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1.
Paul C. Kline Hongqiu Zhao Bruce C. Noll Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):o215-o218
The title compound, also known as β‐erythroadenosine, C9H11N5O3, (I), a derivative of β‐adenosine, (II), that lacks the C5′ exocyclic hydroxymethyl (–CH2OH) substituent, crystallizes from hot ethanol with two independent molecules having different conformations, denoted (IA) and (IB). In (IA), the furanose conformation is OT1–E1 (C1′‐exo, east), with pseudorotational parameters P and τm of 114.4 and 42°, respectively. In contrast, the P and τm values are 170.1 and 46°, respectively, in (IB), consistent with a 2E–2T3 (C2′‐endo, south) conformation. The N‐glycoside conformation is syn (+sc) in (IA) and anti (−ac) in (IB). The crystal structure, determined to a resolution of 2.0 Å, of a cocrystal of (I) bound to the enzyme 5′‐fluorodeoxyadenosine synthase from Streptomyces cattleya shows the furanose ring in a near‐ideal OE (east) conformation (P = 90° and τm = 42°) and the base in an anti (−ac) conformation. 相似文献
2.
Wenhui Zhang Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(9):o484-o487
The title compound, C13H24O11·4H2O, (I), crystallized from water, has an internal glycosidic linkage conformation having ϕ′ (O5Gal—C1Gal—O1Gal—C4All) = −96.40 (12)° and ψ′ (C1Gal—O1Gal—C4All—C5All) = −160.93 (10)°, where ring‐atom numbering conforms to the convention in which C1 denotes the anomeric C atom, C5 the ring atom bearing the exocyclic hydroxymethyl group, and C6 the exocyclic hydroxymethyl (CH2OH) C atom in the βGalp and βAllp residues. Internal linkage conformations in the crystal structures of the structurally related disaccharides methyl β‐lactoside [methyl β‐d ‐galactopyranosyl‐(1→4)‐β‐d ‐glucopyranoside] methanol solvate [Stenutz, Shang & Serianni (1999). Acta Cryst. C 55 , 1719–1721], (II), and methyl β‐cellobioside [methyl β‐d ‐glucopyranosyl‐(1→4)‐β‐d ‐glucopyranoside] methanol solvate [Ham & Williams (1970). Acta Cryst. B 26 , 1373–1383], (III), are characterized by ϕ′ = −88.4 (2)° and ψ′ = −161.3 (2)°, and ϕ′ = −91.1° and ψ′ = −160.7°, respectively. Inter‐residue hydrogen bonding is observed between O3Glc and O5Gal/Glc in the crystal structures of (II) and (III), suggesting a role in determining their preferred linkage conformations. An analogous inter‐residue hydrogen bond does not exist in (I) due to the axial orientation of O3All, yet its internal linkage conformation is very similar to those of (II) and (III). 相似文献
3.
4.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o743-o745
The title compounds, C20H17NO3S, (I), and C19H15NO2S, (II), were prepared by the reaction of benzo[b]thiophene‐2‐carbaldehyde with (3,4,5‐trimethoxyphenyl)acetonitrile and (3,4‐dimethoxyphenyl)acetonitrile, respectively, in the presence of methanolic potassium hydroxide. In (I), the C=C bond linking the benzo[b]thiophene and the 3,4,5‐trimethoxyphenyl units has E geometry, with dihedral angles between the plane of the bridging unit and the planes of the two adjacent ring systems of 5.2 (3) and 13.1 (2)°, respectively. However, in (II), the C=C bond has Z geometry, with dihedral angles between the plane of the bridging unit and the planes of the adjacent benzo[b]thiophene and 3,4‐dimethoxyphenyl units of 4.84 (17) and 76.09 (7)°, respectively. There are no significant intermolecular hydrogen‐bonding interactions in the packing of (I) and (II). The packing is essentially stabilized via van der Waals forces. 相似文献
5.
Thomas E. Klepach Meredith Reed Bruce C. Noll Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(12):o601-o606
Methyl β‐allolactoside [methyl β‐d ‐galactopyranosyl‐(1→6)‐β‐d ‐glucopyranoside], (II), was crystallized from water as a monohydrate, C13H24O11·H2O. The βGalp and βGlcp residues in (II) assume distorted 4C1 chair conformations, with the former more distorted than the latter. Linkage conformation is characterized by ϕ′ (C2Gal—C1Gal—O1Gal—C6Glc), ψ′ (C1Gal—O1Gal—C6Glc—C5Glc) and ω (C4Glc—C5Glc—C6Glc—O1Gal) torsion angles of 172.9 (2), −117.9 (3) and −176.2 (2)°, respectively. The ψ′ and ω values differ significantly from those found in the crystal structure of β‐gentiobiose, (III) [Rohrer et al. (1980). Acta Cryst. B 36 , 650–654]. Structural comparisons of (II) with related disaccharides bound to a mutant β‐galactosidase reveal significant differences in hydroxymethyl conformation and in the degree of ring distortion of the βGlcp residue. Structural comparisons of (II) with a DFT‐optimized structure, (IIC), suggest a link between hydrogen bonding, pyranosyl ring deformation and linkage conformation. 相似文献
6.
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
7.
Ewa Rozycka‐Sokolowska Andrzej Borowski Bernard Marciniak 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(6):o209-o211
The structure of the title compound, C6H6OS, exhibits a flip‐type disorder of the thiophene ring [occupancy ratio = 0.848 (3):0.152 (3)], which is typical for many thiophene derivatives. The puckered thiophene ring is essentially coplanar with the plane formed by the non‐H atoms of the acetyl substituent, similar to its simple analogues, i.e. 3‐acetyl‐2‐carboxythiophene, 4‐acetyl‐3‐carboxythiophene and 3,5‐diacetyl‐2‐ethylamino‐4‐methylthiophene. In the crystal structure, molecules are connected by C—H...π hydrogen bonds, forming a sheet parallel to the (001) plane. Moreover, an inspection of the crystal lattice reveals that there are short S...O contacts connecting the molecules of adjacent sheets. Comparison of the title crystal structure with its simple 3‐methoxythiophene analogue shows a close similarity in the herringbone arrangement of molecules and in the presence of C—H...π interactions and S...O contacts. 相似文献
8.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o217-o218
The title compound, C16H12N2S, has been synthesized by base‐catalyzed condensation of 1‐methylindole‐3‐carboxaldehyde with thiophene‐3‐acetonitrile. The product assumes an approximately planar Z configuration. The molecule has a thienyl‐ring flip disorder. 相似文献
9.
All Solid State Chromium(III) Selective Potentiometric Sensor Based on 2‐(1‐(2‐((3‐(2‐Hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol 下载免费PDF全文
Pankaj Kumar Sanjeev Kumar Sapna Jain Bhawna Y. Lamba Girdhar Joshi Shefali Arora 《Electroanalysis》2014,26(10):2161-2167
Highly selective all solid state electrochemical sensor based on a synthesized compound i.e. 2‐(1‐(2‐((3‐(2‐hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol (I) as an ionophore has been prepared and investigated for the selective quantification of chromium(III) ions. The effect of various plasticizers, viz. dibutyl phosphonate (DBP), dibutyl(butyl) phosphonate (DBBP), nitrophenyl octyl ether (NPOE), tris‐(2‐ethylhexyl)phosphonate (TEP), tri‐butyl phosphonate (TBP), dioctyl phthalate (DOP), dioctyl sebacate (DOS), benzyl acetate (BA) and acetophenone (AP) along with anion excluders NaTPB (sodium tetraphenyl borate) and KClTPB (potassium(tetrakis‐4‐chlorophenyl)borate was also studied. The optimum composition of the best performing membrane contained (I):KClTPB:NPOE:PVC in the ratio 15 : 3 : 40 : 42 w/w. The sensor exhibited near Nernstian slope of 20.1±0.2 mV/decade of activity in the working concentration range of 1.2×10?7–1.0×10?1 M, and in a pH range of 3.8–4.5. The sensor exhibited a fast response time of 10 s and could be used for about 5 months without any considerable divergence in potentials. The proposed sensor showed very good selectivity over most of the common cations including Na+, Li+, K+, Cu2+, Sr2+, Ni2+, Co2+, Ba2+, Hg2+, Pb2+, Zn2+, Cs+, Mg2+, Cd2+, Al3+, Fe3+and La3+. The activity of Cr(III) ions was successfully determined in the industrial waste samples by using this sensor. 相似文献
10.
Nevzat Karaday ükriye akmak Mustafa Odabaolu Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o303-o305
The title 4,4′‐disubstituted diphenyl‐1,3‐triazines, C14H15N3, (I), C12H9ClFN3, (II), and C13H12FN3, (III), each contain a triazene group (–N=N—NH–) having an extended conformation. The dihedral angles between the two benzene rings in (I), (II) and (III) are 4.3, 3.4 and 6.5°, respectively. The molecules are almost entirely planar, with maximum deviations from the mean planes of 0.1087 (2), −0.1072 (7) and 0.1401 (3) Å, respectively. In each compound, the molecules are linked by N—H⋯N hydrogen bonds to form chains and pack similarly in the crystal structures. 相似文献
11.
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
12.
Alessandra Forni Julieta Gradinaru 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):o342-o344
The structure of the title S‐alkylated isothiosemicarbazide, C12H15N3OS, was determined by single‐crystal diffractometry and compared with the structures of other compounds containing the S‐alkylthiosemicarbazide moiety. Such structures cluster into two groups, according to the different orientation of the –SR group with respect to the hydrazine N atom of the thiosemicarbazide. The cis arrangement is preferred by most molecules in the solid state, in spite of the possibility of intramolecular N—H?N interactions in the opposite orientation. 相似文献
13.
Arthur D. Hendsbee Jason D. Masuda Adam Pirko 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(12):m391-m394
In the complex salt [η6‐1‐chloro‐2‐(pyrrolidin‐1‐yl)benzene](η5‐cyclopentadienyl)iron(II) hexafluoridophosphate, [Fe(C5H5)(C10H12ClN)]PF6, (I), the complexed cyclopentadienyl and benzene rings are almost parallel, with a dihedral angle between their planes of 2.3 (3)°. In a related complex salt, (η5‐cyclopentadienyl){2‐[η6‐2‐(pyrrolidin‐1‐yl)phenyl]phenol}iron(II) hexafluoridophosphate, [Fe(C5H5)(C16H17NO)]PF6, (II), the analogous angle is 5.4 (1)°. In both complexes, the aromatic C atom bound to the pyrrolidine N atom is located out of the plane defined by the remaining five ring C atoms. The dihedral angles between the plane of these five ring atoms and a plane defined by the N‐bound aromatic C atom and two neighboring C atoms are 9.7 (8) and 5.6 (2)° for (I) and (II), respectively. 相似文献
14.
Wenhui Zhang Qingquan Wu Allen G. Oliver Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):610-615
The crystal structure of methyl α‐d ‐mannopyranosyl‐(1→3)‐2‐O‐acetyl‐β‐d ‐mannopyranoside monohydrate, C15H26O12·H2O, ( II ), has been determined and the structural parameters for its constituent α‐d ‐mannopyranosyl residue compared with those for methyl α‐d ‐mannopyranoside. Mono‐O‐acetylation appears to promote the crystallization of ( II ), inferred from the difficulty in crystallizing methyl α‐d ‐mannopyranosyl‐(1→3)‐β‐d ‐mannopyranoside despite repeated attempts. The conformational properties of the O‐acetyl side chain in ( II ) are similar to those observed in recent studies of peracetylated mannose‐containing oligosaccharides, having a preferred geometry in which the C2—H2 bond eclipses the C=O bond of the acetyl group. The C2—O2 bond in ( II ) elongates by ~0.02 Å upon O‐acetylation. The phi (?) and psi (ψ) torsion angles that dictate the conformation of the internal O‐glycosidic linkage in ( II ) are similar to those determined recently in aqueous solution by NMR spectroscopy for unacetylated ( II ) using the statistical program MA′AT, with a greater disparity found for ψ (Δ = ~16°) than for ? (Δ = ~6°). 相似文献
15.
Frank Seela Xiaohua Peng Henning Eickmeier Hans Reuter 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(1):o94-o97
The structures of the isomeric nucleosides 4‐nitro‐1‐(β‐d ‐ribofuranosyl)‐1H‐indazole, C12H13N3O6, (I), and 4‐nitro‐2‐(β‐d ‐ribofuranosyl)‐2H‐indazole, C12H13N3O6, (II), have been determined. For compound (I), the conformation of the glycosylic bond is anti [χ = −93.6 (6)°] and the sugar puckering is C2′‐exo–C3′‐endo. Compound (II) shows two conformations in the crystalline state which differ mainly in the sugar pucker; type 1 adopts the C2′‐endo–C3′‐exo sugar puckering associated with a syn base orientation [χ = 43.7 (6)°] and type 2 shows C2′‐exo–C3′‐endo sugar puckering accompanied by a somewhat different syn base orientation [χ = 13.8 (6)°]. 相似文献
16.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o78-o80
(Z)‐3‐(1H‐Indol‐3‐yl)‐2‐(3‐thienyl)acrylonitrile, C15H10N2S, (I), and (Z)‐3‐[1‐(4‐tert‐butylbenzyl)‐1H‐indol‐3‐yl]‐2‐(3‐thienyl)acrylonitrile, C26H24N2S, (II), were prepared by base‐catalyzed reactions of the corresponding indole‐3‐carboxaldehyde with thiophene‐3‐acetonitrile. 1H/13C NMR spectral data and X‐ray crystal structures of compounds (I) and (II) are presented. The olefinic bond connecting the indole and thiophene moieties has Z geometry in both cases, and the molecules crystallize in space groups P21/c and C2/c for (I) and (II), respectively. Slight thienyl ring‐flip disorder (ca 5.6%) was observed and modeled for (I). 相似文献
17.
Synthesis and Biological Activity of 1‐(Substituted phenoxyacetoxy)‐1‐(pyridin‐2‐yl or thien‐2‐yl)methylphosphonates 下载免费PDF全文
A series of novel O,O‐dimethyl 1‐(substituted phenoxyacetoxy)‐1‐(pyridin‐2‐yl or thien‐2‐yl)methylphosphonates 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k , 6l , 6m , 6n and 7a , 7b , 7c , 7d were synthesized. Their structures were confirmed by IR, 1H NMR, mass spectroscopy, and elemental analyses. The results of preliminary bioassays show that some of the title compounds exhibit moderate to good herbicidal and fungicidal activities. For example, the title compounds 6a , 6c , 6l , 6m , and 7d possess 90–100% inhibition against most of the tested plants at the dosage of 1500 g ai/ha, whereas the title compounds 6b , 6g , 6h and 6n possess 92–100% inhibition against Fusarium oxysporum, Phyricularia grisea, Botrytis cinereapers, Gibberella zeae, Sclerotinia sclerotiorum, and Cercospora beticola at the concentration of 50 mg/L. 相似文献
18.
Wenhui Zhang Bruce C. Noll Anthony S. Serianni 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o578-o581
The β‐pyranose form, (III), of 3‐deoxy‐d ‐ribo‐hexose (3‐deoxy‐d ‐glucose), C6H12O5, crystallizes from water at 298 K in a slightly distorted 4C1 chair conformation. Structural analyses of (III), β‐d ‐glucopyranose, (IV), and 2‐deoxy‐β‐d ‐arabino‐hexopyranose (2‐deoxy‐β‐d ‐glucopyranose), (V), show significantly different C—O bond torsions involving the anomeric carbon, with the H—C—O—H torsion angle approaching an eclipsed conformation in (III) (−10.9°) compared with 32.8 and 32.5° in (IV) and (V), respectively. Ring carbon deoxygenation significantly affects the endo‐ and exocyclic C—C and C—O bond lengths throughout the pyranose ring, with longer bonds generally observed in the monodeoxygenated species (III) and (V) compared with (IV). These structural changes are attributed to differences in exocyclic C—O bond conformations and/or hydrogen‐bonding patterns superimposed on the direct (intrinsic) effect of monodeoxygenation. The exocyclic hydroxymethyl conformation in (III) (gt) differs from that observed in (IV) and (V) (gg). 相似文献
19.
Guillaume Journot Reinhard Neier Helen Stoeckli‐Evans 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(3):o119-o122
In the title compounds, C11H18N2, (II), and C13H20N2O, (III), the pyrrolidine rings have twist conformations. Compound (II) crystallizes with two independent molecules (A and B) in the asymmetric unit. The mean planes of the pyrrole and pyrrolidine rings are inclined to one another by 89.99 (11) and 89.35 (10)° in molecules A and B, respectively. In (III), the amide derivative of (II), the same dihedral angle is much smaller, at only 13.42 (10)°. In the crystal structure of (II), the individual molecules are linked via N—H...N hydrogen bonds to form inversion dimers, each with an R22(12) graph‐set motif. In the crystal structure of (III), the molecules are linked via N—H...O hydrogen bonds to form inversion dimers with an R22(16) graph‐set motif. 相似文献
20.
Marciela Scarpellini Ademir Neves Adailton J. Bortoluzzi Antnio C. Joussef 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):356-358
In the title mononuclear complex, [Cu(C5H9N3)(C10H15N5)](ClO4)2, the CuII centre is surrounded by two N‐donor ligands, which impose a square‐pyramidal environment on the metal. The new tridentate ligand [2‐(imidazol‐4‐yl)ethyl][(1‐methylimidazol‐2‐yl)methyl]amine (HISMIMA) lies in the basal plane, while the histamine ligand occupies the apical and one of the basal positions around the CuII ion. 相似文献