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1.
M. S. Fonar' Yu. A. Simonov J. Lipkowski V. O. Gel'mbol'dt É. V. Ganin A. A. Yavolovskii 《Crystallography Reports》2003,48(4):630-637
Hydrazine 5-amino-1-benzyl-1,2,3-triazole-4-carboxylate hexafluorosilicate trihydrate (I) is synthesized. The crystal structure of the compound synthesized is determined. Crystals I are monoclinic, a = 13.353(1) Å, b = 21.094(2) Å, c = 20.233(2) Å, β = 94.05(3)°, space group P21/c, and R = 0.0584 for 16 601 reflections with I > 2σ(I). In the asymmetric part of the unit cell, four organic cations protonated at the terminal hydrazine nitrogen atoms, two hexafluorosilicate anions, and six water molecules are linked into a three-dimensional framework through hydrogen bonds of the N-H?F, N-H?O, and O-H?F types. 相似文献
2.
Yu. V. Belovitskaya I. V. Pekov E. R. Gobechiya N. A. Yamnova Yu. K. Kabalov N. V. Chukanov J. Schneider 《Crystallography Reports》2002,47(2):223-228
The crystal structures of two ancylite specimens from Khibiny massif (the Kola Peninsula, Russia)—ancylite-(Ce) from alkali hydrothermalites (Sr1.01Ca0.02Ba0.01)Σ1.04(Ce0.52La0.28Nd0.11Pr0.04 Sm0.01)Σ0.96(CO3)2(OH0.83F0.13)Σ0.96 · 0.9H2O and ancylite-(Ce) from carbonatites—have (Sr0.80Ca0.05Ba0.01)Σ0.86(Ce0.62La0.40Nd0.09Pr0.03) Σ1.14(CO3)2(OH0.99F0.15)Σ1.14 · 1.0H2O been refined by the Rietveld method. A focusing STOE-STADIP diffractometer with a bent Ge(111) primary monochromator was used (λ MoK α 1 radiation, 2.16° < 2θ < 54.98°; reflection number 237–437). All the computations for ancylite from alkali hydrothermalites were performed within the sp. gr. Pmc21, a = 5.0634(1) Å, b = 8.5898(1) Å, c = 7.2781(1) Å, V = 316.55(1) Å3, R wp = 1.90; the computations for ancylite from carbonatites were performed within the sp. gr. Pmcn, a = 5.0577(1) Å, b = 8.5665(2) Å, c = 7.3151(2) Å, V = 316.94(1) Å3, R wp = 2.38 in the anisotropic approximation of thermal vibrations of cations and oxygen atoms. 相似文献
3.
Doyle Britton 《Journal of chemical crystallography》1994,24(8):553-556
p-Chloro- and p-bromobenzaldehyde form isomorphous monoclinic crystals, space groupP2
1/a. For p-Cl at –96°C,a=12.945(3),b=3.833(3),c=26.503(9) Å, =103.68(2)°,Z=8,V=1278(2) Å3,Dx=1.461(2) g cm–3, refinement on 2714 reflections,R=0.047. For p-Br at –96°C,a=12.754(5),b=3.919(3),c=27.317(12) Å, =103.28(3)°,Z=8,V=1329(2) Å3,Dx=1.849(3) g cm–3, refinement on 1519 reflections,R=0.062. The molecules do not differ significantly from planarity. They pack in stacks with Cl...Cl or Br...Br contacts at one end and CH...O contacts that are suggestive of hydrogen bonds at the other. There are no O...Cl or O...Br contacts. 相似文献
4.
K. Ravikumar B. Sridhar M. Mahesh V. V. Narayana Reddy 《Journal of chemical crystallography》2006,36(6):381-387
The crystal structures of isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]methyl-5-phenyl-,N-oxide] (C13H13N5O3) (I), isoxazole,3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(4-methylphenyl)-,N-oxide] (C14H15N5O3) (II) and isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(2-methoxyphenyl)-,N-oxide] (C14H15N5O4) (III) have been determined by X-ray diffraction studies. The compound I, crystallized in triclinic space group with unit cell dimensions a = 7.2405(7) ?, b = 7.9936(8) ?, c = 11.6573(11) ?, α = 97.801(2)°, β = 90.884(2)°, γ = 96.250(2)° and Z = 2. Compound II crystallized in orthorhombic space group Pna21 with unit cell dimensions a = 10.1778(10) ?, b = 28.228(3) ?, c = 5.1206(5) ?, and Z = 4. Compound III crystallized in monoclinic space group P21/n with unit cell dimensions a = 7.8439(9) ?, b = 7.8544(9) ?, c = 23.534(3) ?, β = 99.464(2)° and Z = 4. For all three compounds, the five-membered imidazolidine ring adopts an envelope conformation. The crystal structures are stabilized by both the intramolecular N–H···O and intermolecular N–H···N hydrogen bonding. 相似文献
5.
6.
Mollugin was isolated from the extract of Rubia tinctorum roots. Lucidin was obtained by semisynthesis from xanthopurpurin. Mollugin crystallises in space group P-1 (No. 2), a = 8.5857(7), b = 11.473(4), c = 15.024(1) Å, α = 77.64(2)∘, β = 89.36(1)∘, γ = 89.71(2)∘, and V = 1445.5(5) Å3, lucidin crystallises in space group P21/c (No.14), a = 16.800(6), b = 9.637(2), c = 7.073(7) Å, β = 98.01(5)∘, and V = 1134(1) Å3. 相似文献
7.
Tetragonal and monoclinic forms of crystalline pentachloropyridine are described. Both forms may be regarded as layer structures. The basic layer common to the two structures has neighbouring molecules in the same orientation. The tetragonal form has a repeat unit of four layers, whereas the monoclinic form has a repeat unit of two layers. The packing of adjacent layers is essentially the same for both forms.Examples have been found in which the stacking sequences are interrupted, producing faults, twins and diphasic crystals. 相似文献
8.
Irradiation of uracil in ice produces a small quantity of thecis-anti cyclobutyl type photodimer. The molecule contains a pseudo two-fold axis and a cyclobutyl ring which is puckered, with dihedral angles near 150°. Torsion angles about the C(5)-C(6) and C(5)-C(6) bonds are 21°. Each uracil residue has seven atoms which are coplanar to within 0-07 Å, while C(6) and C(6) are 0·38 Å and 0·35 Å out of the planes of their respective residues. Each molecule participates in eight NH...O bonds which range from 2·83 to 2·97 Å. The material crystallizes in the triclinic space group P¯1 with unit cell parametersa = 8·594 Å,b = 7·478 Å,c = 6·915 Å, = 96·9 °, = 95·4 ° and = 85·5 °. The structure was solved by means of the symbolic addition procedure for phase determination.National Academy of Science-National Research Council Postdoctoral Resident Research Associate. 相似文献
9.
Simon G. Bott Alan P. Marchand Sulejman Alihodzic 《Journal of chemical crystallography》1998,28(4):259-266
Crystal structures of four dibromomethylene-functionalized hexa- and heptacyclotetradecane cages are reported. 7-(Dibromomethylene)heptacyclo[6.6.0.02,6.03,13.04,11.05,9.010,14]tetradecane (3): orthorhombic, Pnma, a = 14.744(1), b = 11.237(1), c = 7.4625(7) Å Z = 4; R = 0.0531 for 504 observed reflections. 7,12-Bis(dibromomethylene)heptacyclo[6.6.0.02,6.03,13-04,11 .05,9.010,14]tetradecane (4): monoclinic, I2/a, a = 11.257(1), b = 9.5844(8), c = 13.884(2) Å, = 92.254(8)° Z = 4; R = 0.0413 for 663 observed reflections. 10,14-bis(dibromomethylene)hexacyclo[6.6.0.02,6.03,13.04,11.05,9]tetradecane (6): monoclinic, P21/n, a = 8.118(1), b = 15.273(4), c = 12.826(3) Å, = 104.20(1)° Z = 4; R = 0.0384 for 1392 observed reflections. 14-(dibromomethylene)hexacyclo[6.6.0.02,6.03,13.04,11.05,9]tetradecan-10-one (7): monoclinic, P21/n, a = 8.2879(7), b = 15.273(1), c = 10.0565(9) Å, = 92.271(8)° Z = 4; R = 0.0320 for 1402 observed reflections. The functional groups lead to slight shortening of bond lengths. 相似文献
10.
Zedong Dong Victor G. Young Jr. Eric J. Munson Steve A. Schroeder Indra Prakash David J.W. Grant 《Journal of chemical crystallography》2003,33(10):787-793
The benzene and ethanol solvates of neotame crystallized from solutions of neotame anhydrate in benzene and ethanol, respectively. The crystal structures of the two solvates were determined by single-crystal X-ray diffraction using synchrotron radiation. The benzene solvate crystallizes in the monoclinic space group, P21, Z = 2, with one neotame molecule and one benzene molecule per asymmetric unit. The cell constants are a = 13.060 (6) Å, b = 5.582 (2) Å, c = 17.954 (9) Å, and = 102.079 (15)°. The ethanol solvate crystallizes in the orthorhombic space group, P212121 with Z = 8 (Z = 2). The cell constants are a = 10.047 (4) Å, b = 17.001 (4) Å, and c = 28.948 (7) Å. Intermolecular hydrogen bonding among neotame molecules is evident in the two crystals. The benzene solvate has a nonpolar region containing the benzene molecules, with the benzene rings and alkyl chains of the neotame molecules. 相似文献
11.
N. V. Zubkova D. Yu. Pushcharovsky G. Giester I. V. Pekov A. G. Turchkova N. V. Chukanov E. Tillmanns 《Crystallography Reports》2005,50(3):367-373
The crystal structures of K-and Cs-exchanged forms of zorite were studied by X-ray diffraction and IR spectroscopy: K4.75Na1.82[Ti(Ti0.79Nb0.20)4Si12O34(O,OH)5.2] × 10.62 H2O (sp. gr. Cmmm, R= 0.0481 for 516 independent reflections) and Cs4.34Na1.90[Ti(Ti0.80Nb0.18)4Si12O34(O,OH)5] × 5.37 H2O (sp. gr. Cmmm, R = 0.0285 for 621 independent reflections). Both structures retain the mixed polyhedral framework of zorite: Na6Ti(Ti,Nb)4(Si6O17)2(O,OH)5 × nH2O, where n ~ 11. It is shown that the positions of the atoms located in the cavities of the frameworks of these compounds differ from those in the structures of zorite and its synthetic analogs. 相似文献
12.
Thomas Steiner 《Journal of chemical crystallography》1997,27(11):673-675
The X-ray crystal structure of propargylammonium hexafluorosilicate, 2(C3H6N)+ (SiF6)2?, is determined. The SiF6 anion is involved in N?H...F and C?H...F interactions with eight surrounding cations. This involves two-three-and four-center N?H...F hydrogen bonds, and additional C?H...F interactions with C...F distances down to 2.963(6) Å. The alkynyl C?H donors form only C?H...F interactions of unfavorable geometries. 相似文献
13.
A.G. Pinkus K.K. Klausmeyer R.P. Feazell L.Y.C. Meng T.C. Chang 《Journal of chemical crystallography》2004,34(9):637-640
The crystal structures of 2-chlorobenzophenone (1) and 2,5-dichlorobenzophenone (2) were obtained by single-crystal X-ray diffraction. Crystallization of 1 occurs in the centrosymmetric monoclinic space group P2
1/c (No. 14) with a = 8.2812(8), b = 16.5933(1), c = 7.7599(7); = 98.488(5)° and Z = 4. Crystallization of 2 occurs in the centrosymmetric orthorhombic space group Pbca (No. 61) with a = 16.414(3), b = 7.7896(1), and c = 17.754(4); and Z = 8. Details of the structures and spectroscopic results are presented and discussed. Torsion angles about the carbonyl functionality were found to be outside the previously observed values for unsubstituted benzophenones by greater than 20°. 相似文献
14.
R. K. Rastsvetaeva I. V. Pekov N. V. Chukanov K. A. Rozenberg L. V. Olysych 《Crystallography Reports》2007,52(5):811-818
The high-sodium variety of cancrinite [Si6.3Al5.7O24][Na2(H2O)2][Na5.7(CO3)0.9(SO4)0.1(H2O)0.6] (Kovdor Massif, Kola Peninsula, Russia) and the calcium-containing variety of cancrisilite [Si6.6Al5.4O24][(Na1.2Ca0.4)(H2O)1.6][Na6(CO3)1.3(H2O)1.2] (Khibiny Massif, Kola Peninsula, Russia) are studied. The trigonal unit cell parameters of the crystal structures under investigation are as follows: a = 12.727(4) Å, c = 5.186(2) Å, and space group P3 for the former mineral and a = 12.607(4) Å, c = 5.111(1) Å, and space group P3 for the latter mineral. The reduced symmetry of the new varieties as compared to the symmetry of typical cancrinite and typical cancrisilite is associated with the specific features in the arrangement of the carbonate groups and water molecules in channels. This inference is confirmed by the IR spectroscopic data. 相似文献
15.
Michael P. Du Plessis Tomasz A. Modro Luigi R. Nassimbeni 《Journal of chemical crystallography》1983,13(3):179-189
The crystal structures of the two carboxylic amides C13H10N2O3 (I) and C14H13NO2 (II) have been determined by direct methods and refined by full-matrix least squares. The predominant structural feature is the hydrogen bonding (N-H?O=C) which influences the conformations of both structures. 相似文献
16.
G. D. Andreetti L. Cavalca A. Gaetani Manfredotti C. Pelizzi 《Journal of chemical crystallography》1971,1(3):225-233
The crystal and molecular structures of two polymorphs ofo-bromophenylazocarbamide (C7H6N3OBr) have been determined and refined by Fourier methods, using three-dimensional X-ray data collected at room temperature by photographic techniques. The unit cell parameters are, for the monoclinic modificationa = 25·20(1),b = 5·03(1),c = 14·01(1) Å, β = 105·5(1·0)°,Z = 8, space groupC2/c; for the orthorhombic modification,a= 14·02(1),b = 5·04(1),c = 24·32(3) Å,Z = 8, space groupPca21. In both polymorphs a rather large thermal effect is present, being greater for the orthorhombic phase. Corresponding bond distances and angles are equal in both structures to within 1σ. The double bond is virtually localized in theazo group, so that there is no conjugation between the bromophenyl and the carbamidic groups. NH···O hydrogen bonds link the molecules in ribbons, which are parallel in the monoclinic modification and mutually tilted (76·7 °) in the orthorhombic structure. 相似文献
17.
N. V. Zubkova I. V. Pekov A. G. Turchkova D. Yu. Pushcharovskiĭ S. Merlino M. Pasero N. V. Chukanov 《Crystallography Reports》2007,52(1):65-70
The crystal structures of potassium-exchanged forms of catapleiite and hilairite of the compositions (K0.49Ca0.42Na0.26)ZrSi3O9 · 2[(H2O)0.8(H3O)0.2] and K0.51ZrSi3O9 · 3[(H2O)0.5K0.27(H3O)0.23], respectively, were studied by X-ray diffraction and IR spectroscopy. Both structures retain the heteropolyhedral frameworks of the parent minerals formed by Zr octahedra and Si tetrahedra. The K cations occupy different positions in these minerals. In K-exchanged catapleiite, K cations are located only in the position occupied by Na in the structure of the parent mineral. In the K-exchanged form of hilairite, K cations are not only involved in the Na position but also partially occupy the H2O position. 相似文献
18.
Mark C. Elliott K.M. Abdul Malik Eve Williams 《Journal of chemical crystallography》2004,34(6):371-381
Crystal structural studies of two new biisoquinoline derivatives, a neutral compound C20H24N2 (3) and a salt C18H21N2
+C10H14BrO4S– H2O (4) are described and discussed. Compound 3 crystallizes in the monoclinic space group P2
1/c, with a = 11.039(2), b = 7.791(2), c = 19.001(4) Å, = 104.31(3)°, and Z = 4. Compound 4 crystallizes in the monoclinic space group P2
1, with a = 12.0021(3), b = 8.9189(2), c = 12.8685(4) Å, = 100.7600(10)°, and Z = 2. The absolute stereochemistry of 4 in the solid state has been determined. The biisoquinoline rings in both compounds adopt twist-boat conformations with significant deviations from ideal geometry. The two heterocyclic rings in each species are oriented so that they are not overlayed with each other and the phenyl rings are oppositely directed. The cations and the anions in 4 are linked together through an elaborate system of hydrogen bonding involving the water molecule. 相似文献
19.
Eric W. Reinheimer Katherine A. Kantardjieff Steven R. Herron Christopher G. Tisserat Joe A. Casalnuovo 《Journal of chemical crystallography》2003,33(5-6):503-514
The crystal structures of four diphosphinated Group 6 Fischer alkoxy carbenes with the compositions fac-(dppe)(CO)3M–C(OR)(R) (R = Me, R = Et, M = Cr, 1; R = Ph, R = Me, M = Cr, 2; R = Me, R = Me, M = W, 3; R/OR = 3-methyl-2-oxacyclopentylidenyl, M = Cr, 4) have been determined at 243 K. Compound 1 crystallizes in the monoclinic system, space group P21/c with a = 11.2243(11) Å, b = 18.5998(18) Å, c = 15.1260(15) Å, = 107.056(4), V = 3019.0(5) Å3, and Z = 4. Compound 2 crystallizes in the monoclinic system, space group P21/c with a = 11.8102(9) Å, b = 18.3152(14) Å, c = 15.0262(12) Å, = 93.753(3), V = 3243.3(4) Å3, and Z = 4. Compound 3 crystallizes in the monoclinic system, space group P21/c with a = 11.3458(6) Å, b = 18.5772(9) Å, c = 15.3883(8) Å, = 108.576(6), V = 3074.5(3) Å3, and Z = 4. Compound 4 crystallizes in the orthorhombic system, space group Pna21 with a = 22.6509(14) Å, b = 9.8118(6) Å, c = 13.7507(8) Å, V = 3056.0(3) Å3, and Z = 4. Steric repulsions with the dppe ligand favor a conformation with the alkoxy moiety directed toward the dppe backbone, in an E geometry, in 1–4. 相似文献
20.
V. Ferretti P. Gilli V. Bertolasi G. Spalluto G. Gilli 《Journal of chemical crystallography》1993,23(3):195-201
(3(Z),4,6a,9a,9b)-(±)-3a,4,6a,7,8,9,9a,9b-octahydro-4,7,7, 9b-tetramethyl-3a-[3-(methoxymethyloxy)-3-methyl-1-butenyl]-5H-naphto[1,8-de]-1,3-dioxin-6-one (I), C22H36O5,M
r=378.51, monoclinic,P21/n,a=6.330(1),b=14.576(2),c=22.837(2)Å,=93.04(1)°,V=2104.1(2)Å3,Z=4,D
c=1.19 Mg/m3, (MoK)=0.71069Å,=0.8 cm–1,F(000)=832,T=298 K,R=0.054 for 1971 observed reflections; (7a,10a,10b,12)-(±)-7a,9, 10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6,-de][1,3,2]-benzodioxin-11-one (II), C20H29O4,M
r=334.5, triclinic,P-1,a=10.595(2),b=12.152(1),c=8.073(1)Å,=106.53(1),=105.65(1), =66.29(1)°,V=897.9(2)Å3,Z=2,D
c=1.24 Mg/m3, (MoK)=0.71069Å,=0.8 cm–1,F(000)=362,T=298 K,R=0.046 for 2848 observed reflections; (7a,10a,10b,12, 12a)-(±)-7a,9,10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6-de][1,3,2]-benzodioxin-11, 12-diol (III), C20H32O5 (two molecules in the asymmetric unit),M
r=352.2, triclinic,P-1,a=12.948(3),b=13.615(3),c=12.197(4)Å,=101.16(2),=111.88(2), =69.48(2)°,V=1863.8(9)Å3,Z=2,D
C=1.26 Mg/m3,(MoK)=0.71069 Å,=0.8 cm–1,F(000)=768,T=298 K,R=0.060 for 4570 observed reflections; 4-acetoxy-4-[[(4a,5,8a)-(±)-hexahydro-4a,6,6-trimethyl-4H-1,3-benzodioxin-4-one]-5-yl]butan-2-one (IV), C17H26O6,M
r=326.4, monoclinic,P21/c,a=10.495(2),b=12.050(2),c=14.216(2)Å,=108.51(1)°,V=1704.8(5)Å3,Z=4,D
c=1.27 Mg/m3,(MoK)=0.71069 Å,=0.9 cm–1,F(000)=704,T=298 K,R=0.049 for2455 observed reflections; (3a,4,5,6,6a,9a,9b)-(±)-4,5-epoxy-decahydro-3, 3a-dihydroxy-2-ethoxy-4,7,7,9b-tetramethyl-naphto-[1,8-bc]-pyran-6-ol-acetate (V), C20H32O7,M
r=383.5, monoclinic,C2/c,a=10.353(2),b=17.975(3),c=21.188(3)Å,=91.29(1)°,V=3942(1)Å3,Z=8,D
c=1.29 Mg/m3,(MoK)=0.71069 Å,=0.8 cm–1,F(000)=1664,T=298 K,R=0.051 for 2120 observed reflections. We report here the complete structures of four decalin derivatives (compoundsI, II, III, V) and one related compound (compoundIV) synthetized in order to find an efficient synthetic approach for the natural productforskolin. 相似文献