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1.
John Nicolson Low Justo Cobo Braulio Insuasty Henry Insuasty Manuel Nogueras Adolfo Snchez 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o103-o105
In both title compounds, i.e. 3‐methyl‐1,5‐diphenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H18N4, (I), and 5‐(4‐chlorophenyl)‐3‐methyl‐1‐phenyl‐1,6,7,8‐tetrahydropyrazolo[3,4‐b][1,4]diazepine, C19H17ClN4, (II), an N—H?N hydrogen bond links six molecules to form an R(30) ring. Compound (I) crystallizes in the R space group and (II) crystallizes in P with three molecules in the asymmetric unit. The molecule of (I) contains a disordered seven‐membered ring. 相似文献
2.
Franois Loiseau Reinhard Neier Gaël Labat Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o636-o638
In the title compound, C9H12Br2O3, a (tetrahydrofuran‐2‐ylidene)acetate, the double bond has the Z form. In the tetrahydrofuran group, the relative configuration of the Br atom in the 3‐position and the methyl group in the 5‐position is anti. The compound crystallizes with two independent molecules per asymmetric unit and, in the crystal structure, the individual molecules are linked to their symmetry‐equivalent molecules by C—H⋯O hydrogen bonds, so forming centrosymmetric hydrogen‐bonded dimers. 相似文献
3.
The structures of two conformationally similar 1,4‐dihydropyrimidines with a novel carbamoyl substitution, viz. 6‐methyl‐5‐(N‐methylcarbamoyl)‐4‐phenyl‐1,2,3,4‐tetrahydropyrimidine‐2‐thione monohydrate, C13H15N3OS·H2O, (I), and 4‐(4‐chlorophenyl)‐6‐methyl‐5‐(N‐methylcarbamoyl)‐1,2,3,4‐tetrahydropyrimidine‐2‐thione monohydrate, C13H14ClN3OS·H2O, (II), exhibit the structural features of 1,4‐dihydropyridine calcium channel blockers. In both structures, the pyrimidine ring adopts a flattened boat conformation and the carbamoyl side chain is in an extended conformation with an anticlinal orientation. The phenyl ring occupies a pseudo‐axial position with respect to the pyrimidine ring in these structures. Both compounds crystallize with one molecule of water, which participates in a two‐dimensional hydrogen‐bonding network. The molecules are linked into dimers by N—H·S hydrogen bonds in both structures. 相似文献
4.
A. Subbiah Pandi V. Rajakannan D. Velmurugan Masood Parvez Moon‐Jib Kim A. Senthilvelan S. Narasinga Rao 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o164-o167
N‐(2‐Chlorobenzyl)‐1,2,3,4‐tetrahydroisoquinoline‐1,3‐dione, C16H12ClNO2, crystallizes in P21/n with three crystallographically independent molecules in the asymmetric unit, which differ slightly in conformation, N‐(2‐bromo‐4‐methylphenyl)‐1,2,3,4‐tetrahydroisoquinoline‐1,3‐dione, C16H12BrNO2, crystallizes in P21/n with one molecule in the asymmetric unit andN‐(2,3‐dichlorophenyl)‐1,2,3,4‐tetrahydroisoquinoline‐1,3‐dione, C15H9Cl2NO2, crystallizes in P21/c with one molecule in the asymmetric unit. In all three structures, the heterocyclic rings adopt approximately planar conformations. The pyridine rings are orthogonal to the substituted phenyl rings. In all three structures, the crystal packing is stabilized by intermolecular C—H?O hydrogen bonds. 相似文献
5.
Jarno Kansikas Kaija Sipil 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1383-1385
In the synthesis of 1‐phenyl‐2‐phenylthio‐2‐(tetrahydropyran‐2‐ylthio)ethanol, C19H22O2S2, four diastereoisomers are formed. Two non‐centrosymmetric enantiomeric forms which crystallize in space groups P212121 and Pna21 are presented. The former has an intramolecular hydrogen bond between the hydroxyl group and the O atom of the tetrahydropyran ring. In the latter isomer, the hydroxyl group forms an intermolecular hydrogen bond to the O atom of the tetrahydropyranyl group of a neighbouring molecule, joining the molecules into chains in the c‐axis direction; the O?O distances are 2.962 (4) and 2.764 (3) Å, respectively. The tetrahydropyran rings are in chair conformations in both isomers and the S side chain has an equatorial orientation in the former, but an axial orientation in the latter molecule. 相似文献
6.
Tor Dahl 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):708-710
The partner molecules of N,N‐dimethylaniline–1,2,4,5‐tetracyanobenzene (1/1), C8H11N·C10H2N4, are stacked alternately in infinite columns. The N atom of the N,N‐dimethylaniline molecule has a partially tetrahedral character and the distance between neighbouring molecules in the stack is relatively short on the side where the lone‐pair electrons of this atom are located. Molecular‐packing analysis of this and three other complexes of N,N‐dimethylaniline shows that there is a close relationship between the strength of the intermolecular interaction on this side and the tetrahedral character of the N atom. 相似文献
7.
Chong‐Hyeak Kim Sueg‐Geun Lee 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m421-m423
The title compound, [Ni(C3H10N2)2(H2O)2](C6H6NO3S)2, contains alternating layers of sulfanilate anions and diaquabis(1,3‐propanediamine)nickel(II) cations. The Ni atom lies on an inversion centre and is hexacoordinated by the 1,3‐propanediamine ligands, which function as N,N′‐bidentate ligands, and the water molecules, which are in a trans arrangement. The sulfanilate anions are arranged in layers, with the sulfonate and amine groups directed towards opposite sides of the layer. The structure is stabilized by a network of hydrogen bonding between the O and N atoms of the sulfanilate anions, the water molecules, and the N atoms of the 1,3‐propanediamine ligands. 相似文献
8.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun P. R. Seshadri D. Thirumalai 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):821-824
10‐(4‐Fluorophenyl)‐3,3,6,6,9‐pentamethyl‐3,4,6,7,9,10‐hexahydroacridine‐1,8(2H,5H)‐dione, C24H28FNO2, (I), crystallizes with two crystallographically independent molecules (which differ slightly in conformation), while 10‐(4‐fluorophenyl)‐9‐propyl‐3,3,6,6‐tetramethyl‐3,4,6,7,9,10‐hexahydroacridine‐1,8(2H,5H)‐dione, C26H32FNO2, (II), crystallizes with one molecule per asymmetric unit. In both structures, the central ring in the acridine moiety is in a sofa conformation, while the outer rings adopt intermediate half‐chair/sofa conformations. The central pyridine ring is orthogonal to the substituted phenyl ring. In both structures, the packing of the crystal is stabilized by C—H?O intermolecular hydrogen bonds. 相似文献
9.
Shyamaprosad Goswami Reshmi Mukherjee Kumaresh Ghosh Ibrahim Abdul Razak S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):716-717
In the title compound, N‐(6‐chloro‐4‐oxo‐3,4‐dihydropteridin‐2‐yl)‐2,2‐dimethylpropanamide, C11H12ClN5O2, the rings in the pterin moiety are planar. The amide carbonyl O atom is in syn‐periplanar conformation while the C—N—C—C propanamide linkage is antiperiplanar. The N—H?N and N—H?O intermolecular hydrogen bonds transform the molecules into infinite chains. 相似文献
10.
Paul G. Jene Christopher G. Pernin James A. Ibers 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):730-734
The X‐ray structure of 1,2,4,5‐tetrahydroxybenzene (benzene‐1,2,4,5‐tetrol) monohydrate, C6H6O4·H2O, (I), reveals columns of 1,2,4,5‐tetrahydroxybenzene parallel to the b axis that are separated by 3.364 (12) and 3.453 (11) Å. Molecules in adjacent columns are tilted relative to each other by 27.78 (8)°. Water molecules fill the channels between the columns and are involved in hydrogen‐bonding interactions with the 1,2,4,5‐tetrahydroxybenzene molecules. The crystal structure of the adduct 1,2,4,5‐tetrahydroxybenzene–2,5‐dihydroxy‐1,4‐benzoquinone (1/1), C6H6O4·C6H4O4, (II), reveals alternating molecules of 1,2,4,5‐tetrahydroxybenzene and 2,5‐dihydroxy‐1,4‐benzoquinone (both lying on inversion centers), and a zigzag hydrogen‐bonded network connecting molecules in three dimensions. For compound (II), the conventional X‐ray determination, (IIa), is in very good agreement with the synchrotron X‐ray determination, (IIb). When differences in data collection temperatures are taken into account, even the displacement parameters are in very good agreement. 相似文献
11.
Andrew Hempel Norman Camerman Donald Mastropaolo Arthur Camerman 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1225-1227
The crystal structure of the title compound contains four 2,4‐diamino‐5‐methyl‐6‐[(3,4,5‐trimethoxyanilino)methyl]quinazoline molecules, two dimethyl sulfoxide molecules and three water molecules in the asymmetric unit, i.e. 4C19H23N5O3·2C2H6OS·3H2O. All four quinazoline molecules adopt trans,gauche conformations. An extensive hydrogen‐bond network involving N?N base‐pairing interactions, as well as the dimethyl sulfoxide and water molecules, stabilizes the crystal structure. 相似文献
12.
Cara L. Nygren M. E. T. Bragg John F. C. Turner 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):m4-m6
In the title compound, [ZrCl2(C14H12N)2(C4H8O)2]·1.5C6H6, the Zr atom is pseudo‐octahedral, with two Cl atoms in trans positions and two tetrahydrofuran molecules in cis positions. The two 3,6‐dimethylcarbazolyl ligands are in cis positions and are canted with respect to one another. The two Zr—N distances are 2.1148 (18) and 2.1236 (18) Å, and the N—Zr—N angle is 95.08 (7)°. The title compound crystallizes as the benzene solvate, with one of the benzene molecules positioned on an inversion center. 相似文献
13.
Canan Kazak Veysel T. Yilmaz Suleyman Servi Murat Koca Frank W. Heinemann 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):o348-o350
The title compounds, 1,3‐dibenzoylimidazolidine‐2‐thione, C17H14N2O2S, (I), and 1,3‐dibenzoyl‐3,4,5,6‐tetrahydropyrimidine‐2(1H)‐thione, C18H16N2O2S, (II), were obtained from the reactions of imidazolidine‐2‐thione and 1,4,5,6‐tetrahydropyrimidine‐2‐thiol, respectively, with benzoyl chloride. Compounds (I) and (II) contain, respectively, imidazolidinethione [C=S = 1.6509 (14) Å] and pyrimidinethione [C=S = 1.6918 (19) Å] moieties bonded to two benzoyl rings. The molecules of (I) exhibit C2 symmetry, the C=S bond lying along the twofold rotation axis, while the molecules of (II) have mirror symmetry (Cs). The imidazolidine ring in (I) is essentially planar, while the pyrimidine ring in (II) adopts a boat conformation. Molecules of (I) are linked by weak intermolecular C—H⋯O interactions, while molecules of (II) are held together by van der Waals interactions. 相似文献
14.
Eleonora Freire Sergio Baggio Juan Carlos Muoz Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):m221-m224
Two new nickel nitrates, diaquabis(3,4,7,8‐tetramethyl‐1,10‐phenanthroline‐κ2N,N′)nickel(II) dinitrate methanol solvate, [Ni(C16H16N2)2(H2O)2](NO3)2·CH4O, (I), and triaqua[2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine‐κ3N1,N2,N6]nickel(II) dinitrate trihydrate, [Ni(C18H12N6)(H2O)3](NO3)2·3H2O, (II), are reported. In both structures, the cation is octahedrally coordinated, to two bidentate 3,4,7,8‐tetramethyl‐1,10‐phenanthroline (tmp) and two water molecules in (I), and to one tridentate 2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine (tpt) and three water molecules in (II). Both structures are stabilized by extensive hydrogen‐bonding interactions. 相似文献
15.
Justyna A. Grzyb Alan J. Lough Robert A. Batey 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(10):o730-o732
In the crystal structure of the title compound, C13H13N3O, the C—Nimidazole bond length of 1.431 (3) Å is shorter than that observed [1.466 (6) Å] in the corresponding carbamoylimidazolium salt 3‐methyl‐1‐(1,2,3,4‐tetrahydroisoquinolin‐2‐ylcarbonyl)imidazolium iodide. A comparision of these compounds is used to highlight the structural differences that occur as a result of the imidazolium effect. Weak C—H⋯O hydrogen bonds link molecules into extended tapes in the a direction. 相似文献
16.
Lionel Salmon Pierre Thury Michel Ephritikhine 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):m246-m248
The title complex, bis(acetylacetonato‐κ2O,O′)[N,N′‐bis(3‐hydroxy‐2‐oxidobenzaldimino)‐2‐methyl‐1,2‐propanediamine‐κ4N,O,O′,N′]uranium(IV) tetrahydrofuran solvate, [U(C18H18N2O4)(C5H7O2)2]·C4H8O, is a rare example of a uranium(IV) complex with a compartmental Schiff base. The U atom is located in the N2O2 inner site of the hexadentate N,N′‐bis(3‐hydroxy‐2‐oxidobenzaldimino)‐2‐methyl‐1,2‐propanediamine group and is bound also to the two O atoms of both acetylacetonate moieties, which results in a dodecahedral coordination environment. Centrosymmetric dimers are formed through intermolecular hydrogen bonds that link the terminal uncoordinated hydroxy groups to one another and to the O atoms of the acetylacetonate ligands. 相似文献
17.
Viktor Vrbel Jozef Lehotay Drahomír Oktavec tefan Marchalín 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1073-1074
The crystal structure of the title compound, C20H23N3O7, consists of relatively isolated molecules. The substituted 1,4‐dihydropyridine ring adopts a flattened boat conformation. Both ester groups, at positions 3 and 5, have cis,cis geometry. The phenyl ring is nearly planar and is approximately perpendicular to the 1,4‐dihydropyridine ring (dihedral angle 87.70°). 相似文献
18.
Rafael Roggenbuck Markus Schürmann Hans Preut Peter Eilbracht 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e356-e356
The title compound, C12H16O4, (I), was prepared by oxidation of (5S*,6R*)‐1,7‐dioxadispiro[4.0.4.4]tetradecane‐2,8‐diol using silver(I) carbonate and posesses a cis configuration of the two five‐membered‐ring lactones fused spiro to the six‐membered carbocycle, which has a chair conformation. It represents an exceptional structure for bis‐tetrahydrofuran units, which are interesting building blocks in natural products. The synthesis, spectroscopic data and X‐ray structural analysis are described. The crystal contains discrete molecules separated by normal van der Waals distances. 相似文献
19.
Carl Henrik Grbitz 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o328-o330
The title compound, C20H21N3O3·0.75H2O, crystallizes as exceedingly thin fibers. The crystal packing arrangement is related to those of other hydrophobic dipeptides with phenylalanine residues, but the structure has pseudo‐tetragonal symmetry in an orthorhombic space group with four peptide molecules and three water molecules in the asymmetric unit. 相似文献
20.
Paul V. Bernhardt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):744-746
The title pendent‐arm macrocyclic hexaamine ligand binds stereospecifically in a hexadentate manner, and we report here its isomorphous NiII and ZnII complexes (both as perchlorate salts), namely (cis‐6,13‐dimethyl‐1,4,8,11‐tetraazacyclotetradecane‐6,13‐diamine‐κ6N)nickel(II) diperchlorate, [Ni(C12H30N6)](ClO4)2, and (cis‐6,13‐dimethyl‐1,4,8,11‐tetraaza‐cyclotetradecane‐6,13‐diamine‐κ6N)zinc(II) diperchlorate, [Zn(C12H30N6)](ClO4)2. Distortion of the N—M—N valence angles from their ideal octahedral values becomes more pronounced with increasing metal‐ion size and the present results are compared with other structures of this ligand. 相似文献