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1.

Abstract  

The cyclic di-amino acid peptide N,N′-diacetyl-cyclo(Gly-Gly), C8H10N2O4, crystallizes in the triclinic space group P[`1] P\bar{1} with unit cell parameters a = 9.4855(4) ?, b = 10.0250(3) ?, c = 10.0763(4) ?, α = 73.682(2)°, β = 82.816(2)°, γ = 81.733(2)°, V = 906.40(6) ?3, Z = 4 (2 molecules, A and B, per asymmetric unit), Dc = 1.452 g cm−3 and linear absorption coefficient 0.118 mm−1. The crystal structure determination was carried out with MoKα X-ray data measured at 120(2) K. In the final refinement cycle the data/restraints/parameter ratios were 4124/0/258 and goodness-of-fit on F2 = 1.0008. Final R indices for [I > 2σ(I)] were R1 = 0.0501, wR2 = 0.1007 and R indices (all data) R1 = 0.0864, wR2 = 0.11180. The largest electron density difference peak and hole were 0.241 and −0.232 e ?−3, respectively. The DKP rings in both molecules A and B have boat conformations with pseudo mm2 (C2v) symmetry if the N atoms and CH2 groups are considered identical. In each case, the prow and stern of the boat are the α-carbons C(3) and C(6). The overall molecular symmetry of molecules A and B is approximately C2 with the twofold symmetry axis of the DKP boat being maintained through the centre of the DKP ring. Details of the molecular geometry are compared with that of the parent compound cyclo(Gly-Gly) in which the DKP ring is planar with exact symmetry [`1] \bar{1} (Ci).  相似文献   

2.

Abstract  

The reactions of a new compound of N-Carboxyphenylenesulfonyl-S-Carboxymethyl-l-Cysteine (Cs-cmc) with Zn(II) or Co(II) salts in the presence of 4,4′-bipyridine (4,4′-bipy) led to the decomposition of Cs-cmc and produced [Zn(4,4′-bipy)(H2O)4]X2 (X = p-sulfamoylbenzoate) 1 and [Co(4,4′-bipy)(H2O)4]Y·H2O (Y = p-sulfonatobenzoate) 2, in which the decomposition products of Cs-cmc exist as free counter-anions. The single crystal X-ray diffraction analyses revealed that compound 1 crystallizes in monoclinic C2/c space group with a = 18.748(4) ?, b = 11.520(2) ?, c = 12.751(3) ?, β = 90.290(4)°, V = 2753.9(10) ?, Z = 4 and compound 2 crystallizes in orthorhombic Pca21 space group with a = 12.114(3) ?, b = 11.369(2) ?, c = 14.770(3) ?, V = 2034.1(7) ?, Z = 4. It was revealed that 1D chains were constructed from metal ions and 4,4′-bipy in both compounds. The 1D chains interact with the counter-anions by hydrogen bonds, forming 3D supramolecular structures.  相似文献   

3.

Abstract  

N-acetyl-l-glutamic acid, crystallizes in the orthorhombic space group P212121 with unit cell parameters a = 4.747(3), b = 12.852(7), c = 13.906(7) Å, V = 848.5(8) Å3, Z = 4, density (calculated) = 1.481 mg/m3, linear absorption coefficient 0.127 mm−1. The crystal structure determination was carried out with MoKα X-ray data measured with liquid nitrogen cooling at 100(2) K temperature. In the final refinement cycle the data/restraints/parameter ratios were 1,691/0/131; goodness-of-fit on F 2 = 1.122. Final R indices for [I > 2sigma(I)] were R1 = 0.0430, wR2 = 0.0878 and R indices (all data) R1 = 0.0473, wR2 = 0.0894. The largest electron density difference peak and hole were 0.207 and −0.154 eÅ−3. Details of the molecular geometry are discussed and compared with a model DFT structure calculated using Gaussian 98.  相似文献   

4.

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   

5.
Abstract  The dl-lomenfloxacin hydrate is an innersalt, which crystallizes in space group C2/c with cell parameters a = 22.897(10), b = 8.682(1), c = 18.365(2) ?, β = 93.633(9)°, V = 3,705(3) ?3 and Z = 8. The piperazinyl ring adopts a chair conformation, and the quinolone ring is essentially planar. The plane defined by C atoms of the piperazinyl ring is not coplanar with the quinolone ring. The carboxylate group shows two disorder parts, and is not coplanar with the quinolone ring, the dihedral angle between them is 113.8°. The disorder carboxylate group is split into two parts, the planes of which are skewed at the dihedral angles of 24.5 and 21.6° with the plane of the quinolone ring, respectively. The IR of the title compound is measured and studied. Index abstract  The crystal structure of dl-lomenfloxacin hydrate is determined by X-ray diffraction. The IR is measured and shows great differences from previous studies.   相似文献   

6.
Abstract   One trinuclear di-n-butyltin(IV) complex with salicylaldoxime (o-HON=CHC6H4OH=HONZOH), (Bu2Sn)(Bu2SnO)(Bu2SnOH)(ONZOH)(ONZO), has been synthesized and characterized by elemental analyses, IR spectrum, and single crystal X-ray diffraction. This complex is a small cluster displaying two unequivalent salicylaldoximate with one seven-coordinate pentagonal–bipyramidal tin atom linked two five-coordinate trigonal–bipyramidal tin atoms via a network of oxygen atoms by Sn–O–Sn bridges. The hydrogen bonds (o-HON=CHC6H4–O…H–O) are observed in the complex. These hydrogen bonds include intramolecular hydrogen bonds and intermolecular hydrogen bonds. (Bu2Sn)(Bu2SnO)(Bu2SnOH)(ONZOH)(ONZO) belongs to monoclinic: space group P21/n, with a = 12.2307(15) ?, b = 17.361(2) ?, c = 20.976(3) ?, β = 94.424(2)°, V = 4440.5(10) ?3, Z = 4, D c  = 1.500 g/cm3, μ(MoKα) = 1.715 mm−1, F(000) = 2024, and final R 1 = 0.0426, wR 2 = 0.1064 for observed reflections 7779(I > 2σ(I)). Index abstract  The title compound, di-n-butyltin(IV) complex with salicylaldoxime, was synthesized and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that the molecular structure of the title compound is trinuclear. The complex is a small cluster displaying two unequivalent salicylaldoximate with one seven-coordinate pentagonal–bipyramidal tin atom linked two five-coordinate trigonal–bipyramidal tin atoms via a network of oxygen atoms by Sn–O–Sn bridges.   相似文献   

7.

Abstract  

Crystalline hydrate of the title compound (5), C19H26N2O5·2(H2O), was structurally characterized by single crystal X-ray diffraction. It crystallizes in monoclinic system space group P 21/c with a = 7.3987(7) ?, b = 17.8691(16) ?, c = 17.0022(13) ?, β = 112.944(3)°, V = 2070.0(3) ?3, Z = 4, R 1 = 0.0592, wR 2 = 0.1016, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with 3,4-dimethoxybenzene ring, making a dihedral angle of 0.860(69)°. Two kinds of centrosymmetric tetramers characterized by graph-set motifs of R 78(36) and R 46(32) are formed through O–H···O, O–H···N and C–H···O hydrogen bonding interactions, which generate a sheet of edge-fused rings parallel to the (011) plane. These sheets are further linked into a three dimensional network by C–H···π interactions. Nine 3-(3,4-dimethoxyphenyl)furan-2(5H)-ones were synthesized and fully characterized by elemental analysis, MS and 1H NMR. All of them were evaluated for antimicrobial activities against three Gram-positive organisms and a Gram-negative organism, and compound 5 was the most active against Staphylococcus aureus ATCC 25923.  相似文献   

8.

Abstract  

A 1:1 co-crystal structure of 11-hydroxy-2,3,9-trimethoxy-6H-chromeno[3,4-b]chromen-12-one and 11-hydroxy-2,3,9-trimethoxy-chromeno[3,4-b]chromene-6,12-dione (stemonone) was crystallized from the reaction mixture of 6-deoxyclitoriacetal and methanesulfonyl chloride, and its structure was characterized by X-ray diffraction. This co-crystal crystallizes in a triclinic crystal system, space group P(−1) with unit cell parameters of a = 8.1317(3) Å, b = 9.8224(4) Å, c = 10.7268(3) Å, α = 78.116(1)°, β = 77.463(1)°, γ = 77.140(1)°, Z = 2 and V = 804.11(3) Å3. The crystal structure was solved by direct methods and refined by full-matrix least-squares on F 2 to final values of R 1 = 0.0501 and wR 2 = 0.1520.  相似文献   

9.

Abstract  

The crystal structure of methyl 1,4-di[(E)-2-(p-tolyl)-1-diazenyl]piperazine (4) has been determined by single crystal X-ray diffraction analysis. The bis-triazene (4) adopts a normal chair conformation in the piperazine ring, with puckering parameters : φ2 = −29(5)°, QT = 0.534(2) ? and θ2 = 177.0(2)°. The crystal structure of 4 is compared with the structure of the triazene (2a) and the closely related bis-triazenes (3 and 5a). The piperazine ring of 2a and 4 adopt a typical chair conformation, whereas the piperazine ring of 3 adopts an unusual pseudo-boat conformation. Crystal data: 4 C18H22N6, triclinic, space group P[`1] P\overline{1} , a = 6.8925(2) ?, b = 7.8574(3) ?, c = 16.8856(8) ?, α = 103.103(2)°, β = 90.528(2)°, γ = 101.776(2)° and V = 870.44 (6) ?3, for Z = 2.  相似文献   

10.

Abstract  

The mixed ligand dithiocarbamate complex was synthesized by the reaction between the ammonium salt of the dithiocarbamate ligands with mercury salt. There are two mercury complexes in the asymmetric unit with a compositional disorder between an ethyl group and a methyl group. A distorted tetrahedral geometry is found for each mercury atom defined by four sulphur atoms derived from two asymmetrically chelating dithiocarbamate ligands. IR spectra show thioureide υ(C–N) bands at 1491 cm−1 which is higher than observed in the simple complexes of the same ligands. The effect of alkyl substituents were observed in the magnetic unequivalence of the thioureide and phenyl units in the NMR spectroscopy. The molecules are related to each other by virtue of the compositional disorder which exists at three positions in the alkyl group across the unit. The compound crystallizes in the triclinic space group P-1 with a = 10.4764(10) ?, b = 11.0433(10) ?, c = 18.5566(17) ?, α = 97.8980(10)°, β = 95.3340(10)°, γ = 110.3010(10)°, and Z = 2.  相似文献   

11.

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   

12.

Abstract  

The title compound 2-(4,5-bis(4-methoxyphenyl)-5H-chromeno[4,3-b]pyridin-2-yl)- phenol (C32H25NO4, Mr = 487.53) was synthesized and crystallized. The crystal belongs to monoclinic, space group P2(1)/c with a = 12.4170 (11), b = 18.313 (2), c = 11.7103 (10) ?, β = 111.569(2)°, V = 2476.4(4) ?3, Mr = 487.53, Z = 4, Dc = 1.308 g/cm3, μ(MoK α ) = 0.086 mm−1, F(000) = 1024, the final R 1 = 0.0632 and wR 2 = 0.1454. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a planar six-membered ring, while the atoms of C(1), C(2), C(6), C(7), C(12) and O(1) form a six-membered ring of envelope conformation.  相似文献   

13.

Abstract  

Schiff base 4-[(2-hydroxy-3-methoxybenzylideneamino)-N-(5-methylisoxazol-3-yl)benzene-sulfonamide has been synthesized from the reaction of 4-amino-N-(5-methylisoxazol-3-yl)benzenesulfonamide(sulfamethoxazole) with 2-hydroxy-3-methoxybenzaldehyde. It has been characterized by elemental analysis, MS, IR, 1H NMR, 13C NMR, HETCOR and UV–Visible techniques. The structure of it also has been examined crystallographically. For the compound exist as dominant form of enol-imines in both the solid state and the solutions. It crystallizes in the monoclinic space group P21/c with a = 8.2694(7), b = 8.3453(5), c = 26.260(2) ?, β = 97.142(7) °, V = 1798.1(2) ?3, D x  = 1.431 g cm−3, R 1 = 0.0529 and wR 2 = 0.1370 [I > 2σ(I)], respectively.  相似文献   

14.

Abstract  

A new type of substituted benzothiopyranone, 3-phenyl-2-(2-phenylhydrazino)-4H-1-benzothiopyran-4-one, has been prepared by the condensation-acid cyclization of polylithiated phenylacetic acid phenylhydrazide with lithiated methyl thiosalicylate. Absorption spectra, especially 13C NMR, provided good indication of its structure, which was conclusively established with X-ray crystal structure analysis. In comparison to the few benzothiopyran X-ray reports documented, the benzothiopyranone ring of the molecule was found to be essentially planar, with the 3-phenyl ring nearly perpendicular to the benzothiopyranone fused-ring system. Crystals of C21H16N2OS are orthorhombic, P212121, a = 10.140(4) ?, b = 10.432(4) ?, c = 16.228(7) ?, Z = 4, V = 1717(1) ?3, R 1 = 0.0267 and wR 2 = 0.0725 for reflections with I > 2σ(I). The molecular packing in the crystal is the result of N–H···O hydrogen bonding.  相似文献   

15.

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   

16.

Abstract  

(5-Methyl-3-phenyl-1H-pyrazol-1-yl)-[5-(p-tolylamino)-2H-1,2,3-triazol-4-yl]methanone was synthesized and characterized by 1H NMR, MS and IR spectra data. The structure of title compound was identified by X-ray diffraction. Compound, C20H18N6O, Mr = 358.40, crystallizes in the triclinic space group P-1 with unit cell parameters a = 10.303(6), b = 12.489(7), c = 15.305(9) ?, α = 108.489(12), β = 101.920(11), γ = 96.971(13)°, V = 1790.0(17) ?3, Z = 4, Dx = 1.330 mg/cm3. The final R was 0.0520.  相似文献   

17.

Abstract  

The molecular and crystal structure of the title compound, C14H11Cl2NO, has been determined by X-ray single crystal diffraction technique. The compound crystallizes in the orthorhombic, space group Pbca with unit cell dimensions a = 7.5537(10) ?, b = 11.5518(13) ?, c = 29.760(4) ?, M r  = 280.14, V = 2596.8(6) ?3, Z = 8, R 1 = 0.065 and wR 2 = 0.191. The title compound exists in the enol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond. The dihedral angle between the two benzene rings is 37.66(15)°. The asymmetric unit in the crystal structure contains only one neutral molecule. Calculational studies were performed by using AM1, PM3, PM6 semi-empirical and DFT methods. Geometry optimizations of compound have been carried out by using three semi-empirical methods and DFT method and bond lengths, bond and torsion angles of title compound have been determined. Dipole moments (Debye) and the energy parameters of compound (kcal/mol) were calculated by using above mentioned calculation methods. Atomic charge distribution has been obtained from AM1, PM3, PM6 and DFT. In order to determine conformational flexibility on the molecule, molecular energy profile of the title compound was obtained with respect to the selected torsion angle T(N1–C7–C1–C2), which is varied from −180° to +180° in every 10 via PM3 semi-empirical method.  相似文献   

18.

Abstract  

Two novel ferrocenyl substituted N-acetyl-2-pyrazolines, N-acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline (3) and N-acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline (4), have been synthesized and characterized by FTIR, 1H-NMR, 13C-NMR techniques, elemental analysis and X-ray structure analysis. Thermal properties of these compounds have been determined by TGA, DTA and DSC analysis. Compound 3 (C19H18N2O2Fe) crystallizes in the monoclinic space group P21/c and Z = 4, with a = 8.6970(4) ?, b = 18.4725(9) ?, c = 11.0041(5) ?, β = 110.942(3)°. Compound 4 (C19H18N2OSFe) crystallizes in the orthorhombic space group Fdd2 and Z = 16, with a = 84.242(2) ?, b = 13.5416(5) ?, c = 5.9405(2) ?, β = 90°. In terms of crystal packing, each compound shows different molecular arrangement, which are stabilized by C–H···O intermolecular weak hydrogen bonds, and/or C–H···π interactions.  相似文献   

19.
Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C18H21NO3, M r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?3, Z = 4, D c = 1.218 g cm−3, λ = 0.71073 ?, μ(Mo ) = 0.083 mm−1, F(000) = 640. The final refinement gave R = 0.0497, wR(F 2) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and ππ stacking interactions. The title compound possesses moderate antibacterial activity. Graphical Abstract  The title compound N-(2,3,4-trimethoxy-6-methylbenzylidene)-2-methyl-benzenamine (C18H21NO3, M r = 299.36) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 7.2804(5), b = 8.5909(9), c = 26.117(3) ?, β = 92.056(2)°, V = 1,632.4(3) ?3, Z = 4, D c = 1.218 g cm−3, λ = 0.71073 ?, μ(Mo ) = 0.083 mm−1, F(000) = 640. The final refinement gave R = 0.0497, wR(F 2) = 0.1157 for 2,879 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the dihedral angle between the two phenyl rings is 25.9 (2)°. The molecule adopts a trans configuration about the central C=N functional bond. The crystal structure is stabilized by C–H…O hydrogen bonds and ππ stacking interactions. The title compound possesses moderate antibacterial activity.   相似文献   

20.

Abstract  

The diastereoselective synthesis, NMR and X-ray structure of (S)-2-((S)-2-(N-Ts-amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one—a potential antivirus agent are reported. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 5.9259(6) ?, b = 9.6370(12) ?, c = 12.9541(9) ?, α = 109.210(9)°, β = 90.804(7)°, γ = 105.074(10)° and Z = 1.  相似文献   

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