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1.
Ming Sun Alasdair C. Macculloch Thomas A. Hamor Richard T. Walker 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1492-1493
The pyrimidine ring of the title compound, C10H14N2O5S, is planar to within 0.024 (1) Å and makes an angle of 75.46 (10)° with the mean plane of the thiosugar ring. In terms of standard nucleoside nomenclature, this ring has the C3′‐endo conformation. The O5′—C5′—C4′—C3′ torsion angle is 166.5 (3)° and the glycosidic torsion angle S4′—C1′—N1—C2 is ?52.1 (2)° (syn). 相似文献
2.
Ming Sun Alasdair C. Macculloch Thomas A. Hamor Richard T. Walker 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):116-117
The pyrimidine ring of the title compound, C11H16N2O5S·H2O, is planar to within 0.026 (1) Å and makes an angle of 77.73 (8)° with the mean plane of the thiosugar ring. In terms of standard nucleoside nomenclature, this ring has a C1′‐exo,C2′‐endo conformation. The O5′—C5′—C4′—C3′ torsion angle is ?167.4 (2)° and the glycosidic S4′—C1′—N1—C2 torsion angle is ?101.8 (2)° (anti). 相似文献
3.
Maciej Bujak Jacek Zaleski Victor Prezhdo Boris Uspenskiy 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o76-o77
The title molecule, C11H12O3, is almost planar, with an average deviation of the C and O atoms from the least‐squares plane of 0.146 (4) Å. The geometry about the C=C bond is trans. The phenyl ring and –COOCH3 group are twisted with respect to the double bond by 9.3 (3) and 5.6 (5)°, respectively. The endocyclic angle at the junction of the propenoate group and the phenyl ring is decreased from 120° by 2.6 (2)°, whereas two neighbouring angles around the ring are increased by 2.3 (2) and 0.9 (2)°. This is probably associated with the charge‐transfer interaction of the phenyl ring and –COOCH3 group through the C=C double bond. The molecules are joined together through C—H?O hydrogen bonds between the methoxy and ester groups to form characteristic zigzag chains extended along the c axis. 相似文献
4.
Anthony J. Burke Helmut W. Schmalle Bernard A. Brady W. Ivo O'Sullivan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):484-486
The title compound, C17H14O4, is an unprecedented new synthetic isoaurone‐type enol ether that has the E configuration. The planar furanone ring is fused to a methoxybenzene ring system, with an interplanar angle of 175.7 (1)°. Due to this ring fusion, the six‐membered ring has a significant amount of ring strain, as shown by the internal ring angle range of 115.8 (1)–124.7 (1)°, whereas the vinylic phenyl ring has internal angles between 119.7 (1) and 120.2 (1)°. The molecules form infinite hydrogen‐bonding layers along the b direction of the form C—H?O, where the keto O atom acts as a bifurcated acceptor. These layers are connected along the c direction by another hydrogen bond with a methoxy H atom as donor. In addition to this connection, the layers are stacked via centres of symmetry by a pair of symmetry‐related benzofuranone ring systems. 相似文献
5.
Judith C. Gallucci Rajendrakumar Reddy Gadikota Todd L. Lowary 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):e365-e365
The crystal structure of the title compound, C20H17NO4S, (I), was determined in order to compare the solution and solid‐state conformations. The molecule was synthesized as a building block for incorporation into oligosaccharides comprised of conformationally restricted furanose residues. The furanose ring adopts an envelope conformation with the ring O atom displaced above the plane (an OE conformation). The pseudorotational phase angle (P) is 88.6° and the puckering amplitude (τm) is 31.5°. The C2—C1—S—C(Ph) torsion angle is ?163.2 (2)°, which places the aglycone in the exo‐anomeric effect preferred position. The C1—S—C14 bond angle is 99.02 (13)° and the plane of the cresyl moiety is oriented nearly parallel to the four in‐plane atoms of the furanose ring envelope. The orientation about the C4—C5 bond is gauche–gauche [Bock & Duus (1994). J. Carbohydr. Chem. 13 , 513–543]. 相似文献
6.
Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Hoong‐Kun Fun Tarun K. Sarkar Sankar Basak Gur Dayal Nigam 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1116-1117
In the title compound, C16H19ClN2O4, the pyridine ring is nearly planar, the piperidine ring is non‐planar and the cyclohexane ring adopts a screw‐boat conformation. The carboxylate group makes a dihedral angle of 80.9 (2)° with the least‐squares plane through the cyclohexane ring. 相似文献
7.
K. Sethu Sankar S. Kannadasan D. Velmurugan P. C. Srinivasan S. Shanmuga Sundara Raj H.‐K. Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(5):o277-o279
The title compound, C28H27N3O4S, crystallizes in the centrosymmetric space group P21/n, with one molecule in the asymmetric unit. In the indole ring, the dihedral angle between the fused rings is 3.6 (1)°. The phenyl ring of the sulfonyl substituent makes a dihedral angle of 79.2 (1)° with the best plane of the indole moiety. The phenyl ring of the dimethylaminophenyl group is orthogonal to the phenyl ring of the phenylsulfonyl group. The dihedral angle formed by the weighted least‐squares planes through the pyrrole ring and the phenyl ring of the dimethylaminophenyl group is 7.8 (1)°. The molecular structure is stabilized by C—H?O and C—H?N interactions. 相似文献
8.
Ying Fu Yin‐Xia He Hong‐Xia Hou Wen‐Bo Zhu Hu‐Lin Li Chao Wu Fang‐Yan Xian 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(3):282-284
2,2′‐Anhydro‐1‐(3′,5′‐di‐O‐acetyl‐β‐D‐arabinofuranosyl)uracil, C13H14N2O7, was obtained by refluxing 2′,3′‐O‐(methoxymethylene)uridine in acetic anhydride. The structure exhibits a nearly perfect C4′‐endo (4E) conformation. The best four‐atom plane of the five‐membered furanose ring is O—C—C—C, involving the C atoms of the fused five‐membered oxazolidine ring, and the torsion angle is only −0.4 (2)°. The oxazolidine ring is essentially coplanar with the six‐membered uracil ring [r.m.s. deviation = 0.012 (5) Å and dihedral angle = −3.2 (3)°]. The conformation at the exocyclic C—C bond is gauche–trans which is stabilized by various C—H...π and C—O...π interactions. 相似文献
9.
Zao‐Zao Qiu Xin‐Ping Hui Peng‐Fei Xu 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):o475-o476
The structure of the title compound, C22H24N2O9S2, is described. This compound consists of a sugar ring and a heterocyclic base linked unusually by an S atom. The sugar is in a 4C1 chair conformation and forms dihedral angles of 49.54 (4) and 33.42 (5)° with the thiadiazole and phenyl rings, respectively. The S atom occupies an equatorial position of the sugar ring and lies 1.807 (2) Å out of the corresponding mean plane. 相似文献
10.
Urmila H. Patel Chaitanya G. Dave Mukesh M. Jotani Hetal C. Shah 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(1):o30-o32
In the title compound, C23H20N2O2S, the central thienopyridine ring system is essentially planar, the dihedral angle between the planes of the two rings being 0.3 (2)°. The terminal ethyl carboxylate group is twisted by 26.7 (3)° away from the central ring system. A short intramolecular hydrogen bond involving the amino N atom and the carbonyl O atom [N⋯O = 2.806 (4) Å] forms a pseudo‐six‐membered ring. Significant intermolecular C—H⋯N, C—H⋯O and C—H⋯π interactions contribute strongly to the stability of the structure, along with weak π–π‐stacking interactions. 相似文献
11.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(2):o135-o136
In the title compound, C23H21N3O3, the indole ring is planar and the phenyl ring of the benzyl group makes a dihedral angle with the best plane of the indole ring of 73.77 (4)°. The double bond connecting the azabicyclic and indole moieties has Z geometry. 相似文献
12.
Ya‐Ling Liu Pei Zou Hao Wu Min‐Hao Xie Shi‐Neng Luo 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(9):o338-o340
The title compound, C16H24O10·0.11H2O, is a key intermediate in the synthesis of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (18F‐FDG), which is the most widely used molecular‐imaging probe for positron emission tomography (PET). The crystal structure has two independent molecules (A and B) in the asymmetric unit, with closely comparable geometries. The pyranose ring adopts a 4C1 conformation [Cremer–Pople puckering parameters: Q = 0.553 (2) Å, θ = 16.2 (2)° and ϕ = 290.4 (8)° for molecule A, and Q = 0.529 (2) Å, θ =15.3 (3)° and ϕ = 268.2 (9)° for molecule B], and the dioxolane ring adopts an envelope conformation. The chiral centre in the dioxolane ring, introduced during the synthesis of the compound, has an R configuration, with the ethoxy group exo to the mannopyranose ring. The asymmetric unit also contains one water molecule with a refined site‐occupancy factor of 0.222 (8), which bridges between molecules A and B via O—H...O hydrogen bonds. 相似文献
13.
14.
Julio Duque Hctor Novoa de Armas Ramn Poms Hernndez Margarita Surez Navarro Estael Ochoa Rodríguez Esperanza Salfrn Yamila Verdecia Reyes Norbert. M Blaton Oswald M. Peeters Camiel J. De Ranter 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1346-1347
In the title compound, C28H38N4O6, the 4‐aryl substituent occupies a pseudo‐axial position approximately orthogonal to the plane of the dihydropyridine ring [88.1 (3)°]. The dihydropyridine ring adopts a flattened boat conformation. The H atom on the pyridine N atom is involved in a bifurcated intramolecular hydrogen bond, the acceptors being the N atoms of the two piperidylmethyl groups [N?N 2.629 (4) and 2.695 (4) Å]. 相似文献
15.
Hoong‐Kun Fun R. Sankaranarayanan D. Velmurugan S. Shanmuga Sundara Raj G. Babu P. T. Perumal 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):475-476
In the title compound, C26H22N2O2S, the tetrahydropyridine ring has a conformation intermediate between half‐chair and sofa. The tetrahydroquinoline mean plane makes a dihedral angle of 73.3 (1)° with the cyclopentene ring, which adopts an envelope conformation, and an angle of 45.45 (4)° with the indole best plane. The dihedral angle between the benzene and pyrrole rings is 2.6 (1)°. The orientations of the phenyl ring on the sulfonyl group and of the indole are governed by weak C—H?O interactions. The packing of the molecule in the solid state is stabilized by C—H?O and C—H?N hydrogen bonds. 相似文献
16.
Jing‐Kun Xu Shou‐Zhi Pu Tian‐She Yang Ru‐Ji Wang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o568-o570
The title compound, C23H22F6O4S2, a photochromic dithienylethene, is a promising material for optical storage and other optoelectrical devices. The molecule adopts a photoactive antiparallel conformation in the crystalline state. The distance between the two reactive C atoms which are involved in potential ring closure is 3.829 (4) Å. The dihedral angles between the central cyclopentene ring and the adjacent thiophene rings are 55.38 (7) and 54.81 (9)°. The colourless crystals turn magenta when exposed to UV radiation and the process is reversible. 相似文献
17.
L. Govindasamy D. Velmurugan V. Raghukumar Il‐Hawn Suh V. T. Ramakrishnan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):80-81
In the title compound, C29H30N6, the naphthyridine ring is almost planar with a dihedral angle of 5.4 (1)° between the pyridyl rings. The dihedral angles between the naphthyridine system and the diethylaminophenyl, phenyl and pyrrolidine rings are 53.1 (1), 19.8 (1) and 20.9 (1)°, respectively. The pyrrolidine ring adopts a half‐chair conformation. The molecule is stabilized by weak C—H?N interactions. 相似文献
18.
Wenhui Zhang Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(1):o7-o11
Methyl β‐d ‐galactopyranosyl‐(1→4)‐β‐d ‐xylopyranoside, C12H22O10, (II), crystallizes as colorless needles from water with positional disorder in the xylopyranosyl (Xyl) ring and no water molecules in the unit cell. The internal glycosidic linkage conformation in (II) is characterized by a ϕ′ torsion angle (C2′Gal—C1′Gal—O1′Gal—C4Xyl) of 156.4 (5)° and a ψ′ torsion angle (C1′Gal—O1′Gal—C4Xyl—C3Xyl) of 94.0 (11)°, where the ring atom numbering conforms to the convention in which C1 denotes the anomeric C atom, and C5 and C6 denote the hydroxymethyl (–CH2OH) C atoms in the β‐Xyl and β‐Gal residues, respectively. By comparison, the internal linkage conformation in the crystal structure of the structurally related disaccharide, methyl β‐lactoside [methyl β‐d ‐galactopyranosyl‐(1→4)‐β‐d ‐glucopyranoside], (III) [Stenutz, Shang & Serianni (1999). Acta Cryst. C 55 , 1719–1721], is characterized by ϕ′ = 153.8 (2)° and ψ′ = 78.4 (2)°. A comparison of β‐(1→4)‐linked disaccharides shows considerable variability in both ϕ′ and ψ′, with the range in the latter (∼38°) greater than that in the former (∼28°). Inter‐residue hydrogen bonding is observed between atoms O3Xyl and O5′Gal in the crystal structure of (II), analogous to the inter‐residue hydrogen bond detected between atoms O3Glc and O5′Gal in (III). The exocyclic hydroxymethyl conformations in the Gal residues of (II) and (III) are identical (gauche–trans conformer). 相似文献
19.
Süheyla
zbey Nuray Ulusoy Engin Kendi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):222-224
In the title compounds, C15H12N4OS, (I), and C14H10N4OS, (II), the thiadiazine ring adopts a skew‐boat conformation, while the triazole and furyl rings are essentially planar. The phenyl group is twisted by 33.5 (2) and 47.9 (1)° out of the triazole‐ring plane in (I) and (II), respectively. 相似文献
20.
R. Sankaranarayanan D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):726-727
In the title compound, C29H30N6O, the naphthyridine moiety is planar with a dihedral angle between the fused rings of 1.9 (1)°. The phenol ring is nearly coplanar, while the diethylaminophenyl substituent is orthogonal to the central naphthyridine ring and the pyrrolidine ring makes an angle of 11.2 (1)° with it. The O atom of the hydroxy substituent is coplanar with the phenyl ring to which it is attached. The molecular structure is stabilized by a C—H?N‐type intramolecular hydrogen bond and the packing is stabilized by intermolecular C—H?π, O—H?N and N—H?O hydrogen bonds. 相似文献