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1.
A method for constructing a 2D quasi-periodic Rauzy tiling Til as a section of some 3D periodic tiling Til 3D is considered. The translation lattice of the tiling Til 3D and its connectivity graph are constructed using the discrete modeling of packings. The calculation of the layer-by-layer growth polyhedron for the tiling Til 3D made it possible to estimate from upper the shape of a growth polygon for the tiling Til. As a result, the growth shape in six out of eight growth sectors has been rigorously proven. A set of quasi-periodic tilings (locally indistinguishable from the Rauzy tiling Til), including seven centrosymmetric tilings, has been obtained.  相似文献   

2.
The crystal structure of 6,13-bis-(N,N-dimethylcarbamoyl)thioquinanthrene 3 has been determined as monoclinic, with space group P2(1)/c with lattice parameters a = 10.044(2) Å, b = 21.385(4) Å, c = 10.889(3) Å, = 102.92(3)°, Z = 4 and Dcalc = 1.342 Mg/m3. The middle 1,4-dithiin ring in the title compound 3, C24H20N4O2S2 is in a boat conformation with the dihedral angle between the planes of the aromatic rings 132.45(8)°.  相似文献   

3.

Abstract  

The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid (C14H10N2O7, M r  = 318) was synthesized and its structure was characterized by elemental analysis, 1H NMR and IR spectra. The single crystal of the title compound (C14H14N2O9, M r  = 354.27) was cultured and its structure was determined by single crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 14.3859(19), b = 12.5835(18), c = 8.6934(15) ?, β = 102.824(2)°, V = 1534.5(4) ?3, Z = 4, D c  = 1.534 g cm−3, μ(Mo ) = 0.131 mm−1, F(000) = 736. The final refinement gave R = 0.0652, wR(F 2) = 0.1239 for 2,703 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the asymmetric unit of the title compound contains one N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid molecule and two water molecules. One of the two water molecules is disordered. The phthalimide group is essentially planar. The crystal structure of the title compound is stabilized by N–H…O and O–H…O hydrogen bonds interactions. The compound N-(N-acetic acid-yl-phthalimide-5-yl) maleamic acid possesses moderate antibacterial activity.  相似文献   

4.
Sideroxol (1), a kaurane diterpene which has the ent-7α,18-dihydroxy-15β,16β-epoxykaurane structure (MW = 320.47, C20H32O3) was obtained from the acetone extract of Sideritis leptoclada plant as well as from some other Sideritis species. It crystallizes in the orthorhombic space group P21, 21, 21 with a = 10.967(3), b = 24.555(5), c = 6.372(4) Å, Dc = 1.240 g cm−3, Z = 4, and refines to R = 0.065 for 721 independent reflections. The skeleton consists of three fused six-membered rings and a five-membered ring with fused epoxide. The six membered rings exhibited slightly distorted chair conformation. In addition to sideroxol, two kaurane and five kaurene diterpenes were isolated from the hexane and acetone extracts of the studied plant.  相似文献   

5.

Abstract  

Molecular and crystal structure of 4-[(p-N,N-dimethylamino)benzylidene]-2-phenyloxazol-5-one, C18H16N2O2, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 12.1704(23) ?, b = 3.9810(5) ?, c = 30.9603(56) ?, β = 101.176(15)°, Z = 4, D x = 1.32 g/cm3, μ(Mo Kα) = 0.087 mm−1, and space group is P121/c1. The structure was solved by direct methods and refined to a final R = 0.047 for 3166 reflections with I > 2σ(I). The crystal structure is stabilized by C–H⋯O and C–H⋯N type intra-molecular, C–H⋯O type inter-molecular interactions. To enlighten the flexibility and the geometric isomerism (E or Z) of the title compound, the selected torsion angle is varied from −180 to 180° in every 10° separately and molecular energy profile is calculated and analyzed.  相似文献   

6.
Refluxing 2,3-dichloromaleic anhydride with p-anisidine in benzene with water removal gives the condensation product 2,3-dichloro-N-(p-MeOC6H4)maleimide (1) 75% yield. This new maleimide compound reacts with added ethanethiol in the presence of Et3N or DBU to furnish the bidentate sulfide ligand 2,3-bis(ethylthio)-N-(p-MeOC6H4)maleimide (2) in 85% yield. Each product has been characterized in solution by IR, NMR, and UV-vis spectroscopies, and the solid-state structure of 2,3-bis(ethylthio)-N-(p-MeOC6H4)maleimide was unequivocally established by single-crystal X-ray diffraction analysis. 2,3-bis(Ethylthio)-N-(p-MeOC6H4)maleimide crystallizes in the monoclinic space group C2/c, a = 20.035(3)Å, b = 9.188(1)Å, c = 16.887(2)Å, = 93.696(2)°, V = 3102.3(8)Å3, Z = 8, and Dcalcd = 1.385 mg/m3; R = 0.0268, Rw = 0.0676 for 2025 reflections with I > 2 (I). The nature of the LUMO in 2,3-bis(ethylthio)-N-(p-MeOC6H4)maleimide (2) has been determined by extended Hückel molecular orbital calculations, and these data are discussed relative to the cyclic voltammetry results and other structurally relevant compounds prepared in our labs.  相似文献   

7.
Abstract The crystal structures of four bis-phenols are reported to substantiate the fact that the weak interactions play a major role in the crystal packing of bis-phenols. The reaction of 2,4-dimethylphenol with aldehydes such as 2-naphthaldehyde, terephthaldehyde in the presence of trifluoracetic acid gave 2-[bis(2-hydroxy 3,5-dimethylphenyl)methyl]naphthalene (1) and 4-[bis(2-hydroxy 3,5-dimethylphenyl) methyl]benzaldehyde (2), respectively. The 2-[bis-(2-hydroxy 3,5-dimethylphenyl)-methyl]naphthalene (1) crystallizes in orthorhombic, Pbca, a = 11.905(3) ?, b = 18.788(5) ?, c = 18.894(5) ?, 4-[bis(2-hydroxy 3,5-dimethylphenyl)methyl] benzaldehyde (2) in monoclinic, Cc, a = 8.880(3) ?, b = 16.394(7) ?, c = 13.700(5) ?, γ = 104.542(2)°. The reaction of 2-nitrobenzaldehyde with 2,4-dimethylphenol gave 2-benzo[c] isoxazo-3-yl 4,6-dimethylphenol (3) and its crystal parameters are orthorhombic, P212121, a = 7.737(6) ?, b = 11.885(9) ?, c = 13.336(8) ?. The reaction of 2,6-dimethylphenol with 4-nitrobenzaldehyde and 2-chlorobenzaldehyde gave bis(4-hydroxy 3,5-dimethylphenyl)(4-nitrophenyl)methane (4) and bis(4-hydroxy 3,5-dimethylphenyl)(2-chlorophenyl)methane (5), respectively. The bis(4-hydroxy 3,5dimethylphenyl)(4-nitrophenyl)methane (4) crystallizes in monoclinic, C2/c, a = 25.921(1) ?, b = 12.202(4) ?, c = 15.6084(7) ?, β = 122.172(4)°, and bis(4-hydroxy 3,5-dimethylphenyl) (2-chlorophenyl)methane crystallizes as acetonitrile solvate (5) in triclinic, P-1, a = 12.314(3) ?, b = 14.111(3) ?, c = 15.078(5) ?, α = 98.268(2)°, β = 111.268(2)°, γ = 114.304(1)˚. The unit cell of 5 contains two pairs of crystallographically unsymmetric molecules of bis-phenols. Index abstract The crystal structures of four bis-phenols are reported to substantiate the fact that the weak interactions plays a major role in crystal packing and can induce symmetry non-equivalence among bis-phenols in unit cell of bis-phenols.   相似文献   

8.
Double phosphates of zirconium and metals with an oxidation degree of +2 of the composition M0.5Zr2(PO4)3 (M = Mg, Ca, Mn, Co, Ni, Cu, Zn, Sr, Cd, and Ba) are synthesized and characterized by X-ray diffraction methods and IR spectroscopy. The crystal structures of all the compounds are based on three-dimensional frameworks of corner-sharing PO4-tetrahedra and ZrO6-octahedra. Phosphates with large Cd2+, Ca2+, Sr2+, and Ba2+ cations octahedrally coordinated with oxygen atoms form rhombohedral structures (space group R3), whereas phosphates with small tetrahedrally coordinated Mg2+, Ni2+, Cu2+, Co2+, Zn 2+, and Mn2+-cations are monoclinic (space group P21/n). The effect of various structure-forming factors on the M0.5Zr2(PO4)3 compounds with a common structural motif but different symmetries are discussed.  相似文献   

9.

Abstract  

N6-methyl mucronatine (C8H12N5O) has been isolated from a dictyoceratid sponge collected in South East Queensland. The solid state structure of the new metabolite (I) was confirmed by X-ray crystallography, while an NMR study in d 4-MeOH reveals the presence of a minor tautomer identified as (II).  相似文献   

10.
Abstract  Synthesis and X-ray structural determination of three phosphorus compounds are reported. (3b) is monoclinic P2(1)/c with a = 11.852(1), b = 12.825(1), c = 12.445(1) ?, β = 103.693(1)o; (4a) and (4b) are monoclinic P2(1)/n with a = 12.1422(16), b = 9.0860(12), c = 14.845(2) ?, β = 96.498(3)o for (4a), and a = 12.2714(16), b = 9.2812(12), c = 14.800(2) ?, β = 97.176(2)o for (4b). They all exhibit distorted tetrahedral geometry about the P atom. Ph2P(X)NHC7H7 (X=S (4a) and X=Se (4b)) show typical P–S and P–Se double bond distances and P–N single bonds, while P–S bond in 1-Ad2P(S)Cl (3b) is comparable to P–S single bonded probably due to the largeness of 1-adamantyl groups. Graphical Abstract  Synthesis and X-ray structural determination of 1-Ad2P(S)Cl (3b), Ph2P(S)NHC7H7 (4a) and Ph2P(Se)NHC7H7 (4b) are reported.   相似文献   

11.
A new method is proposed for the computer analysis of crystal structures of complex intermetallic compounds (with more than 1000 atoms per unit cell) using a developed algorithm of the complete decomposition of the 3D graph of the structure into nanocluster substructures. This method has been implemented in the TOPOS software package and approved successfully in an analysis of the complex Cu3Cd4 structure (Samson phase). Cu3Cd4 structure models were used to establish a structural relationship between nanoclusters in this intermetallic compound and nanoclusters in other complex crystal structures: ZrZn22, Ru7Mg44, NaCd2, and Mg2Al3.  相似文献   

12.
Abstract Details of the synthesis of the E isomer of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylonitrile, and the X-ray crystal structures of both the E and Z isomers of this compound are presented. The E isomer crystallizes in the P21/c space group with cell parameters, a = 8.5659(17) ?, b = 16.399(3) ?, c = 11.224(2) ?, α = 90°, β = 95.27(3)°, γ = 90°and Z = 4. The Z isomer crystallizes in the Pca21 space group with cell parameters, a = 4.1223(8) ?, b = 19.113(4) ?, c = 19.453(4) ?, α = 90°, β = 90°, γ = 90° and Z = 4. Index Abstract Synthesis of E isomer and X-ray crystal structure determination of both E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylonitrile are presented.   相似文献   

13.

Abstract  

The unstable crystals of triammonium fac-trichloridotrioxidorhenate(VII) chloride have been obtained from ammonium rhenate(VII) solution in concentrated hydrochloric acid. The crystal structure consists of fac-trichloridotrioxidorhenate(VII) anions, chloride anions and ammonium cations. Each fac-trichloridotrioxidorhenate(VII) anion and each chloride anion lies in special position of 3m site symmetry (cell parameters: a = 9.026(3) Å; c = 7.690(4) Å; space group: P63 mc). The ammonium cation lies in special position of m site symmetry. The following anion geometrical parameters of the fac-trichloridotrioxidorhenate(VII) anion have been obtained: Re–O bond length of 1.720(2) Å, Re–Cl bond length of 2.5428(9) Å, the bond angles: O–Re–O of 103.5(1)° and Cl–Re–Cl of 79.8(1)°.  相似文献   

14.

Abstract  

o-[(Phenyl/p-methoxyphenyl)carbamoyl]benzene sulfonamides were synthesized in a straightforward manner utilizing directly saccharin and aniline/p-anisidine as starting material and their crystal structures have been determined. (C13H12N2O3S): Mr = 276.31, monoclinic, P21/c, a = 10.277(6), b = 7.501(2), c = 16.261(10) ?, β = 96.37(2)°, V = 1,245.8(11) ?3, Z = 4. (C14 H14 N2 O4 S): Mr = 306.33, monoclinic, P21/c, a = 10.381(5), b = 7.861(2), c = 16.837(9) ?, β = 93.43(2)°, V = 1,371.5(10) ?3, Z = 4. In both structures the phenyl rings are inclined at 47.09(7) and 39.88(5)° with respect to each other and the structures are characterized by extensive inter and intramolecular hydrogen bonds.  相似文献   

15.
The synthesis of 5-azido-3-methyl-1-phenyl-1H-pyrazolo[4,3-e][1,2,4]triazine 2 and 7-methyl-5-phenyl-1H-pyrazolo[4,3-e]tetrazolo[4,5-b][1,2,4]triazine 3 is described and the crystal and molecular structure of the latter is reported. This compound crystallizes in the monoclinic system, space group P21/n, with cell constants a = 11.607(2) Å, b = 7.982(1) Å, c = 13.147(2) Å, = 110.60(1), Z = 4, T = 293 K and Dcal = 1.470 g cm–3. The structure was solved by direct methods and refined to R value of 0.0368 for 1906 reflections. The X-ray analysis revealed that the linear form of the tetrazolo-fused ring system of 3 exists in the crystal. The molecule as a whole has an almost planar conformation stabilized by the short intramolecular NsH interaction. The molecular packing in the crystal is determined by the van der Waals forces only.Part 26 in 1,2,4-triazines in organic synthesis. For part 25 see Mojzych et al.1  相似文献   

16.

Abstract  

Two compounds isolated from the aerial parts of Verbesina turbacensis H.B.K, are reported in this work. Both compounds crystallize in the orthorhombic system, space group P212121. Compound (1), 6β-[cinnamoyloxy]-3β,4α-dihydroxyeudesmane, formula C24H34O4, has unit cell parameters a = 9.6234(2), b = 12.3137(3) and c = 18.6277(5) Å, V = 2207.38(9) Å3, Z = 4. On the other hand, 6β-[cinnamoyloxy]-eudesman-15-oic acid (2), formula C24H32O4, has cell parameters a = 8.7035(3), b = 14.2020(4), c = 17.1590(5) Å, V = 2120.97(11) Å3, Z = 4.  相似文献   

17.

Abstract  

In order to investigate the intramolecular [4 + 2] cycloaddition, we prepared some new tertiary N-(5-substituted-2-furfuryl)-N-prop-2-ynyl-p-toluidines [Hergold-Brundić et al., Acta Cryst C56:e520, 2000; Mance and Jakopčić, Mol Divers 9:229, 2005; Mance, “unpublished results”] by the alkylation of secondary N-(5-substituted-2-furfuryl)-p-toluidines with the propargyl-bromide [Mance and Šindler-Kulyk, Synth Commun 26:923, 1996]. In the course of preparation of N-(5-methoxy-2-furfuryl)-N-prop-2-ynyl-p-toluidine [Mance, “unpublished results”], besides the main product (compound 1) (Scheme 1) we obtained N,N-di(prop-2-ynyl)-p-toluidine (compound 2) as the colourless crystals. The title compound 2, N,N-di(prop-2-ynyl)-p-toluidine, C13H13N, crystallizes in monoclinic C 2/c space group with unit cell parameters: a = 19.5319(9) ?, b = 7.5230(3) ?, c = 15.9000(7) ?, β = 112.554(5)°, V = 2157.64(18) ?3, Z = 8. The crystal structure is dominated by van der Waals forces only. The bond distances around amine N atom correspond to σ dominated bonds (1.467(2), 1.462(2) and 1.419(2) ?). The angles sum around amine N atom is in accord with sp3 hybridization (343°).  相似文献   

18.
Illites from the volcanogenic Zn-Au-Ag sulfide deposit Galkinskoe (Northern Urals) have been investigated using oblique-texture electron diffraction patterns in combination with the simulation of diffraction effects. Along with single-phase tv/cv1M illites, the structures of which are formed by statistically interstratified dioctahedral 2: 1 layers with vacant trans- or cis-octahedra, illites in the form of a mixture of two interstratified tv/cv1M phases, with the dominance of tv- or cv layers, are identified. It is shown that in the latter case the diffraction pattern can also be interpreted within the single-phase tv/cv model, provided that the tv- and cv layers are distributed with some tendency to segregate. The structural features indicating the preference of the two-phase model are analyzed.  相似文献   

19.
The structure and features of the surface morphology of Pb1 − x Mn x Se (x = 0.03) epitaxial films grown on freshly cleaved BaF2(111) faces and PbSe1 − x S x (100) (x = 0.12) single-crystal wafers were investigated by molecular beam condensation and the hot-wall method. It is shown that the epitaxial films, in accordance with the data in the literature for other chalcogenides, grow in the (111) and (100) planes, repeating the substrate orientation. Black aggregates are observed on the film surface of the films grown. The results obtained are compared with the data in the literature and generalized for other chalcogenides: A 4 B 6:Pb (S, Se, Te); Pb1 − x Sn x (S, Se, Te); and Pb1 − x Mn (Se, Te). It is established that the formation of black aggregates, which are second-phase inclusions on the surface of epitaxial films obtained by vacuum thermal deposition, is characteristic of narrow-gap A 4 B 6 chalcogenides.  相似文献   

20.
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   

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