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1.
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   

2.
Methyl β‐D‐mannopyranosyl‐(1→4)‐β‐D‐xylopyranoside, C12H22O10, (I), crystallizes as colorless needles from water, with two crystallographically independent molecules, (IA) and (IB), comprising the asymmetric unit. The internal glycosidic linkage conformation in molecule (IA) is characterized by a ϕ′ torsion angle (O5′Man—C1′Man—O1′Man—C4Xyl; Man is mannose and Xyl is xylose) of −88.38 (17)° and a ψ′ torsion angle (C1′Man—O1′Man—C4Xyl—C5Xyl) of −149.22 (15)°, whereas the corresponding torsion angles in molecule (IB) are −89.82 (17) and −159.98 (14)°, respectively. Ring atom numbering conforms to the convention in which C1 denotes the anomeric C atom, and C5 and C6 denote the hydroxymethyl (–CH2OH) C atom in the β‐Xylp and β‐Manp residues, respectively. By comparison, the internal glycosidic linkage in the major disorder component of the structurally related disaccharide, methyl β‐D‐galactopyranosyl‐(1→4)‐β‐D‐xylopyranoside), (II) [Zhang, Oliver & Serriani (2012). Acta Cryst. C 68 , o7–o11], is characterized by ϕ′ = −85.7 (6)° and ψ′ = −141.6 (8)°. Inter‐residue hydrogen bonding is observed between atoms O3Xyl and O5′Man in both (IA) and (IB) [O3Xyl...O5′Man internuclear distances = 2.7268 (16) and 2.6920 (17) Å, respectively], analogous to the inter‐residue hydrogen bond detected between atoms O3Xyl and O5′Gal in (II). Exocyclic hydroxymethyl group conformation in the β‐Manp residue of (IA) is gauche–gauche, whereas that in the β‐Manp residue of (IB) is gauche–trans.  相似文献   

3.
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   

4.
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   

5.
Methyl β‐d ‐galactopyranosyl‐(1→4)‐α‐d ‐mannopyranoside methanol 0.375‐solvate, C13H24O11·0.375CH3OH, (I), was crystallized from a methanol–ethanol solvent system in a glycosidic linkage conformation, with ϕ′ (O5Gal—C1Gal—O1Gal—C4Man) = −68.2 (3)° and ψ′ (C1Gal—O1Gal—C4Man—C5Man) = −123.9 (2)°, where the ring is defined by atoms O5/C1–C5 (monosaccharide numbering); C1 denotes the anomeric C atom and C6 the exocyclic hydroxymethyl C atom in the βGalp and αManp residues, respectively. The linkage conformation in (I) differs from that in crystalline methyl α‐lactoside [methyl β‐d ‐galactopyranosyl‐(1→4)‐α‐d ‐glucopyranoside], (II) [Pan, Noll & Serianni (2005). Acta Cryst. C 61 , o674–o677], where ϕ′ is −93.6° and ψ′ is −144.8°. An intermolecular hydrogen bond exists between O3Man and O5Gal in (I), similar to that between O3Glc and O5Gal in (II). The structures of (I) and (II) are also compared with those of their constituent residues, viz. methyl α‐d ‐mannopyranoside, methyl α‐d ‐glucopyranoside and methyl β‐d ‐galactopyranoside, revealing significant differences in the Cremer–Pople puckering parameters, exocyclic hydroxymethyl group conformations and intermolecular hydrogen‐bonding patterns.  相似文献   

6.
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.
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   

8.
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 bc plane with the water mol­ecules in between adjacent pairs of inverted layers.  相似文献   

9.
The title compound, [Cu(C9H5N2O3)2(C2H6OS)2], consists of octahedrally coordinated CuII ions, with the 3‐oxo‐3,4‐dihydroquinoxaline‐2‐carboxylate ligands acting in a bidentate manner [Cu—O = 1.9116 (14) Å and Cu—N = 2.1191 (16) Å] and a dimethyl sulfoxide (DMSO) molecule coordinated axially via the O atom [Cu—O = 2.336 (5) and 2.418 (7) Å for the major and minor disorder components, respectively]. The whole DMSO molecule exhibits positional disorder [0.62 (1):0.38 (1)]. The octahedron around the CuII atom, which lies on an inversion centre, is elongated in the axial direction, exhibiting a Jahn–Teller effect. The ligand exhibits tautomerization by H‐atom transfer from the hydroxyl group at position 3 to the N atom at position 4 of the quinoxaline ring of the ligand. The complex molecules are linked through an intermolecular N—H...O hydrogen bond [N...O = 2.838 (2) Å] formed between the quinoxaline NH group and a carboxylate O atom, and by a weak intermolecular C—H...O hydrogen bond [3.392 (11) Å] formed between a carboxylate O atom and a methyl C atom of the DMSO ligand. There is a weak intramolecular C—H...O hydrogen bond [3.065 (3) Å] formed between a benzene CH group and a carboxylate O atom.  相似文献   

10.
The title 1,2‐diol derivative, C10H12O2, crystallizes with two independent but closely similar mol­ecules in the asymmetric unit. Only two of the four OH groups are involved in classical hydrogen bonding; the mol­ecules thereby associate to form chains parallel to the short c axis. The other two OH groups are involved in O—H⋯(C[triple‐bond]C) systems. Additionally, three of the four C[triple‐bond]C—H groups act as donors in C—H⋯O inter­actions. The 1,4‐diol derivative crystallizes with two independent half‐mol­ecules of the diol (each associated with an inversion centre) and one water mol­ecule in the asymmetric unit, C12H16O2·H2O. Both OH groups and one water H atom act as classical hydrogen‐bond donors, leading to layers parallel to the ac plane. The second water H atom is involved in a three‐centre contact to two C[triple‐bond]C bonds. One acetyl­enic H atom makes a very short `weak' hydrogen bond to a hydr­oxy O atom, and the other is part of a three‐centre system in which the acceptors are a hydroxy O atom and a C[triple‐bond]C bond.  相似文献   

11.
The title compund, [Fe(C5H6N)(C7H7O2)], features one strong intermolecular hydrogen bond of the type N—H...O=C [N...O = 3.028 (2) Å] between the amine group and the carbonyl group of a neighbouring molecule, and vice versa, to form a centrosymmetric dimer. Furthermore, the carbonyl group acts as a double H‐atom acceptor in the formation of a second, weaker, hydrogen bond of the type C—H...O=C [C...O = 3.283 (2) Å] with the methyl group of the ester group of a second neighbouring molecule at (x, −y − , z − ). The methyl group also acts as a weak hydrogen‐bond donor, symmetry‐related to the latter described C—H...O=C interaction, to a third molecule at (x, −y − , z + ) to form a two‐dimensional network. The cyclopentadienyl rings of the ferrocene unit are parallel to each other within 0.33 (3)° and show an almost eclipsed 1,1′‐conformation, with a relative twist angle of 9.32 (12)°. The ester group is twisted slightly [11.33 (8)°] relative to the cylopentadienyl plane due to the above‐mentioned intermolecular hydrogen bonds of the carbonyl group. The N atom shows pyramidal coordination geometry, with the sum of the X—N—Y angles being 340 (3)°.  相似文献   

12.
Methyl β‐l ‐lactoside, C13H24O11, (II), is described by glycosidic torsion angles ϕ (O5Gal—C1Gal—O4Glc—C4Glc) and ψ (C1Gal—O1Gal—C4Glc—C5Glc) of 93.89 (13) and −127.43 (13)°, respectively, where the ring atom numbering conforms to the convention in which C1 is the anomeric C atom and C6 is the exocyclic hydroxy­methyl (CH2OH) C atom in both residues (Gal is galactose and Glc is glucose). Substitution of l ‐Gal for d ‐Gal in the biologically relevant disaccharide, methyl β‐lactoside [Stenutz, Shang & Serianni (1999). Acta Cryst. C 55 , 1719–1721], (I), significantly alters the glycosidic linkage inter­face. In the crystal structure of (I), one inter‐residue (intra­molecular) hydrogen bond is observed between atoms H3OGlc and O5Gal. In contrast, in the crystal structure of (II), inter‐residue hydrogen bonds are observed between atoms H6OGlc and O5Gal, H6OGlc and O6Gal, and H3OGlc and O2Gal, with H6OGlc serving as a donor with two intra­molecular acceptors.  相似文献   

13.
The new supramolecular compound [H2bpp][{Cu(Hbpy)2}{α‐HP2W18O62}]·4H2O ( 1 ) (bpy = 4,4′‐bipyridine, bpp = 1,3‐bis(4‐pyridyl)propane) was synthesized hydrothermally and characterized byelemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction. In compound 1 , the cationic fragment [Cu(Hbpy)2]+ connects to the Dawson anion through a coordinating Cu←O bond, and the copper atom is coordinated by another polyoxoanion through a weak covalent bond with a Cu1–O26 distance of 2.879(2) Å, forming a polymeric chain. The bpy ligand in [Cu(Hbpy)2]+ adopts a monodentate coordination mode, the other nitrogen atom of the bpy ligand is protonated. The protonated Hbpy+ acts as hydrogen‐bond donor and constructs a two‐dimensional double‐sheet supramolecular network involving the one‐dimensional chains through the hydrogen bonds. The H2bpp2+ ion connects twoα‐HP2W18O626– clusters from two supramolecular networks through hydrogen bonds and creates a three‐dimensional supramolecular architecture. The thermal decomposition of 1 happens over a wide temperature range (450–800 °C), which indicates that it might include complicated oxidation–reduction processes.  相似文献   

14.
In the title compound, [Mn(C5H2N2O4)(C12H9N3)2]·H2O, the MnII centre is surrounded by three bidentate chelating ligands, namely, one 6‐oxido‐2‐oxo‐1,2‐dihydropyrimidine‐5‐carboxylate (or uracil‐5‐carboxylate, Huca2−) ligand [Mn—O = 2.136 (2) and 2.156 (3) Å] and two 2‐(2‐pyridyl)‐1H‐benzimidazole (Hpybim) ligands [Mn—N = 2.213 (3)–2.331 (3) Å], and it displays a severely distorted octahedral geometry, with cis angles ranging from 73.05 (10) to 105.77 (10)°. Intermolecular N—H...O hydrogen bonds both between the Hpybim and the Huca2− ligands and between the Huca2− ligands link the molecules into infinite chains. The lattice water molecule acts as a hydrogen‐bond donor to form double O...H—O—H...O hydrogen bonds with the Huca2− O atoms, crosslinking the chains to afford an infinite two‐dimensional sheet; a third hydrogen bond (N—H...O) formed by the water molecule as a hydrogen‐bond acceptor and a Hpybim N atom further links these sheets to yield a three‐dimensional supramolecular framework. Possible partial π–π stacking interactions involving the Hpybim rings are also observed in the crystal structure.  相似文献   

15.
The water content of the title compound, C13H24O10·3H2O, creates an extensive hydrogen‐bonding pattern, with all the hydroxyl groups of the disaccharide acting as hydrogen‐bond donors and acceptors. The water molecules are arranged in columns along the crystallographic b axis and form, together with one of the hydroxyl groups, infinite hydrogen‐bonded chains. The conformation of the disaccharide is described by glycosidic torsion angles of −38 and 18°.  相似文献   

16.
The title keto acid crystallizes as a solvate, C21H25FO4·C2H4O2, with two mol­ecules each of steroid and acetic acid per asymmetric unit. The former are approximately parallel, with opposite end‐to‐end orientation, and form translational carboxyl‐to‐ketone hydrogen‐bonding catemers [O⋯O = 2.679 (6) and 2.650 (5) Å, and O—H⋯O = 165 and 162°] that involve the 3‐ketone group and follow the a axis. The acetic acid mol­ecules are paired by hydrogen bonding, and neither they nor the F atom nor the 11‐ketone group play any overt role in the hydrogen‐bonding scheme of the steroid. Intermolecular C—H⋯O=C close contacts involving three different neighboring mol­ecules exist to the 11‐ketone group, the steroidal carboxyl group and one of the acetic acid molecules.  相似文献   

17.
In crystals of the title compound, C23H23N5O3S, the indole system is planar and the phenyl ring of the phenylsulfonyl group makes a dihedral angle with the best plane of the indole system of 77.18 (4)°. The olefinic bond connecting the azabicyclic and indole systems has Z geometry. The geometry adopted by the C=O bond with respect to the N—N bond is trans. The O atom of the carbonyl group of each molecule is hydrogen bonded to the hydrazidic H atom of an adjacent molecule to form an eight‐membered‐ring dimeric structure.  相似文献   

18.
The title compound, [Cu2(OH)2(C12H8N2)2(H2O)2][Cu(C10H9NO5S)2]·6H2O, is comprised of a copper‐centred complex cation and a copper‐centred complex anion; the cation lies about an inversion centre and in the anion the Cu atom lies on an inversion centre. In the doubly charged bridged dicopper cation, each Cu centre has distorted square‐pyramidal geometry. In the square‐planar dianion, two sulfonate ligands are trans coordinated to the Cu atom via a deprotonated hydroxyl O atom and an imine N atom, forming two six‐membered chelate rings. The structure is stabilized by an extensive hydrogen‐bond system and aromatic‐ring stacking interactions.  相似文献   

19.
In the title compounds, C12H20O6, (I), and C9H16O6, (II), the five‐membered furanose ring adopts a 4T3 conformation and the five‐membered 1,3‐dioxolane ring adopts an E3 conformation. The six‐membered 1,3‐dioxane ring in (I) adopts an almost ideal OC3 conformation. The hydrogen‐bonding patterns for these compounds differ substantially: (I) features just one intramolecular O—H...O hydrogen bond [O...O = 2.933 (3) Å], whereas (II) exhibits, apart from the corresponding intramolecular O—H...O hydrogen bond [O...O = 2.7638 (13) Å], two intermolecular bonds of this type [O...O = 2.7708 (13) and 2.7730 (12) Å]. This study illustrates both the similarity between the conformations of furanose, 1,3‐dioxolane and 1,3‐dioxane rings in analogous isopropylidene‐substituted carbohydrate structures and the only negligible influence of the presence of a 1,3‐dioxane ring on the conformations of furanose and 1,3‐dioxolane rings. In addition, in comparison with reported analogs, replacement of the –CH2OH group at the C1‐furanose position by another group can considerably affect the conformation of the 1,3‐dioxolane ring.  相似文献   

20.
In the title compound, 4‐amino‐7‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)‐5‐fluoro‐7H‐pyrrolo[2,3‐d]pyrimidine, C11H13FN4O3, the conformation of the glycosyl bond lies between anti and high anti [χ = −101.1 (3)°]. The furanose moiety adopts the S‐type sugar pucker (2T3), with P = 164.7 (3)° and τ = 40.1 (2)°. The extended structure is a three‐dimensional hydrogen‐bond network involving a C—H⋯F, two N—H⋯O and two O—H⋯O hydrogen bonds.  相似文献   

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