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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.
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
3.
Jun‐Gill Kang Jung‐Pyo Hong Il‐Hwan Suh 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):231-232
In the crystal structure of the title compound, 4‐cyano‐N‐(4‐methoxybenzylidene)phenylamine N‐oxide, C15H12N2O2, the 4‐methoxyphenyl is approximately coplanar with the nitrone moiety but significantly rotated with respect to the 4‐cyanophenyl moiety. The extent of this rotation is significantly different for the two crystallographically independent molecules of the asymmetric unit [dihedral angles of 19.4 (1) and 26.5 (1)°]. The geometry about the C=N bond is Z. The two molecules are related to one another by a pseudo inversion centre. 相似文献
4.
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
5.
Xinjiang Huang Genevieve H. Kuhn Vladimir N. Nesterov Boris B. Averkiev Benjamin Penn Mikhail Yu. Antipin Tatiana V. Timofeeva 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o624-o628
Syntheses and X‐ray structural investigations have been carried out for (E)‐(4‐hydroxyphenyl)(4‐nitrophenyl)diazene, C12H9N3O3, (Ia), (E)‐(4‐methoxyphenyl)(4‐nitrophenyl)diazene, C13H11N3O3, (IIIa), and (E)‐[4‐(6‐bromohexyloxy)phenyl](4‐cyanophenyl)diazene, C19H20BrN3O, (IIIc). In all of these compounds, the molecules are almost planar and the azobenzene core has a trans geometry. Compound (Ia) contains four and compound (IIIc) contains two independent molecules in the asymmetric unit, both in space group P (No. 2). In compound (Ia), the independent molecules are almost identical, whereas in crystal (IIIc), the two independent molecules differ significantly due to different conformations of the alkyl tails. In the crystals of (Ia) and (IIIa), the molecules are arranged in almost planar sheets. In the crystal of (IIIc), the molecules are packed with a marked separation of the azobenzene cores and alkyl tails, which is common for the solid crystalline precursors of mesogens. 相似文献
6.
Johan Wouters Bernadette Norberg Salvatore Guccione 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o69-o71
The crystal structures of 4‐methyl‐2‐[N‐(3,4‐methylenedioxybenzylidene)hydrazino]thiazole, C12H11N3O2S, and its reduction product 4‐methyl‐2‐[N‐(3,4‐methylenedioxybenzylidene)hydrazono]‐4,5‐dihydrothiazole, C12H13N3O2S, have been determined and compared. In the reduction product, the tautomer observed bears an H atom on the exocyclic N atom. Both compounds form hydrogen‐bonded dimers over centers of inversion. 相似文献
7.
Dun‐Ru Zhu Yan Xu Yong‐Jiang Liu You Song Yong Zhang Xiao‐Zeng You 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):242-243
In the title compound, 4‐(4H‐1,2,4‐triazol‐4‐yliminomethyl)phenol hemihydrate, C9H8N4O·0.5H2O or (I)·0.5H2O, molecules of (I) are arranged as layers running along the b axis through intermolecular O—H?N and C—H?O hydrogen bonds. These layers are stabilized by hydrogen‐bonded water molecules to form three‐dimensional networks. 相似文献
8.
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
9.
Caroline Charlier Bernadette Norberg Laurence Goossens Jean‐Pierre Hnichart Franois Durant 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):o648-o652
Three related compounds containing a pyrazole moiety with vicinal phenyl rings featuring a methylsulfonyl substituent are described, namely 3‐methyl‐1‐[4‐(methylsulfonyl)phenyl]‐5‐phenyl‐1H‐pyrazole, C17H16N2O2S, ethyl 1‐[4‐(methylsulfonyl)phenyl]‐5‐phenyl‐1H‐pyrazole‐3‐carboxylate, C19H18N2O4S, and 1‐[4‐(methylsulfonyl)phenyl]‐3‐[3‐(morpholino)phenoxymethyl]‐5‐phenyl‐1H‐pyrazole, C27H27N3O4S. The design of these compounds was based on celecoxib, a selective cyclooxygenase‐2 (COX‐2) inhibitor, in order to study the influence of various substituents on COX‐2 and 5‐lipoxygenase (5‐LOX) inhibition. 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.
Mohammed A. E. Shaban Ali Morgaan Hyungphil Chun Ivan Bernal 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e472-e473
Oxidative cyclization of 5‐ethyl‐3‐(4‐methoxybenzylidene)hydrazino‐1,2,4‐triazino[5,6‐b]indole gave the linearly annelated title compound, C19H16N6O. The skeleton is approximately planar, except for the ethyl group. 相似文献
12.
M. D. Crozet P. Vanelle M. Giorgi A. Gellis 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o496-o498
The title compounds, C13H15N3O5S and C11H10N2O4S2, respectively, both contain a phenylsulfonyl group connected, through a methylene bridge, to either a substituted nitroimidazole or nitro‐1,3‐thiazole ring. In the imidazole‐containing molecule, the nitro and sulfonyl groups are trans relative to the sulfonyl–methyl bond, while in the thiazole‐containing molecule, these substituents are cis. The stabilizing interactions within the crystals are also different between the two compounds. 相似文献
13.
I. I. Ponomarev A. Yu. Kovalevsky 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):260-262
Each of the three title compounds, namely 6,6′‐methylenebis(2‐methyl‐4H‐3,1‐benzoxazin‐4‐one), C19H14N2O4, 6,6′‐methylenebis(2‐trifluoromethyl‐4H‐3,1‐benzoxazin‐4‐one), C19H8F3N2O4, and 6,6′‐bi(2‐trifluoromethyl‐4H‐3,1‐benzoxazin‐4‐one), C18H6F6N2O4, contains two planar benzoxazinone fragments. In the first two compounds, these planes are virtually perpendicular to each other, while the third compound is planar overall. The electronic effects of the substituent groups on the oxazine moiety result in distortion of the bond angles at the C atoms of the C=O and C=N bonds, and in redistribution of electronic density in the oxazine rings. The latter leads to different bond lengths within this ring in the three molecules. All the molecules form stacks in their crystals with distances of 3.2–3.6 Å between adjacent molecules in a stack. 相似文献
14.
Russell G. Baughman Kenneth L. Martin Rajendra K. Singh James O. Stoffer 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(2):o103-o106
In 2,4‐dihydroxybenzaldehyde 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate {or 4‐[(2,4‐dinitrophenyl)hydrazonomethyl]benzene‐1,3‐diol N,N‐dimethylformamide solvate}, C13H10N4O6·C3H7NO, (X), 2,4‐dihydroxyacetophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylformamide solvate (or 4‐{1‐[(2,4‐dinitrophenyl)hydrazono]ethyl}benzene‐1,3‐diol N,N‐dimethylformamide solvate), C14H12N4O6·C3H7NO, (XI), and 2,4‐dihydroxybenzophenone 2,4‐dinitrophenylhydrazone N,N‐dimethylacetamide solvate (or 4‐{[(2,4‐dinitrophenyl)hydrazono]phenylmethyl}benzene‐1,3‐diol N,N‐dimethylacetamide solvate), C19H14N4O6·C4H9NO, (XII), the molecules all lack a center of symmetry, crystallize in centrosymmetric space groups and have been observed to exhibit non‐linear optical activity. In each case, the hydrazone skeleton is fairly planar, facilitated by the presence of two intramolecular hydrogen bonds and some partial N—N double‐bond character. Each molecule is hydrogen bonded to one solvent molecule. 相似文献
15.
Yuekun Zhao Madeleine Helliwell John A. Joule 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):714-715
Vilsmeier formylation of trans‐1‐(4‐methylphenylsulfonyl)‐2,5‐bis(pyrrol‐2‐yl)pyrrolidine leads to cleavage of the central ring then a reclosure resulting in the formation of trans‐N‐[2‐formyl‐4‐(5‐formylpyrrol‐2‐yl)‐4,5,6,7‐tetrahydroindol‐7‐yl]toluenesulfonamide, C21H21N3O4S. 相似文献
16.
Cassandra J. Martin David C. R. Hockless Max R. Taylor Lisandra L. Martin 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e549-e549
The previously unknown title compound, tetra‐μ‐acetato‐1:2κ2O;1:2κ2O:O′;2:3κ2O;2:3κ2O:O′‐diaqua‐1κO,3κO‐bis(μ‐2‐{[N‐ethyl‐N‐(2‐hydroxy‐5‐methylbenzyl)amino]methyl}‐1‐methyl‐1H‐benzimidazole)‐1κ3N3,N,O:2κO;3κ3N3,N,O:2κO‐trinickel(II) tetrahydrate, [Ni3(C18H22N3O)2(C2H3O2)4(H2O)2]·4H2O, (I), is a centrosymmetric linear trinuclear nickel(II) complex, where the Ni atoms are in an octahedral coordination and the ligand heteroatoms act so as to model amino acid residues. 相似文献
17.
Rebecca R. Conry Orville Green Mohammed Bakir 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o607-o609
A new polymorph of di‐2‐pyridyl ketone 4‐nitrophenylhydrazone [alternative name: N‐(dipyridin‐2‐ylmethylene)‐N′‐(4‐nitrophenyl)hydrazine], C17H13N5O2, isolated from the filtrate of a sonicated acetonitrile solution of dpknph and CdCl2, was found to crystallize in the monoclinic space group P21/c, in contrast to the known form which crystallizes in P21/n. The non‐coplanar molecules pack in parallel stacks without any intermolecular hydrogen‐bonding interactions. This packing pattern contrasts with the interlocked interdigitated packing seen in the previously known polymorph. 相似文献
18.
Vladimir N. Nesterov Elena A. Viltchinskaia 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):616-618
The structures of the title compounds, C15H13N3O4, (I), and C16H15N3O5 [IUPAC name: ethyl 6‐amino‐5‐cyano‐2‐methyl‐4‐(3‐nitrophenyl)‐4H‐pyrano‐3‐carboxylate], (II), are very similar, with the heterocyclic rings adopting boat conformations. The pseudo‐axial m‐nitrophenyl substituents are rotated by 84.0 (1) and 98.7 (1)° in (I) and (II), respectively, with respect to the four coplanar atoms of the boat. The dihedral angles between the phenyl rings and nitro groups are 12.1 (2) and 8.4 (2)° in (I) and (II), respectively. The two compounds have similar patterns of intermolecular N—H?O and N—H?N hydrogen bonding, which link molecules into infinite tapes along b . 相似文献
19.
Yao‐Cheng Shi Bei‐Bei Zhu Xiao‐Bi Jing 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):m559-m562
The molecules of N,N′‐bis(2‐pyridylmethyl)ferrocene‐1,1′‐diyldicarboxamide, [Fe(C12H11N2O)2], contain intramolecular N—H⋯N hydrogen bonds and are linked into sheets by three independent C—H⋯O hydrogen bonds. The molecules of the isomeric compound N,N′‐bis(3‐pyridylmethyl)ferrocene‐1,1′‐diyldicarboxamide lie across inversion centres, and the molecules are linked into sheets by a combination of N—H⋯N hydrogen bonds and π–π stacking interactions between pyridyl groups. 相似文献
20.
S. Renganayaki E. Subramanian S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):349-350
The aromatic ring of the cinnamic moiety in N‐benzyl‐2′‐iodocinnamanilide, C22H18INO, (I), and N‐benzyl‐2′‐iodo‐4′‐methyl‐2‐phenylcinnamanilide, C29H24INO, (II), makes a dihedral angle with the iodophenyl ring of 72.1 (2) and 81.0 (2)° in (I) and (II), respectively. In (I), molecules exist as discrete components, while in (II), they form infinite chains along the b axis, through I?O non‐bonded interactions. 相似文献