共查询到20条相似文献,搜索用时 15 毫秒
1.
Alexander J. Blake Peter Hubberstey Alexander D. Mackrell Claire Wilson 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o293-o297
The trans–trans conformations adopted by the derivatized bis(bidentate) chelating N4‐donor ligand 3,6‐bis(pyrazol‐1‐yl)‐4‐[2‐(4‐thiamorpholino)ethanesulfanyl]pyridazine, C16H19N7S2, and an intermediate in its formation, 3,6‐dichloro‐4‐[2‐(4‐thiamorpholino)ethanesulfanyl]pyridazine, C10H13Cl2N3S2, contrast with the cis–cis conformation found previously for 3,6‐bis(thiophen‐2‐yl)pyridazine [Ackers, Blake, Hill & Hubberstey (2002). Acta Cryst. C 58 , o640–o641], which places all four heteroatoms on the same side of the molecule. 相似文献
2.
Sankar Prasad Dey Dilip Kumar Dey Asok Kumar Mallik Lutz Dahlenburg 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o321-o322
The title compound, 2‐hydroxyphenyl 5‐(pyrrol‐2‐yl)‐3H‐pyrrolizin‐6‐yl ketone, C18H14N2O2, was isolated from the base‐catalyzed 1:2 condensation of 2‐hydroxyacetophenone with pyrrole‐2‐carbaldehyde. The pyrrole N—H and hydroxybenzoyl O—H groups are hydrogen bonded to the benzoyl O atom. The allylic C=C double bond of the 3H‐pyrrolizine system is located between ring positions 1 and 2, the C atom at position 3 (adjacent to the N atom) being single bonded. 相似文献
3.
Robert T. Stibrany Harvey J. Schugar Joseph A. Potenza 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o354-o357
Two of the title compounds, namely (E)‐1,2‐bis(1‐methylbenzimidazol‐2‐yl)ethene, C18H16N4, (Ib), and (E)‐1,2‐bis(1‐ethylbenzimidazol‐2‐yl)ethene, C20H20N4, (Ic), consist of centrosymmetric trans‐bis(1‐alkylbenzimidazol‐2‐yl)ethene molecules, while 3‐ethyl‐2‐[(E)‐2‐(1‐ethylbenzimidazol‐2‐yl)ethenyl]benzimidazol‐1‐ium perchlorate, C20H21N4+·ClO4−, (II), contains the monoprotonated analogue of compound (Ic). In the three structures, the benzimidazole and benzimidazolium moieties are essentially planar; the geometric parameters for the ethene linkages and their bonds to the aromatic groups are consistent with double and single bonds, respectively, implying little, if any, conjugation of the central C=C bonds with the nitrogen‐containing rings. The C—N bond lengths in the N=C—N part of the benzimidazole groups differ and are consistent with localized imine C=N and amine C—N linkages in (Ib) and (Ic); in contrast, the corresponding distances in the benzimidazolium cation are equal in (II), consistent with electron delocalization resulting from protonation of the amine N atom. Crystals of (Ib) and (Ic) contain columns of parallel molecules, which are linked by edge‐over‐edge C—H⋯π overlap. The columns are linked to one another by C—H⋯π interactions and, in the case of (Ib), C—H⋯N hydrogen bonds. Crystals of (II) contain layers of monocations linked by π–π interactions and separated by both perchlorate anions and the protruding ethyl groups; the cations and anions are linked by N—H⋯O hydrogen bonds. 相似文献
4.
Hong‐Yan Wu Yun‐Feng Feng Shu‐Rong Wang Wei‐Ping Huang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):m358-m359
In the title copper(II) compound, [Cu(C7H4BrO2)(ClO4)(C12H8N2)], the Cu atom is five‐coordinated in a distorted square‐pyramidal geometry by the N‐ and O‐donors of 4‐bromo‐2‐formylphenolate, 1,10‐phenanthroline and perchlorate. Pairs of complexes are linked together by Cu⋯O(phenolate) and π–π stacking interactions between 4‐bromo‐2‐formylphenolate and 1,10‐phenanthroline. Along the crystallographic a axis, the dimers are linked by hydrogen bonds between a perchlorate O atom and a 4‐bromo‐2‐formylphenolate H atom, and by further π–π stacking interactions. Hydrogen bonding between the Br atom and a 1,10‐phenanthroline H atom takes place between the stacks of dimers. 相似文献
5.
Serguei Prikhodovski Martin Brring Silke Khler 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):m68-m70
In the crystal structure, the title compound {systematic name: [2,5‐bis(4‐ethyl‐3,5‐dimethyl‐2H‐pyrrol‐2‐ylidenemethyl)‐1H‐pyrrolato](trifluoroacetato)palladium(II)}, [Pd(C2F3O2)(C27H34N3)], forms chiral molecules with a helical distortion of the tripyrrinate ligand backbone and an essentially planar PdN3O core, with Pd—N distances ranging from 1.977 (3) to 2.045 (3) Å and a Pd—O distance of 2.051 (2) Å. This distortion of the organic ligand is considered as the conformational answer to the steric interaction of the terminal methyl groups of the tripyrrinate ligand with the donor O atom of the trifluoroacetate group. 相似文献
6.
Yavuz Kysal amil Ik Gülay ahin Erhan Palaska 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o542-o544
The structures of N‐ethyl‐3‐(4‐fluorophenyl)‐5‐(4‐methoxyphenyl)‐2‐pyrazoline‐1‐thiocarboxamide, C19H20FN3OS, (I), and 3‐(4‐fluorophenyl)‐N‐methyl‐5‐(4‐methylphenyl)‐2‐pyrazoline‐1‐thiocarboxamide, C18H18FN3S, (II), have similar geometric parameters. The methoxy/methyl‐substituted phenyl groups are almost perpendicular to the pyrazoline (pyraz) ring [interplanar angles of 89.29 (8) and 80.39 (10)° for (I) and (II), respectively], which is coplanar with the fluorophenyl ring [interplanar angles of 5.72 (9) and 10.48 (10)°]. The pyrazoline ring approximates an envelope conformation in both structures, with the two‐coordinate N atom involved in an intramolecular N—H⋯Npyraz interaction. In (I), N—H⋯O and C—H⋯S intermolecular hydrogen bonds are the primary interactions, whereas in (II), there are no intermolecular hydrogen bonds. 相似文献
7.
Tullio Pilati Gianluigi Casalone 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o178-o180
The title diastereoisomers, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate and methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, both C19H23N3O5, have been studied in two crystalline forms. The first form, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate–methyl 5‐(S)‐[2‐(R)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate (1/1), 2(S),5(S)‐C19H23N3O5·2(R),5(S)‐C19H23N3O5, contains both S,S and S,R isomers, while the second, methyl 5‐(S)‐[2‐(S)‐methoxycarbonyl)‐2,3,4,5‐tetrahydropyrrol‐1‐ylcarbonyl]‐1‐(4‐methylphenyl)‐4,5‐dihydropyrazole‐3‐carboxylate, 2(S),5(S)‐C19H23N3O5, is the pure S,S isomer. The S,S isomers in the two structures show very similar geometries, the maximum difference being about 15° on one torsion angle. The differences between the S,S and S,R isomers, apart from those due to the inversion of one chiral centre, are more remarkable, and are partially due to a possible rotational disorder of the 2‐(methoxycarbonyl)tetrahydropyrrole group. 相似文献
8.
Intermolecular stacking in pyrazolo[3,4‐d]pyrimidine‐based pentamethylene‐linked flexible molecules
Kamlakar Avasthi Sheikh M. Farooq Ashish K. Tewari Ashoke Sharon Prakas R. Maulik 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):o42-o45
The crystal structures of 1‐{5‐[4,6‐bis(methylsulfanyl)‐2H‐pyrazolo[3,4‐d]pyrimidin‐2‐yl]pentyl}‐6‐methylsulfanyl‐4‐(pyrrolidin‐1‐yl)‐1H‐pyrazolo[3,4‐d]pyrimidine, C22H29N9S3, and 6‐methylsulfanyl‐1‐{5‐[6‐methylsulfanyl‐4‐(pyrrolidin‐1‐yl)‐2H‐pyrazolo[3,4‐d]pyrimidin‐2‐yl]pentyl}‐4‐(pyrrolidin‐1‐yl)‐1H‐pyrazolo[3,4‐d]pyrimidine, C25H34N10S2, which differ in having either a pyrrolidine substituent or a methylsulfanyl group, show intermolecular stacking due to aromatic π–π interactions between the pyrazolo[3,4‐d]pyrimidine rings. 相似文献
9.
Arthur Camerman Andrew Hempel Donald Mastropaolo Norman Camerman 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(7):o417-o419
In the crystal structure of 2‐acetamido‐N‐benzyl‐2‐(methoxyamino)acetamide (3L), C12H17N3O3, the 2‐acetylaminoacetamide moiety has a linearly extended conformation, with an interplanar angle between the two amide groups of 157.3 (1)°. In 2‐acetamido‐N‐benzyl‐2‐[methoxy(methyl)amino]acetamide (3N), C13H19N3O3, the planes of the two amide groups intersect at an angle of 126.4 (4)°, resulting in a chain that is slightly more bent. The replacement of the methoxyamino H atom of 3L with a methyl group to form 3N and concomitant loss of hydrogen bonding results in some positional/thermal disorder in the methoxy(methyl)amino group. In both structures, in addition to classical N—H⋯O hydrogen bonds, there are also weak non‐standard C—H⋯O hydrogen bonds. The hydrogen bonds and packing interactions result in planar hydrophilic and hydrophobic areas perpendicular to the c axis in 3L and parallel to the ab plane in the N‐methyl derivative. Stereochemical comparisons with phenytoin have identified two O atoms and a phenyl group as molecular features likely to be responsible for the anticonvulsant activities of these compounds. 相似文献
10.
Dens Konya Christian Philouze Yves Gimbert Andrew E. Greene 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o108-o111
Three chiral electron‐deficient phosphine ligands, [(4R,15R)‐,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]diethylamine, C12H20F6N3O4PS2, (IIIa), [(4R,5R)‐1,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]dimethylamine, C10H16F6N3O4PS2, (IIIb), and bis[(4R,5R)‐1,3‐bis(trifluoromethanesulfonyl)perhydro‐1,3,2‐benzodiazaphosphol‐2‐yl]methylamine, (IV), as the chloroform solvate, C17H23F12N5O8P2S4·0.98CHCl3, have been prepared from (1R,2R)‐N,N′‐bis(trifluoromethanesulfonyl)‐1,2‐cyclohexanediamine and diethyl phosphoramidous dichloride, dimethyl phosphoramidous dichloride or methyl imidodiphosphorus tetrachloride. The π‐acceptor abilities of these new types of ligands have been evaluated by X‐ray determination of the P—N bond lengths; it has been found that the most promising ligand is the bis(phosphine) (IV). 相似文献
11.
Ivan Halasz Kaja Luki Hrvoj Van
ik 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(1):o61-o64
4‐Amino‐trans‐azobenzene {or 4‐[(E)‐phenyldiazenyl]aniline} can form isomeric salts depending on the site of protonation. Both orange bis{4‐[(E)‐phenyldiazenyl]anilinium} hydrogen phosphate, 2C12H12N3+·HPO42−, and purple 4‐[(E)‐phenyldiazenyl]anilinium dihydrogen phosphate phosphoric acid solvate, C12H12N3+·H2PO4−·H3PO4, (II), have layered structures formed through O—H⋯O and N—H⋯O hydrogen bonds. Additionally, azobenzene fragments in (I) are assembled through C—H⋯π interactions and in (II) through π–π interactions. Arguments for the colour difference are tentatively proposed. 相似文献
12.
Makoto Eishima Shigeru Ohba Masumi Suzuki Chiaki Nagasawa Takeshi Sugai 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1391-1393
In the racemic crystals of (1S,2R)‐ or (1R,2S)‐1‐[N‐(chloroacetyl)carbamoylamino]‐2,3‐dihydro‐1H‐inden‐2‐yl chloroacetate, C14H14Cl2N2O4, (I), the enantiomeric molecules form a dimeric structure via the N—H?O cyclic hydrogen bond of the carbamoyl moieties. In the chiral crystals of (—)‐(1S,2R)‐1‐[N‐(chloroacetyl)carbamoylamino]‐2,3‐dihydro‐1H‐inden‐2‐yl chloroacetate, C14H14Cl2N2O4, (II), the N—H?O intermolecular hydrogen bond forms a zigzag chain around the twofold screw axis. The melting points and calculated densities of (I) and (II) are 446 and 396 K, and 1.481 and 1.445 Mg m?3, respectively. 相似文献
13.
Xiaomei Zhang Simone Budow Peter Leonard Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(2):o79-o81
In the title compound, 4‐amino‐2‐(2‐O‐methyl‐β‐d ‐ribofuranosyl)‐2H‐pyrazolo[3,4‐d]pyrimidine monohydrate, C11H15N5O4·H2O, the conformation of the N‐glycosylic bond is syn [χ = 20.1 (2)°]. The ribofuranose moiety shows a C3′‐endo (3T2) sugar puckering (N‐type sugar), and the conformation at the exocyclic C4′—C5′ bond is −ap (trans). The nucleobases are stacked head‐to‐head. The three‐dimensional packing of the crystal structure is stabilized by hydrogen bonds between the 2′‐O‐methylribonucleosides and the solvent molecules. 相似文献
14.
Burkhard Schulz Julia Bricks Yan‐Qin Li Ute Resch‐Genger Günter Reck 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o402-o404
1‐Methyl‐2‐[4‐phenyl‐6‐(pyridinium‐2‐yl)pyridin‐2‐yl]pyridinium diperchlorate, C22H19N32+·2ClO4−, (I), and 2‐[4‐(methoxyphenyl)‐2,2′‐bipyridin‐6‐yl]‐1‐methylpyridinium iodide, C23H20N3O+·I−, (II), both crystallize in the monoclinic space group P21/c. In contrast with the monocharged molecule of (II), the doubly charged molecule of (I) contains an additional protonated pyridine ring. One of the two perchlorate counter‐anions of (I) interacts with the cation of (I) via an N—H⋯O hydrogen bond. In (II), two molecules related by a centre of symmetry are connected by weak π–π interactions, forming dimers in the crystal structure. 相似文献
15.
Xiaohua Peng Frank Seela Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):o96-o98
In the title compound [systematic name: 7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐2‐fluoro‐7H‐pyrrolo[2,3‐d]pyrimidin‐2‐amine], C11H13FN4O3, the conformation of the N‐glycosylic bond is between anti and high‐anti [χ = −110.2 (3)°]. The 2′‐deoxyribofuranosyl unit adopts the N‐type sugar pucker (4T3), with P = 40.3° and τm = 39.2°. The orientation of the exocyclic C4′—C5′ bond is −ap (trans), with a torsion angle γ = −168.39 (18)°. The nucleobases are arranged head‐to‐head. The crystal structure is stabilized by four intermolecular hydrogen bonds of types N—H⋯N, N—H⋯O and O—H⋯O. 相似文献
16.
Jie‐Ying Wu Suchada Chantrapromma Dong‐Wen Chen Yu‐Peng Tian Ping Yang Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):523-525
The tetradentate N2S2 Schiff base ligand 3,3′‐[2,2′‐(ethylenedioxy)dibenzylidene]bis(S‐methyl dithiocarbazate) (H2L), prepared by the condensation of S‐methyl dithiocarbazate with 1,4‐bis(2‐formylphenyl)‐1,4‐dioxabutane in a 1:2 molar ratio, reacts with nickel acetate to form the title neutral metal complex, [Ni(C20H20N4O2S4)]. The X‐ray structure of the complex shows a distorted square‐planar geometry around the Ni atom. The monomeric units are weakly associated into dimers via a long Ni?S interaction [3.569 (1) Å]. These dimeric units are then linked by C—H?S intermolecular contacts to form a polymeric chain along the a axis. 相似文献
17.
Marisa Spiniello Jonathan M. White 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o94-o96
The structures of cis‐ and trans‐2‐(4‐tert‐butylcyclohexyloxy)‐1,3,5‐trinitrobenzene, C16H21N3O7, (I) and (II), respectively, were determined at low temperature in order to obtain accurate structural parameters for comparison purposes. The Calkyl—Oether bond distances are 1.497 (2) and 1.491 (2) Å for (I) and (II), respectively. 相似文献
18.
Bi‐Yun Su Jia‐Xiang Wang Xiang Liu Qian‐Ding Li 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):522-525
The title isomers, namely 3‐chloro‐N‐[1‐(1H‐pyrrol‐2‐yl)ethylidene]aniline, (I), and 4‐chloro‐N‐[1‐(1H‐pyrrol‐2‐yl)ethylidene]aniline, (II), both C12H11ClN2, differ in the position of the chlorine substitution. Both compounds have the basic iminopyrrole structure, which shows a planar backbone with similar features. The dihedral angle formed by the planes of the pyrrole and benzene rings is 75.65 (7)° for (I) and 86.56 (8)° for (II). The H atom bound to the pyrrole N atom is positionally disordered and partial protonation occurs at the imino N atom in (I), while this phenomenon is absent from the structure of (II). Packing interactions for both compounds include intermolecular N—H...N hydrogen bonds and C—H...π interactions, forming centrosymmetric dimers for both (I) and (II). 相似文献
19.
Boris B. Averkiev Mikhail Yu. Antipin Aleksey B. Sheremetev Tatiana V. Timofeeva 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o383-o387
In earlier papers, we described the synthesis and structures of bis(3‐nitrofurazan‐4‐yl) ether, C4N6O7, (I), bis[3‐(nitro‐N,N,O‐azoxy)furazan‐4‐yl] ether, C4N10O9, (II), and bis[3‐(5H‐[1,2,3]triazolo[4,5‐c]furazan‐5‐yl)furazan‐4‐yl] ether, C8N14O5, (III). Here we compare the structures of (I)–(III) with those of four 3‐cyanodifurazanyl ethers, namely bis(3‐cyanofurazan‐4‐yl) ether, C6N6O3, (IV), 3‐cyanofurazanyl 3‐nitrofurazanyl ether, C5N6O5, (V), 3,4‐bis(3‐cyanofurazan‐4‐yloxy)furazan, C8N8O5, (VI), and bis[3‐(3‐cyanofurazan‐4‐yloxy)furazan‐4‐yl]diazene, C10N12O6, (VII). It was found that the geometric parameters of the difurazanyl ether fragments are similar in these structures and therefore not influenced by substituent effects; however, the conformation of this fragment is different, viz. structures (I), (III), (V) and (VI) have approximate C2 symmetry, and structures (II), (IV) and (VII) have Cs symmetry. Dense crystal packing (1.626–1.898 Mg m−3) is characteristic for all these hydrogen‐free compounds. A linear correlation is also determined between crystal density and `molecular density' (M/V), where M is the mass of a molecule and V is the molecular volume. 相似文献
20.
Ahmet Karadag Hümeyra Paaoglu Gkhan Kata Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):m581-m583
The title compound, catena‐poly[[μ‐cyano‐1:2κ2C:N‐dicyano‐1κ2C‐trans‐bis[N‐(2‐hydroxyethyl)ethane‐1,2‐diamine‐2κ2N,N′]cadmium(II)nickel(II)]‐μ‐cyano‐1:2′κ2C:N], [CdNi(CN)4(C4H12N2O)2], consists of alternating square‐planar Ni(CN)4 fragments, formally dianionic, and Cd(hydet‐en)2 moieties [hydet‐en is N‐(2‐hydroxyethyl)ethylenediamine], with the two bridging cyanide ligands in a mutually trans disposition at the Ni atom and cis at the Cd atom. The resulting one‐dimensional zigzag chain structure has the Ni atom on an inversion center, while the distorted octahedron centered on the Cd atom lies on a twofold axis. The polymer chains are connected into undulating sheets by weak interchain N—H⋯N, N—H⋯O and O—H⋯N hydrogen bonds, which are also present between successive sheets. 相似文献