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1.
The title compound, 1-(2,3-dideoxy-3-fluoro--d-erythro pentofuranos-1-yl)-5-chlorocytosine, crystallises in the orthorhombic space groupP212121 witha=5.142(1),b=14.177(2),c=15.721(2) Å,Z=4. The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares method to a finalR value of 0.031 for 1629 unique observed reflections. The N-glycosidic torsion angle is –156.1(2)° and the sugar moiety is anti to the cytosine base. The sugar pucker is 2 3 T withP=178.2(1)° and=31(1)°. The atom 05 is in a +sc conformation with respect to the furanose ring. The molecular packing in the crystal is stabilized by N-HN, N-HO, O-HO hydrogen bonds and C-HO close contacts.  相似文献   

2.
The title compound belongs to the triclinic space groupP¯1,a= 8.189 Å,b = 9.863 Å,c = 10.726 Å, = 69.93 °, = 68.62 °, = 73.66 °, andZ = 2. The structure was refined on 1337 observed reflections to anR factor of 0.042. The crystals contain [adeninato(CH3Hg)2]+ complex cations in which mercury is linearly bonded to N(7) and N(9) of a deprotonated adenine ring. Centrosymmetrically related complex cations are paired via two N(6)-H(6) N(l) hydrogen bonds. Those planar units are stacked in the crystal with a distance of 3.4 Å between rings. The water molecule and the ClO4 -ion are involved in hydrogen bonding and HgO contacts. This structure identifies N(7) as the best residual coordination site after H(9) has been substituted by CH3Hg.  相似文献   

3.
Naphazoline·HNO3 (1): C14H15N3O3,M r =273.3, crystallizes in the orthorhombic space group Pbca(Z=8) witha=12.028(1),b=14.408(2) andc=15.894(2) Å,V=2754.4 Å3,D x =1.318 g cm–3,=0.70 mm–1, (CuK)=1.54178 Å,F(000)=1152. FinalR=0.092 andwR=0.088 for 1348 observed reflections collected on a diffractometer. The structure was solved with direct methods, it shows two distinct positions of the naphthyl group with populations about 0.5, which differ by a 180 rotation. As in other arylmethyl-2-imidazolines, the imidazoline ring is approximately perpendicular to the aromatic ring. The molecules are linked by two hydrogen bonds N(3)-HO (nitrate anion)H-N(1) into infinite chains running along the 21 axis in the [100] direction. Tymazoline·HC1·H2O (2): C14H23ClN2O2,M r =286.8, crystallizes in the monoclinic space groupP21/n (Z=4) witha=8.136(1),b=10.015(1),c=18.601(1) Å and,=97.20(1)°,V=1503.7 Å3 D x =1.266 g cm–3,=2.27 mm–1, (CuK)=1.54178 Å,F(000)=636. FinalR=0.115 andwR=0.119 for 3073 observed reflections collected on a diffractometer. The structure was solved with direct methods. Unlike other aryloxymethyl-2-imidazolines, the molecule is almost planar with an angle of 12.8(2)° between the two rings. Hydrogen bonding networks consist of N(1)-HO (water)ClH-N(3) chains joined by an additional link O(water)-HCl between chains running in opposite directions.  相似文献   

4.
The title compound is C19H18O4·1/2 CH3OH, triclinic,P¯1,a=9.891(2),b=13.273(4),c=13.860(4) Å,a=66.47(2),=86.91(2), and =85.59(2)°. The structure was solved by direct methods and refined by least-squares techniques to anR factor of 0.082 for 2282 observed reflections. The X-ray structure uniquely resolves the one remaining ambiguity, namely the assignment of the correct structure4. There are two crystallographically independent molecules (A and B) and one disordered methanol molecule. Both molecular skeletons show small distortions from planarity with inclinations of 1.7 and 4.0° between the outermost rings A/C in molecules A and B, respectively. Intramolecular hydrogen bonds of the form O(3A)-HO(2A) and O(3B)-HO(2B) are observed in molecules A and B, respectively. The molecules are linked by pairs of O(3A)-HO(2B) and O(3B)-HO(2A) hydrogen bonds. The dimerlike structures are stabilized by intermolecular C-HO interactions and van der Waals forces.  相似文献   

5.
The crystal structure of the title compound has been determined from three-dimensional X-ray diffraction data, and refined by full-matrix least-squares techniques. The crystals belong to the monoclinic space groupP21/c, witha = 8.849(4),b = 13.798(5),c = 7.943(4) Å, = 102.98(3) °, andD x = 1.85g cm–3 forZ = 4. The finalR factor for 1283 observed reflections is 0.046. The aluminum atom is bonded to the nitrogen atom of the thiocyanate ligand, where the Al-N bond length is 1.94(1) Å. The SCN is linear, and the CN-Al angle is 175(1) °. The cesium ion exhibits four contacts less than 3.60 Å: Cs C(thiocyanate) = 3.39(1) Å, Cs C(methyl) = 3.52(1) Å, Cs C.(methyl) = 3.56(1) Å, and Cs N = 3.575(9) Å. The closest Cs S is 3.772(3) Å.  相似文献   

6.
The title compound 1-(1,3-dimethyl-5-chloropyrazol-4-carbonyl)-3-(2-chlorophenyl)-5-amino-4-cyanopyrazole (C16H12Cl2N6O) has been synthesized and characterized by X-ray diffraction: Triclinic, space group P1, with a = 8.6712(8) Å, b = 9.5091(10) Å, c = 11.2170(11) Å = 71.531(2)°, = 84.683(2)°, = 74.099(2)° Z = 2; V = 843.7(14) Å3. C(10), O(1), C(11), and N(2) atoms are coplanar with the average deviation of 0.0071 Å, which form 11.03° and 43.93° dihedral angles with pyrazole planes (I) and (II), respectively.  相似文献   

7.
The X-ray diffraction structure of (RS)-5,6-dihydro-7,8-dimethoxy-5-methyl-6-(2-oxopropyl)-(2,3-methylenedioxyphenyl)-[c]-phenanthridine ((RS)-6-acetonyldihydrochelerythrine), isolated as an artifact from Bocconia Arborea, is reported. This compound crystallizes as orthorhombic system, space group Pna21, with a = 13.216(2) Å, b = 7.6547(10) Å, c = 20.096(3) Å. The phenanthridine central ring presents a distorted boat conformation, which gives rise to two planes with 21.30° between them. The acetonyl group at the six position forms weak C — H O and C — H -ring interactions. The title compound was completely characterized in solution by 1H and 13C and 2D NMR experiments.  相似文献   

8.
The crystal structure of the title compound, tetrabutylammonium bis(2-thioxo-1,3-dithiole-4,5-dithiolato)nickelate(III), [N(C4H9)4][Ni(C3S5)2], is the fourth known phase of this polymorphous compound. It is monoclinic space group P21/c, with a = 20.040(2) Å, b = 13.1151(17) Å, c = 12.1093(15) Å, = 105.456(15)°, and V = 3067.5(6) Å3 with Z = 4, for D calc = 1.503 g cm–3. The [Ni(dmit)2] anion packing arrangement consists of arrays of side-on touching anions and these arrays are connected via head-to-tail close S S contacts.  相似文献   

9.
A novel compound catena-(-CrO4-O,O)[Ni(L1)Ni(L2)] 3H2O (1) (L1 = 3,5,10,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane and L2 = 2,5,9,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized for the first time and structurally characterized. 1 crystallizes in the triclinic space group P with a = 9.623(1), b = 10.084(1), c = 12.723 (3) Å, = 66.74(2), = 75.20(1), = 72.02(1)°, V = 1066.2(3) Å3, and Z = 2. The coordination environment around the Ni(II) ions is an axially elongated octahedron with the secondary amines of the isomeric ligands and two oxygen atoms of [CrO4]2–.  相似文献   

10.
The title compound C9H11NO2 is triclinic, space group P¯1, with the cell dimensionsa=7.022(1),b=7.476(2),c=8.957 (1) Å,=87.02(2),=110.88(1),=99.10(1)°,V=433.8(4) Å3,Z=2,M r =165.2,Do=1.27,Dx=1.26 mg/m3,F(000)=176,T=293 K,R=0.057 for 939 observed reflections. The molecules are packed as centrosymmetric hydrogen bonded dimers with an O-HO distance of 2.626(3) Å. The COOH group is rotated by 1.7(1)° about the exocyclic C(1)-C(7) bond out of the benzene ring plane. The molecules lie on (0 2-1) plane for which thed value is found to be 3.378 Å which is very close to the mean separation between the parallel packed benezene rings [3.347(4) Å]. The entire molecule is planar except for the two methyl groups attached to the nitrogen atom. The N atom is free from any binding of either type C-HN or O-HN.N. C. L. Communication No. 4699.  相似文献   

11.
The crystal structure of TeCl2(C7H7O)(C7H11O2) has been determined from three dimensional, single crystal X-ray diffraction data. It crystallizes in the monoclinic space group C2/c with the lattice constantsa=24.551(5),b=11.435(2),c=12.368(2)Å,=97.33(1)° andZ=8,D X=1.67 g cm–3. Final least-squares refinement based on 3023 independent observed reflections yieldedR=0.026. The Teiv ion is in a trigonal bipyramidal configuration with its lone pair of electrons at one of the equatorial positions. Distances and angles are: Te-Cl=2.495(1), 2.517(1); Te-C=2.134(3), 2.106(3)(aryl)Å; Cl-Te-Cl=173.45(4), Cl-Te-C=88.11(9), 88.60(9), 88.72(9), 86.06(9); C-Te-C=96.5(1)°. There are two secondary bonds to the tellurium: TeCl=3.824(1) and TeO(2)=3.006(1)Å. The methyl group to the carbonyl oxygen and the aryltelluro moiety exhibit atrans 2,4 relationship.  相似文献   

12.
The crystal and molecular structure of the hexaazamacrocycle C24H14N6 has been determined from X-ray diffractometer data. The crystals are monoclinic, space groupP21/c witha = 4.416(1),b = 9.972(4),c = 18.955(12) Å, = 95.48(4) °, andZ = 2. The structure was derived from 536 reflections using direct and Fourier methods and was refined by least squares toR = 0.038. The polar molecules form stacks along thea axis with an inclination of 68 ° and an interplanar distance of 3.32 Å. The size of the central hole of the molecule is defined by the diagonal distances N(2) N(2) = 3.681(10) and N(3) N(3) = 3.771(9) Å of theo-phenanthroline nitrogens. This is too small to accommodate Pd2+ or Pt2+ in the hole.  相似文献   

13.
The structure of the nondeuterated and deuterated complexes of 3,5-dimethylpyridine with 3,5-dinitrobenzoic acid in a stoichiometric ratio 12 have been determined by X-ray diffraction methods. The crystals of the nondeuterated complex are triclinic, space groupP¯1 witha=9.409(9),b=10.813(7),c=12.310(7)Å,a=95.75(5),=108.17(7), =91.46(7)° andZ=2. The crystals of the deuterated complex are monoclinic, space groupP21/c, witha=11.680(6),b=8.451(4),c=24.382(9)Å,=102.94(4)° andZ=4. Both structures have been solved by direct methods and refined toR=0.035 for 2235 and toR=0.044 for 1938 independent reflections for nondeuterated and deuterated crystal, respectively. The structures consist of 3,5-dimethylpyridinium cations and hydrogen (or deuterium) bis(3,5-dinitrobenzoate) anions. The N(1)+-H(N1)O(1), O(7)-H(7)O(2), N(1)+-D(1)O(l) and O(7)-D(7)O(2) bond lengths are 2.644(4), 2.499(3), 2.739(5), and 2.526(5)Å, respectively. The IR spectra of both complexes within the proton (or deuteron) absorption range have been studied.  相似文献   

14.
The crystals of the title compound (C12H13NO4) are orthorhombic,P212121 witha=8.541(3),b=10.988(1), andc=11.912(1) Å.M r =235.24, mp 427 K,Z=4,D x =1.348 Mg m–3, (MoK=0.71069 Å, =0.11 mm–1,T=293 K. The structure was solved by direct methods and refined by full-matrixs least squares to a finalR=0.028 for 1180 observed reflections. The molecules are connected by N-HO (ring carbonyl) intermolecular HO hydrogen bonds of 2.24(2) Å. The 4-oxo-1,3-dioxane ring is in a slightly distorted sofa conformation with a C s 1 asymmetry parameter of 3.6(2)° and the 5-methyl substituent in a pseudoaxial position. The benzoyl oxygen is turned toward the ring, resulting in a close OH(C6) contact of 2.45(2) Å.  相似文献   

15.
A novel oxovanadium(IV) complex with tridentate schiff base and bidentate phenanthroline ligands, VO(o-van)(phen) 2H2O[o-van-gly: o-vanillin-glycine; phen: phenanthroline], was synthesized and characterized by elemental analysis, IR and UV-vis spectra. The crystal structure was determined by X-ray single crystal diffraction analysis. The crystal of title complex (C22H21N3O7V, Mw = 490.36) belongs to triclinic, space group P-1 with the following crystallographic parameters: a = 9.247(3) Å, b = 10.125(4) Å, c = 13.100(5) Å, = 106.343(6), = 96.042(7), = 101.726(7), V = 1135.0(7) Å3, Z = 2, Dc = 1.435 Mg m–3, (MoK = 0.485 mm–1, F(000) = 506, and final R1 = 0.0779, wR2 = 0.1598 for observed reflections 1606 (I > 2(I)). V(IV) is six-coordinate with three oxygen atoms and three nitrogen atoms in a distorted octahedral geometry. The complex forms a 3-D network via – stacking and hydrogen bonds.  相似文献   

16.
A series of cage-annulated sulfur-containing crown ethers and cryptands have been synthesized as possible specific metal host systems. The synthesis and structures of seven compounds are described, including a thiacryptand complex with Hg(II). The trishomocubane cage is essentially spherical except for a methylene group, which imparts no steric restrictions, and two disordered superimposed orientations occur in most structures. This superposition of four- and five-membered rings usually cannot be resolved into separate entities, resulting in distorted distances, angles, and thermal parameters for the cage. (3) I41 cd, a = 13.207(3) Å, b = 13.207(3) Å, c = 35.876(12) Å; (10) C2, a = 14.551(2) Å, b = 10.028(1) Å, c = 10.491(1) Å, = 107.108(2)°; (14) P21/n, a = 10.6277(8) Å, b = 9.8488(7) Å, c = 21.822(2) Å, = 97.945(2)°; (19) P21/c, a = 15.381(3) Å, b = 6.667(1) Å, c = 18.158(3) Å, = 94.838(4)°; (25) C2/c, a = 34.386(4) Å, b = 11.318(1) Å, c = 13.409(2) Å, = 110.044(2)°; (28) , a = 10.4487(8) Å, b = 11.5677(9) Å, c = 13.354(1) Å, = 71.042(1)°, = 87.344(1)°, = 65.839(1)°; (29) P21/c, a = 10.8138(5) Å, b = 16.4949(8) Å, c = 22.054(1) Å, = 96.087(1)°.  相似文献   

17.
The tris-2-chloro and 2-bromotribenzylamines are prepared from aqueous ammonia and 2-chlorobenzyl chloride and 2-bromobenzyl bromide, respectively, in ethanol. Recrystallization yielded colorless cubes of each product. The crystal structures are each solved in space group P , and are isostructural. The tris-2-chloro compound, 1, has a = 7.4226(5) Å, b = 9.0825(7) Å, c = 14.529(1) Å, = 78.279(1), = 82.389(1), = 84.661(1), and V = 948.41(12) Å3 with Z = 2, and dcalc = 1.368 Mg/m3. The tris-2-bromo analog, 2, has a = 7.6569(11) Å, b = 9.0922(13) Å, c = 14.614(2) Å, = 79.286(2), = 81.777(2), = 85.401(2), and V = 987.9(2) Å3 with Z = 2, and dcalc = 1.762 Mg/m3. Lithium–halogen exchange experiments conducted in tetrahydrofuran at –78C using n-butyl lithium revealed that no exchange occurred for the tris-2-chloro compound, but did occur for the tris-2-bromo analog to yield tribenzylamine upon quench and work-up.  相似文献   

18.
The title compound has been synthesized, and characterized by means of X-ray, magnetic, and IR-spectroscopic measurements.The crystals of Cu(DPhP)2(H2O)2(DPhP=diphenylphosphate) are monoclinic, space groupI2/c witha=24.126(6),b=8.510(2),c=12.333(3) Å,=90.73(5)° andZ=4. The structure was solved by the heavy-atom technique, and refined by full-matrix least-squares calculations to a finalR of 0.040 for 1494 reflections.The complex is centrosymmetric, and the Cu atom at a center of symmetry is four-fold coordinated with two oxygen atoms from two phosphate groups and two water molecules. The coordination about the Cu atom is square-planar, with Cu-O and Cu-O(W) distances 1.926(3) and 1.912(3) Å, respectively.The O(2) phosphate oxygen is an acceptor of two H bonds; one of them is an intramolecular O(W)-H(2)O(2) of 2.714(4) Å, and the other is an intermolecularO(W)-H(1)O(2i) of 2.667(4) Å. Their presence is also deduced from the IR spectrum of this compound at 3250 and 3000 cm–1, respectively.The calculated magnetic moment value of 1.92 B.M. corresponds to that of the monomeric copper(II) complexes including those of some alkyl phosphates.  相似文献   

19.
The crystal structure of the binuclear tetraiminediphenolate diiron(II) macrocyclic complex [Fe2(tidf)(CH3OH)4](ClO4)2 (tidf = tetraiminediphenolate ligand) is presented. The molecular structure (monoclinic, space group C2/c, Z = 4, a = 20.6903(14)Å, b = 11.0827(11) Å, c = 16.0494(15) Å, = 99.911(6) shows two iron(II) cores occupying distorted octahedral geometries with four methanol molecules bound axially. Main equatorial bond distances are 2.050(3) Å for Fe—O1 and 2.067(4) Å for Fe—N1 with a Fe Fe distance of 3.108(1) Å. Contrasting to the monoiron complex the macrocycle does not adopt a bent conformation being nearly coplanar with the maximum deviation from the least-squares plane of 0.18 Å.  相似文献   

20.
Crystal and molecular structures for aryl- and benzyl-substituted 3-hydroxy-3,4-dihydroisobenzopyran-1-one are described. For the 4,4-dimethyl derivative, two monoclinic modifications are produced on sublimation: (1) P21/c, a = 23.668(6) Å b = 11.749(4) Å c = 7.215(2) Å = 96.70(2); V = 1992.6(10) Å3; (2) P21/c, a = 11.509(4) Å, b = 12.429(4) Å, c = 6.933(2) Å, = 91.12(3), V = 991.6(6) Å. In both, hydroxy groups are pseudoaxial, and molecules form dimeric complementary but noncooperative hydrogen bonds. In the 6-methoxy derivative (3), P21/c; a = 14.185(7) Å b = 4.105(4) Å c = 15.598(13) Å = 98.59(6); V = 898.1(10) Å3, the hydroxy group is pseudoequatorial, and the intermolecular hydrogen bonding forms infinite chains. In the 4,4-dimethyl-7-nitro derivative (4), C2/c, a = 19.365(4), b = 8.425(2), c = 13.464(4), = 92.62(2), V = 2194.2(7) Å3, the hydroxy group is pseudoaxial, and the intermolecular hydrogen bonding forms chains. Compared to the unmethylated compounds, the interbond angles within the ring at the dimethylated carbon are contracted.  相似文献   

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