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1.
Simone Budow Khalil I. Shaikh Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(5):o246-o248
In the title compound, 2′‐deoxy‐7‐propynyl‐7‐deazaadenosine, C14H16N4O3, the torsion angle of the N‐glycosylic bond is anti [χ = −130.7 (2)°]. The sugar pucker of the 2′‐deoxyribofuranosyl moiety is C2′‐endo–C3′‐exo, 2T3 (S‐type), with P = 185.9 (2)° and τm = 39.1 (1)°, and the orientation of the exocyclic C4′—C5′ bond is −ap (trans). The 7‐substituted propynyl group is nearly coplanar with the heterocyclic base moiety. Molecules of the nucleoside form a layered network in which the heterocyclic bases are stacked head‐to‐tail with a closest distance of 3.197 (1) Å. The crystal structure of the nucleoside is stabilized by three intermolecular hydrogen bonds of types N—H⋯ O, O—H⋯ N and O—H⋯ O. 相似文献
2.
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
3.
Wen‐Qing Lin Xin Ming Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o379-o381
In the title compound [systematic name: 4‐amino‐7‐(β‐d ‐ribofuranosyl)‐7H‐pyrazolo[3,4‐d][1,2,3]triazine], C9H12N6O4, the torsion angle of the N‐glycosylic bond is high anti [χ = −83.2 (3)°]. The ribofuranose moiety adopts the C2′‐endo–C1′‐exo (2T1) sugar conformation (S‐type sugar pucker), with P = 152.4° and τm = 35.0°. The conformation at the C4′—C5′ bond is +sc (gauche,gauche), with the torsion angle γ = 52.0 (3)°. The compound forms a three‐dimensional network that is stabilized by several hydrogen bonds (N—H⋯O, O—H⋯N and O—H⋯O). 相似文献
4.
Frank Seela Anup M. Jawalekar Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o387-o389
In the title compound, C12H13N3O5, the conformation of the glycosylic bond is anti [torsion angle = −105.3 (2)°]. The 2′‐deoxyribofuranose moiety adopts an S‐type sugar pucker and the orientation of the exocyclic C—C bond is −sc (trans). 相似文献
5.
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
6.
Xiaohua Peng Hans Reuter Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(10):o593-o595
In 4‐chloro‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐7H‐pyrrolo[2,3‐d]pyrimidine‐2,4‐diamine, C11H14ClN5O3, the conformation of the N‐glycosylic bond is between anti and high‐anti [χ = −102.5 (6)°]. The 2′‐deoxyribofuranosyl unit adopts the C3′‐endo‐C4′‐exo (3T4) sugar pucker (N‐type) with P = 19.6° and τm = 32.9° [terminology: Saenger (1989). Landolt‐Börnstein New Series, Vol. 1, Nucleic Acids, Subvol. a, edited by O. Madelung, pp. 1–21. Berlin: Springer‐Verlag]. The orientation of the exocyclic C4′—C5′ bond is +ap (trans) with a torsion angle γ = 171.5 (4)°. The compound forms a three‐dimensional network that is stabilized by four intermolecular hydrogen bonds (N—H⋯O and O—H⋯N) and one intramolecular hydrogen bond (N—H⋯Cl). 相似文献
7.
Frank Seela Padmaja Chittepu Junlin He Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(12):o884-o886
In the title compound, 2‐(2‐deoxy‐2‐fluoro‐β‐d ‐arabinofuranosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione, C8H10FN3O5, the torsion angle of the N‐glycosylic bond is anti [χ = −125.37 (13)°]. The furanose moiety adopts the N‐type sugar pucker (3T2), with P = 359.2° and τm = 31.4°. The conformation around the C4′—C5′ bond is antiperiplanar (trans), with a torsion angle γ of 177.00 (11)°. A network is formed via hydrogen bonds from the nucleobases to the sugar residues, as well as through hydrogen bonds between the sugar moieties. 相似文献
8.
Frank Seela Padmaja Chittepu Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o231-o233
The title compound, C11H12F2N4O3, exhibits an anti glycosylic bond conformation, with a torsion angle χ = −117.8 (2)°. The sugar pucker is N‐type (C4′‐exo, between 3T4 and E4, with P = 45.3° and τm = 41.3°). The conformation around the exocyclic C—C bond is −ap (trans), with a torsion angle γ = −177.46 (15)°. The nucleobases are stacked head‐to‐head. The crystal structure is characterized by a three‐dimensional hydrogen‐bond network involving N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds. 相似文献
9.
Haozhe Yang Simone Budow‐Busse Henning Eickmeier Hans Reuter Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(12):1116-1120
The title compound {systematic name: 4‐amino‐5‐cyclopropyl‐7‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐7H‐pyrrolo[2,3‐d]pyrimidine}, C14H18N4O3, exhibits an anti glycosylic bond conformation, with the torsion angle χ = −108.7 (2)°. The furanose group shows a twisted C1′‐exo sugar pucker (S‐type), with P = 120.0 (2)° and τm = 40.4 (1)°. The orientation of the exocyclic C4′—C5′ bond is ‐ap (trans), with the torsion angle γ = −167.1 (2)°. The cyclopropyl substituent points away from the nucleobase (anti orientation). Within the three‐dimensional extended crystal structure, the individual molecules are stacked and arranged into layers, which are highly ordered and stabilized by hydrogen bonding. The O atom of the exocyclic 5′‐hydroxy group of the sugar residue acts as an acceptor, forming a bifurcated hydrogen bond to the amino groups of two different neighbouring molecules. By this means, four neighbouring molecules form a rhomboidal arrangement of two bifurcated hydrogen bonds involving two amino groups and two O5′ atoms of the sugar residues. 相似文献
10.
Krzysztof Ejsmont Andrzej A. Domaski Janusz B. Kyzio Jacek Zaleski 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):o368-o370
The crystal structure of the α isomer of trans‐4‐bromoazoxybenzene [systematic name: trans‐1‐(bromophenyl)‐2‐phenyldiazene 2‐oxide], C12H9BrN2O, has been determined by X‐ray diffraction. The geometries of the two molecules in the asymmetric unit are slightly different and are within ∼0.02 Å for bond lengths, ∼2° for angles and ∼3° for torsion angles. The azoxy bridges in both molecules have the typical geometry observed for trans‐azoxybenzenes. The crystal network contains two types of planar molecules arranged in columns. The torsion angles along the Ar—N bonds are only 7 (2)°, on either side of the azoxy group. 相似文献
11.
Wenqing Lin Kuiying Xu Henning Eickmeier Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):o195-o197
In the title compound, 4‐amino‐3‐propynyl‐1‐(β‐d ‐ribofuranosyl)‐1H‐pyrazolo[3,4‐d]pyrimidine methanol solvate, C13H15N5O4·CH3OH, the torsion angle of the N‐glycosylic bond is between anti and high‐anti [χ = −101.8 (5)°]. The ribofuranose moiety adopts the C3′‐endo (3T2) sugar conformation (N‐type) and the conformation at the exocyclic C—C bond is +sc (gauche, gauche). The propynyl group is out of the plane of the nucleobase and is bent. The compound forms a three‐dimensional network which is stabilized by several hydrogen bonds (O—H·O and O—H·N). The nucleobases are stacked head‐to‐tail. The methanol solvent molecule forms hydrogen bonds with both the nucleobase and the sugar moiety. 相似文献
12.
Frank Seela Padmaja Chittepu Yang He Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):o173-o176
In 2‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione (6‐aza‐2′‐deoxyuridine), C8H11N3O5, (I), the conformation of the glycosylic bond is between anti and high‐anti [χ = −94.0 (3)°], whereas the derivative 2‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐N4‐(2‐methoxybenzoyl)‐1,2,4‐triazine‐3,5(2H,4H)‐dione (N3‐anisoyl‐6‐aza‐2′‐deoxyuridine), C16H17N3O7, (II), displays a high‐anti conformation [χ = −86.4 (3)°]. The furanosyl moiety in (I) adopts the S‐type sugar pucker (2T3), with P = 188.1 (2)° and τm = 40.3 (2)°, while the sugar pucker in (II) is N (3T4), with P = 36.1 (3)° and τm = 33.5 (2)°. The crystal structures of (I) and (II) are stabilized by intermolecular N—H⋯O and O—H⋯O interactions. 相似文献
13.
G. Mazumdar M. De A. Mukhopadhyay S. K. Mazumdar N. Mazumder A. K. Das Edward E. Knaus 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):494-495
In the title compound, C14H19IN2O8, an almost planar heterocyclic base is oriented anti with respect to the puckered sugar moiety. The sugar pucker is C2′‐endo/C3′‐exo, the N‐glycosidic torsion angle is 166.4 (4)° and the conformation of O5′ is +sc. The molecules are linked by hydrogen bonds of the types N—H?O and O—H?O. 相似文献
14.
Yoriko Sonoda Yuji Kawanishi Midori Goto 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o311-o313
The title molecule, C18H12Cl4, lies about an inversion centre and the hexatriene chain is planar. The torsion angle of the single bond between the planes of the chain and the benzene ring is −8.6 (3)°. The dihedral angle between the planes defined by the chains of adjacent molecules is 50.0 (2)°. The shortest intermolecular distance between the Cl atoms is 3.514 (1) Å. The molecules are joined through π–π‐stacking and strong attractive Cl⃛Cl interactions. 相似文献
15.
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
16.
Frank Seela Ping Ding Xiaohua Peng Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o600-o602
The title compound, 2,4‐diamino‐5‐bromo‐7‐(2‐deoxy‐2‐fluoro‐β‐d ‐arabinofuranosyl)‐7H‐pyrrolo[2,3‐d]pyrimidine, C11H13BrFN5O3, shows two conformations of the exocyclic C4′—C5′ bond, with the torsion angle γ (O5′—C5′—C4′—C3′) being 170.1 (3)° for conformer 1 (occupancy 0.69) and 60.7 (7)° for conformer 2 (occupancy 0.31). The N‐glycosylic bond exhibits an anti conformation, with χ = −114.8 (4)°. The sugar pucker is N‐type (C3′‐endo; 3T4), with P = 23.3 (4)° and τm = 36.5 (2)°. The compound forms a three‐dimensional network that is stabilized by several intermolecular hydrogen bonds (N—H...O, O—H...N and N—H...Br). 相似文献
17.
Frank Seela Khalil I. Shaikh Henning Eickmeier 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):o151-o153
In the title compound, 2‐amino‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐3,7‐dihydropyrrolo[2,3‐d]pyrimidin‐4‐one, C11H14N4O4, the N‐glycosylic bond torsion angle, χ, is anti [−106.5 (3)°]. The 2′‐deoxyribofuranosyl moiety adopts the 3T4 (N‐type) conformation, with P = 39.1° and τm = 40.3°. The conformation around the exocyclic C—C bond is ap (trans), with a torsion angle, γ, of −173.8 (3)°. The nucleoside forms a hydrogen‐bonded network, leading to a close‐packed multiple‐layer structure with a head‐to‐head arrangement of the bases. The nucleobase interplanar O=C—C⋯NH2 distance is 3.441 (1) Å. 相似文献
18.
Ernesto Castro Luis E. Cuca Suarez Peter Siengalewicz Rene Gutmann Georg Czermak Peter Brueggeller 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):o467-o469
The structure of the title compound, C23H32O4, an arylalkanone isolated from the petroleum ether fraction of the ethanol extract of the bark of Virola venosa, has been established by NMR spectroscopy and, for the first time, by X‐ray structure analysis. Two independent molecules of the same enantiomer are present in the unit cell. Both molecules exhibit an intramolecular hydrogen bond, which can be correlated with a rare signal observed at 18.28 p.p.m. in the 1H NMR spectrum. The packing, in space group P1, is determined by a pseudo‐center of symmetry leading to a short intermolecular contact, which is present in one molecule but does not occur in the other. As a consequence, the O—C—C—O torsion angles [−16.9 (3) and −12.7 (3)°] through the ketone and its adjacent hydroxy group are significantly different in the two molecules. 相似文献
19.
Fabrizio Adani Enzo Montoneri Philip J. Squattrito 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):463-464
The title compound, C7H8FO6PS·H2O, contains both phosphonic and sulfonic acid functionalities. An extensive network of O—H?O hydrogen bonds is present in the crystal structure. The three acidic protons are associated with the phosphonate group. Two protons experience typical hydrogen‐bond contacts with the sulfonate‐O atoms, while the third has a longer covalent bond of 1.05 (3) Å to the phosphonate‐O atom and a short hydrogen‐bond contact of 1.38 (3) Å to the water O atom (all O—H?O angles are in the range 162–175°). The sulfonate group is positioned so that one S—O bond is nearly coplanar with the phenyl ring [torsion angle O—S—C—C ?8.6 (2)°]. The phosphonate group is oriented approximately perpendicular to the ring [torsion angle P—C—C—C 99.2 (2)°] with one P—O bond anti to the benzyl C—C bond. The molecules pack in layers in the b–c plane with the water molecules in between adjacent pairs of inverted layers. 相似文献
20.
Simone Budow Peter Leonard Henning Eickmeier Hans Reuter Frank Seela 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(3):o100-o102
The title compound [systematic name: 1‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐3‐iodo‐5‐nitro‐1H‐indole], C13H13IN2O5, exhibits an anti glycosylic bond conformation with a χ torsion angle of −114.9 (3)°. The furanose moiety shows a twisted C2′‐endo sugar pucker (S‐type), with P = 141.3° and τm = 40.3°. The orientation of the exocyclic C4′—C5′ bond is +ap (gauche, trans), with a γ torsion angle of 177.4 (2)°. The extended crystal structure is stabilized by hydrogen bonding and I...O contacts, as well as by stacking interactions. The O atoms of the nitro group act as acceptors, forming bifurcated hydrogen bonds within the ac plane. Additionally, the iodo substituent forms an interplanar contact with an O atom of the nitro group, and another contact with the O atom of the 5′‐hydroxy group of the sugar moiety within the ac plane is observed. These contacts can be considered as the structure‐determining factors for the molecular packing in the crystal structure. 相似文献