共查询到20条相似文献,搜索用时 15 毫秒
1.
Hiroyuki Hosomi Shigeru Ohba Yoshikatsu Ito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):e149-e150
In the three title crystal structures 4‐(dimethylamino)pyridinium 2,4‐dinitrobenzoate, (I), 4‐(dimethylamino)pyridinium 3,4‐dinitrobenzoate, (II), and 4‐(dimethylamino)pyridinium 3,5‐dinitrobenzoate, (III), all C7H11N2+·C7H3N2O6?, the ions are connected by an N—H?O hydrogen bond. Dihedral angles between the pyridine and phenyl rings are 69.9 (1), 26.7 (1) and 56.2 (1)° in (I), (II) and (III), respectively. Donor–acceptor π–π stacking is observed in (II) and (III), but not in (I). 相似文献
2.
Ronald D. Clark Angela Romero Oleg Ya. Borbulevych Mikhail Yu. Antipin Vladimir N. Nesterov Tatiana V. Timofeeva 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):336-338
The structures of the potential non‐linear optical (NLO) materials N‐[2‐(isopropylamino)‐5‐nitrophenyl]acetamide, (I) C11H15N3O3, and N‐[2‐(butylamino)‐5‐nitrophenyl]acetamide, (II) C12H17N3O3, have been investigated by X‐ray analysis. To compare them with the structure of N‐[2‐(dimethylamino)‐5‐nitrophenyl]acetamide, (III) C10H13N3O3, a known NLO compound, we had to redetermine the structure of (III), since it was described only briefly in the literature. There are two molecules in the asymmetric unit of compound (I), which have different orientations of the substituents with respect to the benzene ring. The packing of molecules in (II) and (III) contains stacks but both (I) and (II) crystallize in a centrosymmetric space group, which renders them inappropriate for NLO applications. 相似文献
3.
Kai Liang Yi‐Zhi Li He‐Gen Zheng Xin‐Quan Xin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m310-m312
In the title compound, [1,4‐bis(diphenylphosphino)butane‐2κ2P,P′]di‐μ‐thio‐1:2κ4S‐dithio‐1κ2S‐palladium(II)tungsten(VI) N,N′‐dimethylformamide hemisolvate hemihydrate, [PdWS4(C28H28P2)]·0.5C3H7NO·0.5H2O, the Pd atom is coordinated by two S atoms from the distorted‐tetrahedral [WS4]2− anion and two P atoms from the dppb molecule [dppb is 1,4‐bis(diphenylphosphino)butane] in an approximately square‐planar configuration. A puckered seven‐membered ring is formed by the Pd atom and the dppb ligand. 相似文献
4.
Akiko Asano Mitsunobu Doi Kenji Yoza 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o323-o325
Ceratospongamide (CS) is a potent inhibitor of secreted phospholipase A2, and cis,cis and trans,trans isomers, related with respect to the two proline amide bonds, are known. Crystals of cis,cis‐CS were grown from N,N‐dimethylacetamide solution, giving the title compound, the cyclic ester of isoleucyloxazolinylphenylalanylprolylthiazolylphenylalanylproline [cyclo(‐Ile–Oxz–Phe–Pro–Thz–Phe–Pro‐)] N,N‐dimethylacetamide hemisolvate, C41H49N7O6S·0.5C4H9NO. The structure is the third example of cis,cis‐CS to be investigated and comprises twinned crystals, in which the a and b axes are interchanged. The ratio of co‐existing twin crystals is approximately 50%. The peptide has a `saddle‐like' structure and is very similar to previously reported structures of cis,cis‐CS, which implies that the structure of cis,cis‐CS is very stable in spite of differences in crystallization conditions. 相似文献
5.
David J. Wiedenfeld Vladimir N. Nesterov Mark A. Minton David R. Glass 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o700-o702
Bis(2,5‐dimethoxy‐4‐methylphenyl)methane, C19H24O4, (IIa), was obtained and characterized as a minor product from the reaction of toluhydroquinone dimethyl ether (1,4‐dimethoxy‐2‐methylbenzene) with N‐(hydroxymethyl)trifluoroacetamide. Similarly, bis(2,5‐dimethoxy‐3,4,6‐trimethylphenyl)methane, C23H32O4, (IIb), was prepared from the corresponding reaction of trimethylhydroquinone dimethyl ether (2,5‐dimethoxy‐1,3,4‐trimethylbenzene). The molecules of (IIa) and (IIb) each lie on a twofold axis passing through the methylene group. The dihedral angle between the planar phenyl rings is 73.4 (1)° in (IIa) and 77.9 (1)° in (IIb). The external bond angles around the bridging methylene group are 116.6 (2) and 117.3 (2)° for (IIa) and (IIb), respectively. In (IIa), the methoxy substituents lie in the plane of the ring and are conjugated with the aromatic system, whereas in (IIb), they are almost perpendicular to the phenyl ring and are positioned on opposite sides. 相似文献
6.
Ayhan Elmali Ebru Kavlakoglu YalcÛn Elerman Ingrid Svoboda 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1097-1099
The title compound, aquachloro{4,4′‐dibromo‐2,2′‐[o‐phenylenebis(nitrilomethylidyne)]diphenolato‐O,N,N′,O′}iron(III)–chloro{4,4′‐dibromo‐2,2′‐[o‐phenylenebis(nitrilomethyli‐dyne)]diphenolato‐O,N,N′,O′}iron(III)–dimethylformamide (1/1/1), [FeCl(C20H12Br2N2O2)][FeCl(C20H12Br2N2O2)(H2O)]·C3H7NO, contains one independent five‐coordinate [FeCl(C20H12Br2N2O2)] monomer, one six‐coordinate [FeCl(C20H12Br2N2O2)(H2O)] monomer and a non‐coordinating dimethylformamide solvent molecule in the asymmetric unit. In the five‐coordinate monomer, the Fe atom shows distorted square‐pyramidal geometry, with the N and O atoms of the ligand at the base and the Cl atom at the apex of the pyramid. In the six‐coordinate monomer, the Fe atom is in a distorted octahedral geometry and coordinated by the donor atoms of the tetrafunctional ligand in the horizontal plane, and the coordination sphere is completed by the O atom of the water molecule and the Cl atom at the axial positions. The title compound contains intermolecular O—H?O hydrogen bonds. Apart from these hydrogen bonds, there are also intermolecular C—H?Cl and C—H?O contacts. 相似文献
7.
Akiko Asano Takeshi Yamada Atsushi Numata Mitsunobu Doi 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(9):o488-o490
The title compound, 1‐cyclohexylmethyl‐1‐de(1‐methylpropyl)ascidiacyclamide N,N‐dimethylacetamide dihydrate, C39H56N8O6S2·C4H9NO·2H2O, a cyclohexylalanine‐incorporated ascidiacyclamide analogue ([Cha]ASC), shows a square form similar to natural ASC. On the other hand, CD (circular dichroism) spectra showed [Cha]ASC to have a folded structure in solution, making it the second known analogue to show a discrepancy between its crystal and solution structures. Moreover, the cytotoxicity of [Cha]ASC (ED50 = 5.6 µg ml−1) was approximately two times stronger than that of natural ASC or a related phenylalanine‐incorporated analogue, viz. cyclo(‐Phe–Oxz–d ‐Val–Thz–Ile–Oxz–d ‐Val–Thz‐) ([Phe]ASC), and was confirmed to be associated with the square form. However, [Phe]ASC was previously shown to be folded in the crystal structure, which suggests that the difference between the aromatic and aliphatic rings affects the molecular folding of the ASC molecule. 相似文献
8.
Leah M. Schlientz Karl S. Hagen 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o533-o535
The title compound, C48H60O8·3C3H7NO, is a derivative of calix[4]arene in the cone conformation, modified with distal carboxylic acid functional groups at the lower rim. A clathrate dimethylformamide (DMF) molecule is located within the calix[4]arene cone, and two DMF solvate molecules participate in hydrogen bonding with the carboxylic acid groups. Intramolecular hydrogen bonds are also formed between the OH groups and the adjacent ether groups in the partially substituted calix[4]arene. 相似文献
9.
Catherine Corbier Claude Didierjean Laurent Thvenet Regis Vanderesse Michel Marraud 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):995-996
The pseudodipeptide, (S)‐N‐isopropyl {[N‐(pivaloyl)pyrrolidin‐2‐yl]methylaminooxy}acetamide, C15H29N3O3, adopts a global extended conformation with the hydroxylamine group in the g+/g? structure. The C‐terminal amide NH interacts intramolecularly with the hydroxylamine O atom. Both NH bonds of each molecule are hydrogen bonded to the C‐terminal amide carbonyl of a neighbouring molecule. 相似文献
10.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m1-m4
In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,2‐bis(4‐pyridyl)ethene (1/1), [Fe(C18H15O)2]·C12H10N2, there is an intramolecular O—H?O hydrogen bond in the ferrocenediol component and a single O—H?N hydrogen bond linking the diol to the diamine, which is disordered over two sets of sites, so forming a finite monomeric adduct. In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,6‐diaminohexane (2/1), 2[Fe(C18H15O)2]·C6H16N2, the amine lies across a centre of inversion in space group P. There is an intramolecular O—H?O hydrogen bond in the ferrocenediol, and the molecular components are linked by O—H?N and N—H?O hydrogen bonds, one of each type, into a C(13)[R(12)] chain of rings. 相似文献
11.
Paul V. Bernhardt Lorraine M. Caldwell David B. Lovejoy Des R. Richardson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(11):o629-o633
The X‐ray crystal structures are reported of four novel and potentially O,N,S‐tridentate donor ligands that demonstrate antitumour activity. These ligands are 1‐[(4‐methylthiosemicarbazono)methyl]‐2‐naphthol, C13H13N3OS, (III), 1‐[(4‐ethylthiosemicarbazono)methyl]‐2‐naphthol, C14H15N3OS, (IV), 1‐[(4‐phenylthiosemicarbazono)methyl]‐2‐naphthol, C18H15N3OS, (V), and 1‐[(4,4‐dimethylthiosemicarbazono)methyl]‐2‐naphthol dimethyl sulfoxide solvate, C14H15N3OS·C2H6OS, (VI). These chelators are N4‐substituted thiosemicarbazones, each based on the same parent aldehyde, namely 2‐zhydroxynaphthalene‐1‐carboxaldehyde isonicotinoylhydrazone. Conformational variations within this series are discussed in relation to the optimum conformation for metal‐ion binding. 相似文献
12.
Viktor Kettmann Jan Svetlik 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1115-1116
The title compound, C19H19N2OS+·Br?·0.5C3H7NO, is an oxygen‐bridged phenylpyrimidine derivative in which the heterocyclic ring is protonated, the positive charge being dispersed over both of the N atoms. Both molecules in the asymmetric unit exist in an identical conformation, which consists of a central planar portion with the two terminal phenyl rings protruding from the same side of the plane. One of the independent molecules forms a strong hydrogen bond with the bromide anion, while the other is hydrogen bonded to the dimethylformamide solvent molecule. 相似文献
13.
Andrzej Gzella Urszula Wrzeciono Wolfram Pppel 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):462-466
The three title compounds, namely (Z)‐1‐(4,5‐dinitroimidazol‐1‐yl)‐3‐morpholinopropan‐2‐one 2,4‐dinitrophenylhydrazone, C16H17N9O9, (IV), (Z)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐one 2,4‐dinitrophenylhydrazone, C20H25N9O8, (Va), and (E)‐3‐morpholino‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐one 2,4‐dinitrophenylhydrazone tetrahydrofuran solvate, C20H25N9O8·C4H8O, (Vb), have been prepared and their structures determined. In (IV), the C‐4 nitro group is nearly perpendicular to the imidazole ring and the C‐4—NO2 bond length is comparable to the value for a normal single Csp2—NO2 bond. In (IV), (Va) and (Vb), the C‐5 nitro group deviates insignificantly from the imidazole plane and the C‐5—NO2 bond length is far shorter in all three compounds than C‐4—NO2 in (IV). In consequence, the C‐4 nitro group in (IV) is easily replaced by morpholine, while the C‐5 nitro group in (IV), (Va) and (Vb) shows an extraordinary stability on treatment with the amine. The E configuration in (Vb) is stabilized by a three‐centre hydrogen bond. 相似文献
14.
Peter D. W. Boyd Clifton E. F. Rickard Kingsley J. Cavell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):e16-e18
The structures of a series of four‐coordinate nickel(II) complexes of the form [Ni(sacsac)L] PF6 (sacsac = pentane‐2,4‐dithione anion; L = (Ph2P)2(CH2)n, n = 1,2,3) have beendetermined. These are [bis(diphenylphosphino)methane](pentane‐2,4‐dithionato‐S,S′)nickel(II) hexafluorophosphate, [Ni(C25H22P2)(C5H7S2)]PF6, [1,2‐bis(diphenylphosphino)ethane](pentane‐2,4‐dithionato–S,S′)nickel(II) hexafluorophosphate, [Ni(C26H24P2)(C5H7S2)]PF6, and [1,3‐bis(diphenylphosphino)propane](pentane‐2,4‐dithionato‐S,S′)nickel(II) hexafluorophosphate, [Ni(C27H26P2)(C5H7S2)]PF6. All have a distorted square‐planar arrangement about Ni with angles around Ni varying with the length of the hydrocarbon chain. 相似文献
15.
Nina Lah Ivan Leban Alenka Majcen‐Le Marchal Philippe Le Grel Albert Robert Joachim Sieler Gerald Giester 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1164-1167
The crystal structures of the first stable α‐diol from the α‐halogenopyruvamide series, 3‐chloro‐2,2‐dihydroxy‐3‐phenylpropanamide, C9H10ClNO3, and three products [3‐(4‐chlorophenyl)‐2‐cyano‐2,3‐epoxypropanamide, C10H7ClN2O2, 3‐bromo‐2‐cyano‐2‐hydroxy‐3‐p‐tolylpropanamide, C11H11BrN2O2, 3‐bromo‐2‐oxo‐3‐p‐tolylpropanamide, C10H10BrNO2] obtained during the systematic synthesis of α‐halogenopyruvamides are reported. The crystal structures are dominated by hydrogen bonds involving an amide group. The stability of the geminal diol could be ascribed to hydrogen bonds which involve both hydroxyl groups. 相似文献
16.
Andrei S. Batsanov 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e269-e270
The molecule of 3,5‐difluoro‐4‐nitropyridine N‐oxide, C5H2F2N2O3, is twisted around the C—NO2 bond by 38.5 (1)°, while the 3,5‐diamino analogue, 3,5‐diamino‐4‐nitropyridine N‐oxide monohydrate, C5H6N4O3·H2O, adopts a planar conformation stabilized by intramolecular hydrogen bonds, with a significant redistribution of π electrons. 相似文献
17.
Graeme J. Gainsford Cornelis Lensink Joanne B. Hart Andrew Falshaw 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1396-1398
The title compound, 3,4,5,6‐tetramethoxycyclohexane‐1,2‐diyldioxybis(methyldiphenylphosphonium) diiodide, C36H44O6P22+·2I?, was prepared from a New Zealand natural product, d ‐chiro‐inositol, in order to develop new catalytic metal complexes. The inositol ring retains its usual chair conformation with only minor perturbations caused by the bound diphenylmethylphosphines. Crystal‐packing forces are provided by C—H?I cation–anion interactions. 相似文献
18.
Hiroyuki Hosomi Shigeru Ohba Yoshikatsu Ito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):e147-e148
In the two title compounds, N‐methylcarbazole–3,5‐dinitrobenzonitrile (1/1), C13H11N·C7H3N3O4, (I), and N‐ethylcarbazole–3,5‐dinitrobenzonitrile (1/1), C14H13N·C7H3N3O4, (II), the donor and acceptor molecules are stacked alternately to form one‐dimensional columns. In (I), the N‐methyl group of the donor is nearly eclipsed with respect to one of the nitro groups of the neighboring acceptor in a column, whereas the N‐ethyl group is anti with respect to the cyano group of the neighboring acceptor in (II). 相似文献
19.
Fangfang Jian Fengli Bei Lude Lu Xujie Yang Xin Wang Ibrahim Abdul Razak S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e288-e289
In the title compound, [Cu(C5H10NO2S2)(C18H15P)2]·C18H15P, the Cu atom is in a distorted tetrahedral coordination, with two triphenylphosphine P atoms and two S atoms from an N,N‐bis(2‐hydroxyethyl)dithiocarbamate ligand occupying the vertices. The crystal structure is characterized by alternate layers of complex and triphenylphosphine molecules. 相似文献
20.
Eleonora Freire Sergio Baggio Juan Carlos Muoz Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(8):m299-m301
The structure of the title compound, [Ni(ths)(bbip)(dmf)]·H2O [ths is thiosulfate, S2O3; bbip is 2,6‐bis(1H‐benzimidazol‐2‐yl)pyridine, C21H13N5; and dmf is dimethylformamide, C3H7NO], is monomeric, with the nickel ion octahedrally surrounded by an N,N′,N′′‐tridentate bbip molecule, an S,O‐bidentate ths molecule and an O‐monodentate dmf molecule. The H atoms of the hydration water molecule and the amino groups of bbip are involved in hydrogen bonding and determine a spatial organization of broad layers parallel to (001), which are connected by weak interactions. 相似文献