonds of the type Ow(H) ... O and Ow(H) ... I involving the water molecule as the donor and atom O4 of the methoxy group and I as acceptors.  相似文献   

3.
The crystal structure of the title compound, C20H14N2O2Cl2, has been determined by single crystal X-ray diffraction techniques. It crystallizes in the orthorhombic system witha=7.532(3)Å,b=18.563(2)Å,c=25.089(3)Å, space groupPbca,V=3507.9(3)Å3,Z=8,F(000)=1584.D x =1.459 g cm–3,M=385.3 a. m. u., (MoK)=0.7107 Å, =3.35 cm–1,T=297°K,R=0.086,R w =0.049 for 2119 unique diffractometer data. The molecules are linked by van der Waals forces.  相似文献   

4.
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.  相似文献   

5.
The (HAgu)2B6H6 · 2H2O compound was synthesized and its crystal structure was determined [R = 0.0385 for 2018 reflections with I > 2σ(I)]. The structure consists of HAgu + cations, centrosymmetric B6H 6 2? anions, and water molecules. The anions have an almost regular octahedral structure. The bond lengths and angles lie within the following narrow ranges: B-B, 1.715–1.726(2) Å; B-H, 1.08–1.14(2) Å; B-B-B, 59.72°–60.29(9)° and 89.63°–90.20(11)°; and B-B-H, 133.2°–137.0(9)°. The HAgu + cations and water molecules are involved in the O-H?O, N-H?O, and N-N?N hydrogen bonds and participate in numerous (N, O)-H?H-B specific interactions with the B6H 6 2? anions, which results in splitting and high-frequency shift of the band of B-H stretching vibrations in the IR spectrum.  相似文献   

6.
The title compound isN,N-DiphenylpiperazineN,N-dioxide octahydrate, C16H34N2O10:M r=414.46, orthorhombic, space groupPnma (No. 62),a=12.327(2),b=9.804(1),c=17.443(4) Å,V c=2108.1(5) Å3,Z=4. The structure was solved by the direct method and refined toR=0.056 for 3032 observed MoK reflections. In theN,N-dioxide molecule, all atoms except those of the methylene groups lie on a crystallographic mirror plane. The piperazine ring takes the chair form, with two N-O bonds oriented axially in atrans configuration. The crystal structure is characterized by strong hydrogen bonding between the water molecules, as well as between theN-oxide groups and water molecules, giving rise to a three-dimensional network structure composed of edge-sharing four-membered, five-membered, six-membered, and fourteen-membered rings.  相似文献   

7.
The title compound crystallizes in space group P21/n, with a = 14.600(2), b = 7.091(2), c = 18.211(5) Å, and = 103.67(2)°. Owing to the centric space group, both C(1) and C(3) chiral centers are either R or S. The acetate group is equatorial, the H(1) and the methyl group at C(3) are axial and reciprocally trans.  相似文献   

8.
The structure of the title compound (C9H12ON·HBr)2O was determined by X-ray diffraction methods. The crystals are monoclinic:C2/c,a=7.645(2),b=19.777(3),c=13.704(3) Å,=98.32(2)°,V c =2050.2 Å3,Z=4,F(000)=968,D m =1.62,D c =1.615 Mg m–3; MoK radiation (graphite crystal monochromator, =0.71073 Å),(MoK)=4.39 mm–1. FinalR factor=0.061 andR w =0.045 for 1566 reflections. The structure was solved by the heavy-atom Fourier method and refined by least-squares procedures. Each asymmetric unit in the unit cell contains one-half of the molecule, with oxygen atom O(2) at a special position with half-occupancy. The molecules are protonated at their nitrogen sites. The structure is stabilized by a three-dimensional network of hydrogen bonds. The ethylamine side chain in the molecular fragment in the asymmetric unit exhibits an extended (trans) conformation that is also found in most of the other adrenergic phenylethylamines.  相似文献   

9.
The salt N-benzylmethylammonium dihydrogenmonophosphate monohydrate is monoclinic with the following unit cell dimensions: a = 6.356(1)Å, b = 8.385(7)Å, c = 11.472(5)Å, = 104.32(1)°, space group P21 with Z = 2. The structure consists of infinite parallel two-dimensional [110] planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than normal van der Waals interactions between the layers.  相似文献   

10.
11.
The crystal structure of 17-methyltestosterone hemihydrate, C20H30O2·1/2H2O, has been determined:M r =312.5, space groupP21212121,a=6.374(2),b=12.807(2),c=43.398(5)Å,V c =3543(2)Å3,Z=8,D x =1.172 mg–3, CuK radiation ( = 1.54184 Å),(CuK)=5.5 cm–1,F(000)=1376. The structure was solved usingMultan. The final conventionalR=0.053 (R w =0.052) for 3634 reflections. The structure contains two crystallographically independent molecules in the asymmetric part of the unit cell that have almost identical geometry.  相似文献   

12.
Crystals of the hemihydrate of this bile acid are hexagonal, space groupP6522, a=b=13.736(8)Å,c=85.06(6)Å,V=13,899Å3. 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.  相似文献   

13.
Crystals of the title compound are monoclinic (C20H22N2O2): space groupP21/n,a=11.800(3),b=13.820(2),c=11.004(3) Å,=92.74(3)°. The structure was solved by direct methods and refined by block-matrix least-squares procedure to giveR=0.078 andRw=0.076 for 1960 reflections above 3(I). The two amide groups are not coplanar with respect to their benzene rings. An intramolecular N-HO hydrogen bond was found in the molecules which are joined in chains by other strong N-HO hydrogen bonds.  相似文献   

14.
The crystal structure of the title lactone, C20H30O9, a potential precursor of uncommon 11-carbon sugar derivatives, has been determined by single-crystal diffraction methods. The compound crystallizes in the orthorhombic space groupP212121 witha=15.581(3),b=14.047(2),c=9.888(2) Å, andZ=4. The structure was solved by direct methods and refined by full-matrix least-squares toR=0.054. The absolute configuration of the seven stereogenic carbon atoms was deduced as 4R, 5R, 6R, 7R, 8S, 9R, 10R, being (R)-(+)-glyceraldehyde its progenitor. An intramolecular O-HO hydrogen bond is present. Weak interaction C-HO links the molecules in sheets parallel to the (100) plane.  相似文献   

15.
[Yb(L(NO3)2(H2O)2](NO3), L = bromo-N,N,N,N-tetraethylmalonamide crystallizes in the triclinic spacegroup P-1 with cell dimensions a = 9.030(9), b = 12.036(12), c = 12.392(13) Å, = 84.52(1), = 77.58(1), = 67.21(1)° , dcalc = 1.935 g cm-3 for Z = 2. The ytterbium atom in the complex cation is nine-coordinate being bonded to two oxygen atoms from the malonamide ligand, two nitrate anions, and three water molecules.  相似文献   

16.
SrCd2Cl68H2O crystallizes in the space group and has the unit cell dimensions a = 9.688(2) Å, b = 11.212(2) Å, c = 7.732(3) Å, = 99.85(21)°, = 89.95(22)°, = 75.81(13)°, and Z = 2. After refinement through full-matrix least-squares methods, the reliability factor R in the final cycle is 4.65%. A very persistent occurrence of twinning by pseudosymmetry was observed. The twin element is a twofold axis [001]. The title compound exhibits five endothermic peaks, which have been detected by differential scanning calorimetry and interpreted from thermogravimetry.  相似文献   

17.
The X-ray crystal structure of 2,4′-biflavonoid has been determined. Colorless regular prism shaped crystals of C30H22O4 crystallize in the space group $P\bar 1$ with cell dimensionsa=11.574(1) Å,b=12.235(1) Å,c=17.428(1) Å, α=108.46(3)o, β=80.08(1)o, γ=103.34(2)o,V=2264.7(4) Å3, andZ=4.  相似文献   

18.
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...  相似文献   

19.
The structure of Zn4Na(OH)6SO4Cl·6H2O, a secondary mineral from Hettstedt, Germany, was determined by single-crystal X-ray diffraction. The crystals are hexagonal,a=8.413(8),c=13.095(24) Å, space group $P\bar 3$ , Z=2. The structure was refined to R=0.0554 and Rw=0.0903 for 970 reflections with I≥3σ(I). The structure can be described as zinc hydroxide layers perpendicular toc, from which sulfates and chlorides extend. The layers are held together by a system of hydrogen bonds involving hexaaquo Na+ ions which occupy the interlayer space.  相似文献   

20.
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) Å3,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.  相似文献   

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