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1.
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
2.
Tetraammonium cadmium dihydrogenselenite(IV) diselenate(VI), (NH4)4Cd(HSeIVO3)2(SeVIO4)2, is the third example of a compound containing both hydrogen selenite and selenate anions, and has a new structure type. It contains kröhnkite‐like heteropolyhedral chains in which CdO6 octahedra are linked via bridging HSeO3 groups, having their remaining two trans apices decorated by SeO4 groups. The charge‐balancing NH4 groups are involved in weak hydrogen bonding, whereas the H atom of the HSeO3 group provides a strong hydrogen bond [O⋯O = 2.614 (5) Å]. The average Cd—O bond length is 2.298 Å. All atoms are on general positions except Cd (on ). Relations to the kröhnkite‐type compounds Na2Mg(SO3)·2H2O, Ba2CoCl2(SeO3)2 and Ba2Ca(HPO4)2(H2PO4)2, and to the mineral curetonite are discussed. Unit‐cell data are given for an isotypic MnII analogue. 相似文献
3.
Yasumitsu Matsuo Yoshihide Tokoyoda Junko Hatori Masaru Komukae Seiichiro Ikehata 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):i39-i40
The structure of thallium selenate, Tl2SeO4, in a paraelastic phase (above 661 K) has been analysed by Rietveld analysis of the X‐ray powder diffraction pattern. Atomic parameters based on the isomorphic K2SO4 crystal in the paraelastic phase were used as the starting model. The structure was determined in the hexagonal space group P63/mmc, with a = 6.2916 (2) Å and c = 8.1964 (2) Å. From the Rietveld refinement it was found that two orientations are possible for the SeO4 tetrahedra, in which one of their apices points randomly up and down with respect to [001]. One Tl atom lies at the origin with symmetry, the other Tl and one of the O atoms occupy sites with 3m symmetry, the Se atom is at a site with symmetry and the remaining O atom is at a site with m symmetry. Furthermore, it was also found that the Tl atoms display anomalously large positional disorder along [001] in the paraelastic phase. 相似文献
4.
Claude Didierjean Julien Marin Emmanuel Wenger Jean‐Paul Briand Andr Aubry Gilles Guichard 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o200-o203
X‐ray studies reveal that tert‐butyl (6S)‐6‐isobutyl‐2,4‐dioxopiperidine‐1‐carboxylate occurs in the 4‐enol form, viz. tert‐butyl (6S)‐4‐hydroxy‐6‐isobutyl‐2‐oxo‐1,2,5,6‐tetrahydropyridine‐1‐carboxylate, C14H23NO4, when crystals are grown from a mixture of dichloromethane and pentane, and has an axial orientation of the isobutyl side chain at the 6‐position of the piperidine ring. Reduction of the keto functionality leads predominantly to the corresponding β‐hydroxylated δ‐lactam, tert‐butyl (4R,6S)‐4‐hydroxy‐6‐isobutyl‐2‐oxopiperidine‐1‐carboxylate, C14H25NO4, with a cis configuration of the 4‐hydroxy and 6‐isobutyl groups. The two compounds show similar molecular packing driven by strong O—H⋯O=C hydrogen bonds, leading to infinite chains in the crystal structure. 相似文献
5.
Dmitrii S. Yufit Judith A. K. Howard 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(3):o141-o143
The crystal structures of (1R,1′S)‐2′,2′‐dichloro‐N‐(1‐phenylethyl)cyclopropane‐1′‐carboxamide, C12H13Cl2NO, (I), and (1R,1′R)‐2′,2′‐difluoro‐N‐(1‐phenylethyl)cyclopropane‐1′‐carboxamide, C12H13F2NO, (II), have been determined. Both crystals contain two independent molecules with different conformations of the phenylethyl groups. In the crystals of both compounds, the molecules are linked together by N—H⃛O hydrogen bonds, thus forming chains in the a direction. 相似文献
6.
John N. Low Justo Cobo Celeste Garcìa Manuel Melguizo Manuel Nogueras Adolfo Snchez Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):597-599
In the title compound, C10H9N3O5, which was formed by the reaction of 6‐amino‐2‐methoxy‐4(3H)‐pyrimidinone with dimethyl acetylenedicarboxylate, the molecules are linked by N—H?O hydrogen bonds [N?O 2.8974 (15) and 3.0300 (15) Å, and N—H?O 165 and 174°] into planar sheets built from alternating R22(8) and R66(42) rings. 相似文献
7.
Matthew R. Wood Thomas A. Brettell Roger A. Lalancette 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):m33-m35
The title salt, methyl (1R,2R,3S,5S,8S)‐3‐benzoyloxy‐8‐methyl‐8‐azabicyclo[3.2.1]octane‐2‐carboxylate tetrachloroaurate(III), (C17H22NO4)[AuCl4], has its protonated N atom intramolecularly hydrogen bonded to the O atom of the methoxycarbonyl group [N⋯O = 2.755 (6) Å and N—H⋯O = 136°]. Two close intermolecular C—H⋯O contacts exist, as well as five C—H⋯Cl close contacts. The [AuCl4]− anion was found to be distorted square planar. 相似文献
8.
Cocrystallization and configurations of myo‐inositol‐1,2‐l‐camphor acetals in two crystal structures
Graeme J. Gainsford Sylvia M. Baars Andrew Falshaw 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o169-o172
The inositol rings in (1S,2R,3R,4S,5S,6R,7S,8S,11S)‐myo‐inositol‐1,2‐camphor acetal {systematic name: (1R,2S,3S,4R,5S,6R)‐5,6‐[(1S,2S,4S)‐1,7,7‐trimethylbicyclo[2.2.1]heptane‐2,2‐diyldioxy]cyclohexane‐1,2,3,4‐tetrol}, C16H26O6, and (1R,2S,3S,4R,5R,6S,7R/S,8S,11S)‐myo‐inositol‐1,2‐camphor acetal trihydrate {systematic name: (1S,2R,3R,4S,5R,6S)‐5,6‐[(1S,4S,6R/S)‐1,7,7‐trimethylbicyclo[2.2.1]heptane‐2,2‐diyldioxy]cyclohexane‐1,2,3,4‐tetrol trihydrate}, C16H26O6·3H2O, adopt flattened chair conformations with the latter crystal containing two stereoisomers in a 0.684 (2):0.316 (2) ratio, similar to that found both in solution and by calculation. Both molecules pack in the crystals in similar two‐dimensional layers, utilizing strong O—H⋯O hydrogen bonds, with the trihydrate cell expanded to incorporate the additional hydrogen‐bonded water molecules. 相似文献
9.
Nicolas Pradeille Anthony Linden Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):o249-o252
The title compounds, O‐benzyl‐N‐(benzyloxycarbonyl)threonyl‐2,N‐dimethylalaninanilide, C30H35N3O5, and methyl (4R)‐4‐benzyloxy‐N‐(benzyloxycarbonyl)valyl‐2‐(methylalanyl)prolinate, C30H39N3O7, were obtained from the `azirine coupling' of the corresponding protected amino acids with 2,2,N‐trimethyl‐2H‐azirin‐3‐amine and methyl (4R)‐4‐(benzyloxy)‐N‐(2,2‐dimethyl‐2H‐azirin‐2‐yl)prolinate, respectively. The Aib unit in each molecule has the greatest turn‐ or helix‐inducing effect on the molecular conformation. Intermolecular N—H⋯O interactions link the molecules of the tripeptide into sheets and those of the dipeptide into extended chains. 相似文献
10.
Chune Dong Junlong Zhang Liangfu Zhang Zuolong Yu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):e21-e21
The crystal structure of the new chiral complex (1R,2R)‐1,2‐diphenyl‐1,2‐bis(8‐quinolinesulfonylamino)‐ ethylenediamine–acetone (1/1), C32H26N4O4S2.C3H6O, is reported. The conformation of the C32H26N4O4S2 (BQSDA) molecule is determined by a bifurcated N—H?N hydrogen‐bond system. The acetone of solvation is linked to the BQSDA molecule by an N—H?O hydrogen bond. 相似文献
11.
Luigi R Nassimbeni Hong Su 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o358-o361
The structures of bis[(R)‐(+)‐1‐phenylethylammonium] (2R,3R)‐(−)‐2,3‐di‐p‐toluoyloxybutanedioate methanol disolvate monohydrate, 2C8H12N+·C20H16O82−·2CH4O·H2O, (I), and bis(benzylammonium) (2R,3R)‐(−)‐2,3‐di‐p‐toluoyloxybutanedioate dihydrate, 2C7H10N+·C20H16O82−·2H2O, (II), exhibit extensive hydrogen bonding, with (N—)H⋯O and (O—)H⋯O distances in the ranges 2.716 (2)–2.929 (3) and 2.687 (2)–2.767 (2) Å, respectively, in (I), and 2.673 (2)–2.888 (2) and 2.785 (2)–2.931 (2) Å, respectively, in (II). The amine groups are protonated and the carboxylate groups of the tartrate anions are fully deprotonated. The conformation of the toluoyltartrate anion and its molecular parameters are similar in both structures. 相似文献
12.
John Nicolson Low Justo Cobo Braulio Insuasty Manuel Nogueras Angela Salcedo Adolfo Snchez 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o125-o128
The title compounds, 2‐(4‐bromophenyl)‐1,2‐dihydropyrimido[1,2‐a]benzimidazol‐4‐(3H)‐one, C16H12BrN3O, (IVa), and 4‐(4‐methylphenyl)‐3,4‐dihydropyrimido[1,2‐a]benzimidazol‐2‐(1H)‐one, C17H15N3O, (Vb), both form R(8) centrosymmetric dimers via N—H?N hydrogen bonds. The N?N distance is 2.943 (3) Å for (IVa) and 2.8481 (16) Å for (Vb), with the corresponding N—H?N angles being 129 and 167°, respectively. However, in other respects, the supramolecular structures of the two compounds differ. Both compounds contain different C—H?π interactions, in which the C—H?π(centroid) distances are 2.59 and 2.47 Å for (IVa) and (Vb), respectively (the latter being a short distance), with C—H?π(centroid) angles of 158 and 159°, respectively. The supramolecular structures also differ, with a short Br?O distance of 3.117 (2) Å in bromo derivative (IVa), and a C—H?O interaction with a C?O distance of 3.2561 (19) Å and a C—H?O angle of 127° in tolyl system (Vb). The dihydropyrimido part of (Vb) is disordered, with a ratio of the major and minor components of 0.9:0.1. The disorder consists of two non‐interchangeable envelope conformers, each with an equatorial tolyl group and an axial methine H atom. 相似文献
13.
A. Gueddi B. Mernari M. Giorgi M. Pierrot 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e426-e428
The reaction of the diazine ligand 3,5‐bis(2‐pyridinyl)‐1,3,4‐oxadiazole (pod, C12H8N4O), with Cu(CF3SO3)2 or Ni(ClO4)2 afforded the title complexes diaquabis[3,5‐bis(2‐pyridinyl)‐1,3,4‐oxadiazole‐N2,N3]copper(II) bis(trifluoromethanesulfonate), [Cu(pod)2(H2O)2](CF3SO3)2, and diaquabis[3,5‐bis(2‐pyridinyl)‐1,3,4‐oxadiazole‐N2,N3]nickel(II) diperchlorate, [Ni(pod)2(H2O)2](ClO4)2. Both complexes present a crystallographically centrosymmetric mononuclear cation structure which consists of a six‐coordinated CuII or NiII ion with two pod molecules acting as bidentate ligands and two axially coordinated water molecules. 相似文献
14.
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
15.
Nada Kouti‐Hulita Miroslav
egarac 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):o171-o173
In the crystal structure of (R)‐N,N‐diisopropyl‐3‐(2‐hydroxy‐5‐methylphenyl)‐3‐phenylpropylaminium (2R,3R)‐hydrogen tartrate, C22H32NO+·C4H5O6−, the hydrogen tartrate anions are linked by O—H⋯O hydrogen bonds to form helical chains built from (9) rings. These chains are linked by the tolterodine molecules via N—H⋯O and O—H⋯O hydrogen bonds to form separate sheets parallel to the (101) plane. 相似文献
16.
Jesus Bueno Manuel Melguizo M. Luisa Quijano John Nicolson Low 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o363-o366
The supramolecular structures of the isomeric compounds 5,7‐dimethoxyimidazo[1,2‐c]pyrimidine, C8H9N3O2, (I), and 7‐methoxy‐1‐methylimidazo[1,2‐a]pyrimidin‐5(1H)‐one, C8H9N3O2, (II), are determined by weak C—H⃛N and C—H⃛O hydrogen bonds in (I), which generate alternating linked centrosymmetric R(8) and R(10) rings that form a ribbon running parallel to the c axis, and by C—H⃛O bonds in (II), which link the molecules into sheets comprising centrosymmetric R(10) and R(22) rings. 相似文献
17.
Christian Neis Thomas Kradolfer Kaspar Hegetschweiler 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(6):632-637
Single crystals of (1,3‐diamino‐5‐azaniumyl‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)lithium(I) diiodide dihydrate, [Li(C6H16N3O3)(C6H15N3O3)]I2·2H2O or [Li(Htaci)(taci)]I2·2H2O (taci is 1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol), (I), bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)sodium(I) iodide, [Na(C6H15N3O3)2]I or [Na(taci)2]I, (II), and bis(1,3,5‐triamino‐1,3,5‐trideoxy‐cis‐inositol‐κ3O2,O4,O6)potassium(I) iodide, [K(C6H15N3O3)2]I or [K(taci)2]I, (III), were grown by diffusion of MeOH into aqueous solutions of the complexes. The structures of the Na and K complexes are isotypic. In all three complexes, the taci ligands adopt a chair conformation with axial hydroxy groups, and the metal cations exhibit exclusive O‐atom coordination. The six O atoms of the resulting MO6 unit define a centrosymmetric trigonal antiprism with approximate D3d symmetry. The interligand O...O distances increase significantly in the order Li < Na < K. The structure of (I) exhibits a complex three‐dimensional network of R—NH2—H...NH2—R, R—O—H...NH2—R and R—O—H...O(H)—H...NH2—R hydrogen bonds. The structures of the Na and K complexes consist of a stack of layers, in which each taci ligand is bonded to three neighbours via pairwise O—H...NH2 interactions between vicinal HO—CH—CH—NH2 groups. 相似文献
18.
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
19.
Jens Hartung Michaela Schwarz Ingrid Svoboda Hartmut Fuess 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):o682-o684
The geometry of racemic methyl 2‐(4‐methyl‐2‐thioxo‐2,3‐dihydrothiazol‐3‐yloxy)propanoate, C8H11NO3S2, (I), is characterized by a distorted heterocyclic five‐membered ring and an enantiomorphic N‐alkoxy substituent, which is inclined at an angle of −68.8° to the thiazolethione plane in (M)‐(I). The unit cell consists of a 1:1 ratio of R,P‐ and S,M‐configured molecules of (I). The combination of a P configuration at the N—O axis and an R configuration at the asymmetric propanoate Cβ atom on one side, and an S,M configuration on the other side, is considered to originate from steric interactions. The largest substituent at the asymmetric propanoate Cβ atom, i.e. the methoxycarbonyl group, resides above the methyl substituent; the medium‐sized propanoate γ‐methyl substituent points in the opposite direction with respect to the N—O bond, whereas the H atom is located above the C=S double bond of the thiazolethione subunit. 相似文献
20.
G. Mazumder M. De S. K. Mazumder A. Mukhopadhyay A. K. Das A. Van Aerschot 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(5):560-561
The title compound, 9(R)‐[6(R)‐hydroxymethyl‐1‐oxa‐4‐thiacyclohexan‐2‐yl]‐1,9‐dihydro‐6H‐purin‐6‐one–water (4/3), C10H12N4O3S·0.75H2O, crystallizes in the triclinic space group P1 with four molecules in the asymmetric unit and 0.75 waters of hydration per molecule. The structure was refined to an R value of 0.072 for 3382 observed reflections. The four crystallographically independent molecules are designated A, B, C and D. All four oxathiane rings adopt the chair conformation and the purine bases are in an anti orientation with respect to the sugar moieties. Molecules A and D and molecules C and B are base paired by a single hydrogen bond of the type N—H?N. These base pairs are again hydrogen bonded to their translated pairs in the direction of a cell diagonal. 相似文献