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1.
The crystal structure of 2-(1-phenylimidazolidin-2-ylidene)-malononitrile, I, and 2-(hexahydropyrimidin-2-ylidene)-malononitrile, II, were determined with crystal data (I: Monoclinic, P21/n, a=8.116(3) ?, b=7.650(3) ?, c=17.399(7) ?, β=93.065(6)°, R all=0.0980; II: Monoclinic, P21/n, a=9.169(2) ?, b=8.103(2) ?, c=10.337(3) ?, β=99.853(4)°, R all=0.0877). N−H···N hydrogen bonds were responsible for the formation of centrosymmetric dimers of I and one-dimensional zigzag molecular chains of II.  相似文献   

2.
The title compound C20H16N2S is crystallized in the monoclinic space groupP21/c with cell parametersa=10.663(4),b=17.585(9),c=9.418(5)Å,=115.23°(4),V=1598(3)Å3,Z=4. The structure was refined by full-matrix least-squares methods using X-ray data set collected at room temperature. A finalR F =0.033 andR w =0.048 for 2225 unique reflections withI> 3(I) and 272 variables was obtained. The X-ray crystallographic study establishes theZ stereochemistry of the title compound.  相似文献   

3.

Abstract  

The title compounds (bis(alkenoyl) ketene dithioacetals) were prepared starting from the cyclic acyl ketene dithioacetal and aromatic aldehydes. These compounds were characterized by IR, 1H NMR, mass spectral studies and X-ray crystal structure analysis. The bis(furyl) ketene dithioacetal crystallized in the space group P[`\text1] P{\bar{\text{1}}} with unit cell dimensions a = 7.7626(12) ?, b = 9.0217(13) ?, c = 26.827(5) ?, α = 86.271(14)°, β = 87.643(14)°, γ = 66.286(11)° and the structure was refined to an R-factor of 0.0528 while bis(thienyl) ketene dithioacetal crystallized in the space group P21/c with unit cell dimensions a = 10.2433(9) ?, b = 10.4142(6) ?, c = 18.0973(18) ?, β = 106.0° and the structure was refined to an R-factor of 0.0446. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in these compounds. In both the crystal structures, the crystal packing is stabilized by C–H···O hydrogen bonds as well as van der Waals interactions.  相似文献   

4.
Abstract  The synthesis and crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound is a curcuminoid analogue, configurationally symmetric about the C4–C5 atoms and also retains the two fold axis in the crystal phase. This compound crystallizes in the space group C2/c with unit cell parameters a = 19.203(1) ?, b = 13.147(1) ?, c = 8.801(1) ?, β = 112.99(1)°, with half a molecule in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The push-pull nature of the ketenedithioacetal functionality organizes the cinnamoyl groups parallel to each other. Index Abstract  The details regarding synthesis and crystal structure of the title compound which is a curcuminoid analogue is reported in this paper.   相似文献   

5.
The reaction between 1-phenylsulphenyl-2-phenylethyne and p-toluenesulfonic acid in methylene chloride gives (Z)-1-(phenylsulphenyl)-2-phenylethenyl p-toluenesulfonate (1) in good yields. This reaction is both a regio- and a stereospecific cis addition, confirmed by X-ray crystal structure analysis of the title compound. 1 crystallizes in the monoclinic space group P21/n with the lattice parameters a = 10.556(3), b = 9.730(3), c = 19.687(3) Å, = 105.05(2)°, V = 1952.7(8) Å3, and Z = 4. The results of elemental analysis, IR and NMR spectroscopy are included.  相似文献   

6.
Several 9-(2-R phenyl)xanthenediones have been synthesized and the x-ray diffraction structure for the 2-methylphenyl derivative (4b) has been determined. This compound crystallizes in the monoclinic system, space group P21/n, with a = 11.729 (3), b = 9.674 (3), c = 14.628 (4) Å, and = 106.30°. It presents a partially hydrogenated xanthene system in distorted boat conformation for the heterocyclic central ring, and an almost ideal envelope conformation for the outer rings. The aromatic substituent at the ninth position is at 84° in angle with the xanthene system.  相似文献   

7.
The crystal structure of the title compound is determined by X-ray diffraction studies. The structure is solved by the direct method. The experimental data are obtained on a DAR-UMB diffractometer by the θ-θ/2θ scan technique using MoK α radiation. The crystal is monoclinic, a = 17.913(3) Å, b = 17.239(3) Å, c = 5.501(5) Å, γ = 74.4(3)°, space group P21/a, Z = 4 for C17H22N4O, and ρcalcd = 1.211 g/cm3. The molecule consists of the phenyl and triazole rings and the dimethylamino, carbonyl, and isopropyl groups attached to the rings. The dihedral angle between the rings is 67.4°. The carbonyl oxygen atom and the triazole ring are in the trans position relative to each other. The N-C-C-O torsion angle is 172.8°. The molecule is in the Z isomeric form.  相似文献   

8.
The crystal structure of (Z)-5,6-dihydro-8(7H)quinolinone thiosemicarbazone has been determined by X-ray diffraction techniques in order to confirm the identity of this analog of the antineoplastic agent 2-formylpyridine thiosemicarbazone and to determine the nature of the hydrogen bonding in the solid state. The crystals are pale yellow, space groupP21/n, witha = 7.682(3),b = 10.168(8),c = 14.795(5) Å, = 103.11(4) °, andZ = 4. The structure was solved by direct methods and refined to a finalR value of 0.017. The molecule is quite planar, with the obvious exception of the central saturated carbon, and this, along with a short C-C bond at the point of attachment of the side chain, appears to be due to an interaction with the pyridyl ring. The molecules are arranged in pairs held together by mutual intermolecular SN hydrogen bonds. There is also an extensive system of intramolecular NN hydrogen bonds.  相似文献   

9.

Abstract  

The synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3-dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound crystallizes in the space group P21 with unit cell parameters a = 14.207 ?, b = 7.752(1) ?, c = 19.473(1) ?, β = 91.00(3)°, with two molecules in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The cinnamoyl groups are organized parallel to each other due to the push–pull nature of the ketenedithioacetal functionality.  相似文献   

10.

Abstract  

S-methyl 2-(5-chloro-2-oxoindolin-3-ylidene)hydrazinecarbodithioate (SM5ClISA) has been prepared from S-methyldithiocarbazate and 5-chloroisatin. The compound crystallized in monoclinic crystal system with space group P 21/n, Z = 4, V = 1201.85(7) ?3 and unit cell parameters a = 6.5466(2) ?, b = 7.5056(3) ?, c = 24.6509(8) ?, α = γ = 90° and β = 97.1434(18)°. The crystal structure reveals that the compound exists in the thione form with the chlorine occupies the fifth position in the isatin ring with the bond length of 1.739(2) ?. The 5-chloroisatin moiety is trans with respect to the C3–N2 and C3–S4 bonds whereas the methyl group of the dithiocarbazate moiety is cis with respect to the C3–N2 and C3–S5 bonds.  相似文献   

11.
Ethyl (2Z)-3-(4-chlorophenyl)-2-cyano-3-(methoxyamino)prop-2-enoate was prepared by reacting the lithium salt of ethyl cyanoacetate with (Z)-O-methyl-4-chloroben-zohydroximoyl fluoride. This compound crystallizes in space group Pbca,with lattice constants a=7.5740(15) ?, b=11.337(2) ?, and c=30.424(5) ? at 110 K. Characterizations include spectrometric identifications employing IR, UV, and 1H and 13C NMR. The compound exists in the solid as the enamine tautomer, with the cyano group cis to the 4-chlorophenyl group (the Z configuration). The C=C and C–N bond distances are 1.3930(16) ? and 1.3278(16) ?, respectively. The N–H group forms a bifurcated hydrogen bond with acceptors C=O (intramolecular) and C≡N (intermolecular).Supplementary material CCDC-289444 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by e-mailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; Fax: +44(0)1223-336033.  相似文献   

12.
The manganese complex, (Mn2(III)(salpa)2Cl2(H2O)2], has been prepared and its structure determined using x-ray crystallography. The dimer is a di-2-alkoxo complex which is a six-coordinate manganese dimer with unsupported alkoxide bridges and a rare example of a chloride- and water-containing manganese dimer. The complex crystallizes in the monoclinic space group P21/c with a = 9.315(5), b = 11.130(4), c = 11.637(5) Å, = 104.33(3)°, V = 1169.0(9) Å3, and Z = 2. The structure comprises discrete binuclear clusters in which the metal atoms are bridged by two alkoxo oxygens of the salpa2– ligands. The Mn—O and Mn—N distances are in good agreement with those found for other manganese(III) Schiff base complexes. The Mn—Cl and Mn—O3 distances are 2.585(2) and 2.371(2) Å, respectively, and the Mn ··· Mn distance is 3.001(1) Å. In the crystal, there are two types of hydrogen bonding between the H2O molecule and the Cl atom with Cl ··· H(H2O) distance of 2.33(6) (intramolecule: –1 + x, y, –1 + z) and 2.68(6) Å (intermolecule: –1 + x, 0.5–y, –0.5 + z).  相似文献   

13.
The crystal structures of two new-adrenergic antagonists, derivatives of propranolol containing 2-methylalanine fragment are described in this paper. The space groups and unit-cell parameters are: compound1 (C17H21NO4): monoclinic, space groupP21/n,a=5.787(1),b=18.703(4),c=23.526(5)Å,=96.49(2)°; compound2 (C17H22N2O3): triclinic, space groupP¯1,a=8.321(1),b=10.121(1),c=10.368(1)Å,=109.49(1)°,=90.49(1)°, =103.48(1)°. The structures were solved by direct methods and refined with full matrix least-squares techniques toR indices of 0.055 and 0.049, respectively. The molecules of compound1 exist in the crystal as dual ions. The molecules of compound2 are compact and their external chain is twisted in a characteristic way (similar to that found in peptides).  相似文献   

14.
15.
The crystal structures of two new-adrenergic antagonists, derivatives of propranolol, are reported in this paper. The space groups and unit-cell parameters are: compound1 (C18H24NO4Cl), monoclinic,P21,a=7.215(1),b=8.591(1),c=15.017(1)Å,=95.64(1)°; compound2 (C18H24N2O3), monoclinic,P21/c,a=10.218(3),b=21.616(5),c=8.124(2)Å,=101.28(2)°. The structures were solved with direct methods and refined by full-matrix least-squares techniques toR indices of 0.036 and 0.066, respectively. The molecule of compound1 has an extended external chain, and thus its structure is linear, whereas the molecule of compound2 is compact, and its external chain is twisted in a characteristic way, as is the case of peptides.  相似文献   

16.
Mr = 484, monoclinic, P 21/c, a = 5.567(1), b = 7.857(2), c = 19.194(10) Å, β = 99.97(3)°, V = 826.9 Å3, Z′ = 2, Dx = 1.43 g · cm−3, F(000) = 372, MoKα, λ = 0.71069 Å, μ = 0.328 mm−1, final R = 0.055 for 889 observed reflections, T = 293 K. The compound was prepared from a direct unusual reaction of 6-(2-thienyl)-2,3,4,5-tetrahydropyridazine-3-one with hydrazine hydrate. The structure was solved by direct methods and refined by full-matrix least squares. The molecule in the solid state consists of a dimer with its two equivalent halves related by a center of symmetry at the middle of the N N bond. Each molecular fragment is nearly planar and the N N bond between the two halves is 1.296(5) Å indicating that it is a partial double bond.  相似文献   

17.
The crystal structures of two new-adrenergic antagonists, derivatives of propranolol, are shown in this paper. The space groups and unit-cell parameters are: compound1 (C19H26NO4Cl): triclinic, space groupP1,a=6.420(1),b=10.161(1),c=15.823(1) Å,=82.47(1),=84.16(1), =77.55(1)°; compound 2 (C20H28NO4Cl): monoclinic, space groupP21/c,a=6.460(1),b=33.285(2),c=10.120(1) Å,=104.83(1)°. The structures were solved by direct methods and refined with full-matrix least-squares techniques toR indices of 0.055 and 0.048, respectively. The –CH(OH)-CH2-NH-sections of the side chains show the conformation approximate togauche.  相似文献   

18.
19.
The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by 1H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C6H7N3O is crystallized in the orthorhombic crystal system with the space group Pna21 and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.  相似文献   

20.
The molecular structure of the title compound has been determined by X-ray crystallography. The enol form is present in the solid state and each of the two molecules in the asymmetric unit possesses two intramolecular hydrogen bonds. The delocalization of double bonds results in an almost planar molecule. Evidence to support the enol configuration in solution is presented from an NMR investigation.  相似文献   

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