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1.
Sabahat
zcan Engin Kendi Meral Tunbilek Hakan Gker 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):459-460
The title compound, C21H23ClN4O2·0.5H2O, contains two independent molecules in the asymmetric unit. In each molecule the piperazine ring adopts a chair conformation; the deviations of the piperazine N atoms from the best plane through the remaining four C atoms are ?0.678 (3) and 0.662 (3) Å in molecule A, and 0.687 (3) and ?0.700 (3) Å in molecule B. The molecules are linked by two hydrogen bonds of the O—H?N type involving the O atom of the water molecule of crystallization. 相似文献
2.
John Nicolson Low Justo Cobo Manuel Nogueras Adolfo Snchez Braulio Insuasty Harlen Torres 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o39-o41
2,2‐Dimethyl‐5‐[3‐(4‐methylphenyl)‐2‐propenylidene]‐1,3‐dioxane‐4,6‐dione, C16H16O4, crystallizes in the triclinic space group , with two molecules in the asymmetric unit. These molecules and a centrosymmetrically related pair, linked together by weak C—H?O hydrogen bonds, form a tetramer. 5‐[3‐(4‐Chlorophenyl)‐2‐propenylidene]‐2,2‐dimethyl‐1,3‐dioxane‐4,6‐dione, C15H13ClO4, also crystallizes in the triclinic space group , with one molecule in the asymmetric unit. Centrosymmetrically related molecules are linked together by weak C—H?O hydrogen bonds to form dimers which are further linked by yet another pair of centrosymmetrically related C—H?O hydrogen bonds to form a tube which runs parallel to the a axis. 相似文献
3.
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
4.
Ivan Leban Boenna Golankiewicz Joanna Zeidler Gerald Giester Joe Kobe 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):o133-o135
In the title compound, C13H13N5O4·H2O (4,5′‐cyclowyosine·H2O), the cyclization forces a syn arrangement of the aglycon with respect to the sugar moiety. The ribofuranose part of the molecule displays a β‐d configuration with an envelope C1′‐endo pucker. The molecules are arranged in columns along the short a axis and are linked to water molecules through O—H?O and O—H?N hydrogen bonds. 相似文献
5.
Haibing Zhou Yi Yuan Albert S. C. Chan Teng‐Kuei Yang Rugang Xie 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):e57-e57
The asymmetric unit of C20H19NO4 contains two molecules with slightly different conformations. In the crystal, the molecules are linked by O—H?O and N—H?O hydrogen bonds [O?O 2.764 (3) and 2.811 (3) Å; N?O 2.907 (3) and 2.968 (3) Å] to form a two‐dimensional network. 相似文献
6.
John N. Low Debbie Cannon Antonio Quesada Antonio Marchal Manuel Melguizo Manuel Nogueras Adolfo Snchez Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):604-607
In the title compound, 2C10H15N5O4·0.5H2O, there are two independent molecules of the pyrimidinylisoleucine in general positions and a water molecule lying on a twofold rotation axis. The bond lengths within the organic moieties demonstrate significant polarization of the electronic structure. Each of the organic molecules participates in 12 intermolecular hydrogen bonds, of O—H?O and N—H?O types, while the water molecule acts as a double donor and as a double acceptor of O—H?O hydrogen bonds. The organic components are linked by the hydrogen bonds into a single three‐dimensional framework, reinforced by the water molecules. 相似文献
7.
Hugh W. Thompson Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o22-o23
The title keto acid, (+)‐23,24‐dinor‐3‐oxochol‐4‐en‐22‐oic acid, C22H32O3, forms carboxyl‐to‐ketone hydrogen‐bonding catemers [O?O = 2.699 (4) Å and O—H?O = 173°], linking molecules screw‐related in b. The four molecules in the cell form two parallel counter‐directional chains, screw‐related in a. Intermolecular C—H?O=C close contacts to different neighboring molecules were found for the ketone and the acid. 相似文献
8.
Solange M. S. V. Wardell James L. Wardell Mark F. Ward John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):865-867
Crystals of the title compound, C18H20N4O4, contain equal numbers of (R,R) and (S,S) molecules, but these are not precise enantiomorphs, neither are they related by crystallographic symmetry; in addition, each molecule exhibits approximate, but not exact, twofold rotational symmetry. There are intramolecular N—H?O hydrogen bonds [N?O 2.609 (4)–2.638 (5) Å; N—H?O 125–132°] and the molecules are linked into molecular ladders by C—H?O hydrogen bonds [C?O 3.306 (6)–3.386 (6) Å; C—H?O 146–160°]. 相似文献
9.
Raffaella Soave Riccardo Destro 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o507-o509
The asymmetric unit of the title compound, C22H31N3O4·H2O, incorporates one water molecule, which is hydrogen bonded to the 3‐oxo O atom of the indolizidinone system. The two rings of the peptidomimetic molecule are trans‐fused, with the six‐membered ring having a slightly distorted half‐chair conformation and the five‐membered ring having a perfect envelope conformation. The structure is stabilized by intermolecular O—H?O interactions between the water and adjacent peptide molecules, and by N—H?O interactions between the peptide molecules, which link the molecules into infinite chains. 相似文献
10.
Lian Ee Khoo Yiqun Zhang Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e350-e351
The title compound, C17H13NO4, exists as a planar molecule; adjacent molecules are linked by electrostatic C—H?O [C?O = 3.318 (4) and 3.455 (4) Å] interactions into a linear chain. 相似文献
11.
K. SethuSankar S. Banumathi R. Krishna D. Velmurugan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e479-e480
In the title compound, C13H16O4, the cyclohexene rings adopt a sofa conformation. Adjacent molecules are connected by C—H?O intermolecular interactions. Each molecule is characterized by O—H?O intramolecular hydrogen bonds. The anti arrangement of the enolic OH group and the carbonyl O atom in the solid state is similar to the anti arrangement of the NH and carbonyl groups in indigo. 相似文献
12.
Paul G. Jene James A. Ibers 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):246-249
In the crystalline state, the centrosymmetric molecule 1,2,4,5‐tetrakis(cyanomethyl)benzene, C14H10N4, has one cyanomethyl group in the benzene plane and one cyanomethyl group rotated 67.2 (2)° out of the benzene plane. Molecules of methyl 3,4,5‐triacetoxybenzoate, C14H14O8, form chains with each molecule twisted 89.6 (1)° from the preceding molecule. In this orientation, a close C—H?O contact is formed, with an H?O distance of 2.34 Å. The structure of 2‐(N‐phthalimidomethyl)benzoic acid, C16H11NO4, reveals hydrogen‐bonded dimers linked by the carboxyl groups of adjacent molecules. The O4?O3 distance is 2.636 (2) Å and the O4—H?O3 angle is 171 (2)°. 相似文献
13.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o1-o5
In the adduct 1,2‐bis(4‐pyridyl)ethane–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2), C12H12N2·2C20H18O3, the bipyridyl component lies across an inversion centre in P. The tris‐phenol molecules [systematic name: 4,4′,4′′‐(ethane‐1,1,1‐triyl)triphenol] are linked by O—H?O hydrogen bonds to form sheets built from R(38) rings, and symmetry‐related pairs of sheets are linked by the bipyridyl molecules via O—H?N hydrogen bonds to form open bilayers. Each bilayer is interwoven with two adjacent bilayers, forming a continuous three‐dimensional structure. In the adduct 1,2‐bis(4‐pyridyl)ethene–1,1,1‐tris(4‐hydroxyphenyl)ethane–methanol (1/1/1), C12H10N2·C20H18O3·CH4O, the molecules are linked by O—H?O and O—H?N hydrogen bonds into three interwoven three‐dimensional frameworks, generated by single spiral chains along [010] and [001] and a triple‐helical spiral along [100]. 相似文献
14.
Ivan Leban Lovro Seli
Toma Mesar Anton opar Tom olmajer 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):o367-o369
The molecular structure of the title tricyclic compound, C17H21NO4, which is the immediate precursor of a potent synthetic inhibitor {Lek157: sodium (8S,9R)‐10‐[(E)‐ethylidene]‐4‐methoxy‐11‐oxo‐1‐azatricyclo[7.2.0.03,8]undec‐2‐ene‐2‐carboxylate} with remarkable potency, provides experimental evidence for the previously modelled relative position of the fused cyclohexyl ring and the carbonyl group of the β‐lactam ring, which takes part in the formation of the initial tetrahedral acyl–enzyme complex. In this hydrophobic molecule, the overall geometry is influenced by C—H?O intramolecular hydrogen bonds [3.046 (4) and 3.538 (6) Å, with corresponding normalized H?O distances of 2.30 and 2.46 Å], whereas the molecules are interconnected through intermolecular C—H?O hydrogen bonds [3.335 (4)–3.575 (5) Å]. 相似文献
15.
Masood Parvez Govindaraji Senthil Veejendra K. Yadav 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):577-579
The stereoisomers of 7‐phenyl‐1‐oxa‐4‐thiaspiro[4.5]decan‐7‐ol, C14H18O2S, have the same stereochemistry at the C atom bearing an OH group, i.e. axial OH and equatorial phenyl groups. However, the acetal S and O atoms are axial and equatorial, respectively, in one isomer and reversed in the second. Furthermore, the crystals of one isomer are composed of hydrogen‐bonded molecules involving the hydroxyl H atom and the O atom of the five‐membered heterocyclic ring, with an O?O distance of 2.962 (3) Å, forming a polymeric chain along the b axis. The asymmetric unit of the other isomer is composed of two molecules, wherein hydroxyl H atoms and the O atoms of the five‐membered heterocyclic rings display intramolecular O—H?O hydrogen bonds with O?O separations of 2.820 (2) and 2.834 (2) Å. 相似文献
16.
Christopher Glidewell John N. Low Susan A. McWilliam Janet M. S. Skakle James L. Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o97-o99
In 2‐trifluoromethyl‐4‐nitroaniline, C7H5F3N2O2, (I), the molecules lie across a mirror plane in space group Pnma. The molecules are linked by paired N—H?O hydrogen bonds to form a C(8)[R(6)] chain of rings, pairs of which are linked into a molecular ladder by a single C—H?O hydrogen bond. The isomeric 3‐trifluoromethyl‐4‐nitroaniline, (II), has Z′ = 2 in space group P21/c. Each molecule is linked to four others by N—H?O hydrogen bonds to form sheets built from alternating R(12) and R(32) rings. 相似文献
17.
Pance Naumov Frosa Anastasova Michael G. B. Drew Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):e406-e407
In the title compound (5‐fluoroisatin), C8H4FNO2, the N atom of one molecule is linked to the amido‐O atom of an adjacent molecule across a center of symmetry by a cyclic hydrogen bond [N?O = 2.888 (4) Å]. 相似文献
18.
Ivan Leban Anton timac Joe Kobe Gerald Giester 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):890-891
In the title compound, C22H24N4O11, the N‐glycosidic torsion angles O′—C′—N—C and O′—C′—N—N are ?34.1 (6) and 148.8 (3)°, respectively. The molecule displays an α‐d configuration with the ribofuranose moiety in an O′‐exo–C′‐endo pucker. There are only weak C—H?O and C—H?N intra‐ and intermolecular interactions. 相似文献
19.
Dubravka Matkovi‐alogovi Jasminka Popovi Zora Popovi Igor Picek
eljka Soldin 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m39-m40
The title compound, [HgBr(C7H4NO4)(H2O)], was obtained by the reaction of an aqueous solution of mercury(II) bromide and pyridine‐2,6‐dicarboxylic acid (picolinic acid, dipicH2). The shortest bond distances to Hg are Hg—Br 2.412 (1) Å and Hg—N 2.208 (5) Å; the corresponding N—Hg—Br angle of 169.6 (1)° corresponds to a slightly distorted linear coordination. There are also four longer Hg—O interactions, three from dipicH? [2.425 (4) and 2.599 (4) Å within the asymmetric unit, and 2.837 (4) Å from a symmetry‐related molecule] and one from the bonded water molecule [2.634 (4) Å]. The effective coordination of Hg can thus be described as 2+4. The molecules are connected to form double‐layer chains parallel to the y axis by strong O—H?O hydrogen bonds between carboxylic acid groups of neighbouring molecules, and by weaker hydrogen bonds involving both H atoms of the water molecule and the O atoms of the carboxylic acid groups. 相似文献
20.
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