VERY STRONG HYDROGEN BONDING OF PHOSPHATES: X-RAY CRYSTAL STRUCTURES OF 1,2,3-BENZOTRIAZOLIUM DIHYDROGEN PHOSPHATE [C6H4N3H2 +][H2PO− 4] AND 1,3-BENZIMIDAZOLIUM DIHYDROGEN PHOSPHATE [C7H5N2H2 +][H2PO− 4]

1988 ◽  
Vol 35 (1-2) ◽  
pp. 141-149 ◽  
Author(s):  
John Emsley ◽  
Naser M. Reza ◽  
Helen M. Dawes ◽  
Michael B. Hursthouse ◽  
Reiko Kuroda
Keyword(s):  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Dihydrogen Phosphate ◽  
X Ray

scholarly journals The crystal structures and mechanical properties of the uranyl carbonate minerals roubaultite, fontanite, sharpite, widenmannite, grimselite and čejkaite

2020 ◽  
Vol 7 (21) ◽  
pp. 4197-4221 ◽  
Author(s):  
Francisco Colmenero ◽  
Jakub Plášil ◽  
Jiří Sejkora
Keyword(s):  
Mechanical Properties ◽  
Hydrogen Bonding ◽  
Diffraction Pattern ◽  
Crystal Structures ◽  
First Principles ◽  
X Ray Diffraction ◽  
Carbonate Minerals ◽  
X Ray ◽  
Uranyl Carbonate

The structure, hydrogen bonding, X-ray diffraction pattern and mechanical properties of six important uranyl carbonate minerals, roubaultite, fontanite, sharpite, widenmannite, grimselite and čejkaite, are determined using first principles methods.

X-ray studies on crystalline complexes involving amino acids and peptides. XL. Conformational variability, recurring and new features of aggregation, and effect of chirality in the malonic acid complexes of DL- and L-arginine

2002 ◽  
Vol 58 (6) ◽  
pp. 1051-1056 ◽  
Author(s):  
N. T. Saraswathi ◽  
M. Vijayan
Keyword(s):  
Amino Acids ◽  
Hydrogen Bonding ◽  
Amino Acid ◽  
Crystal Structures ◽  
Malonic Acid ◽  
Conformational Flexibility ◽  
X Ray ◽  
Conformational Variability ◽  
Aggregation Pattern ◽  
Positively Charged

The crystal structures of the complexes of malonic acid with DL- and L-arginine, which contain positively charged argininium ions and negatively charged semimalonate ions, further demonstrate the conformational flexibility of amino acids. A larger proportion of folded conformations than would be expected on the basis of steric consideration appears to occur in arginine, presumably because of the requirements of hydrogen bonding. The aggregation pattern in the DL-arginine complex bears varying degrees of resemblance to patterns observed in other similar structures. An antiparallel hydrogen-bonded dimeric arrangement of arginine, and to a lesser extent lysine, is a recurring motif. Similarities also exist among the structures in the interactions with this motif and its assembly into larger features of aggregation. However, the aggregation pattern observed in the L-arginine complex differs from any observed so far, which demonstrates that all the general patterns of amino-acid aggregation have not yet been elucidated. The two complexes represent cases where the reversal of the chirality of half the amino-acid molecules leads to a fundamentally different aggregation pattern.

scholarly journals Structures of (S)-(−)-4-oxo-2-azetidinecarboxylic acid and 3-azetidinecarboxylic acid from powder synchrotron diffraction data

2006 ◽  
Vol 62 (4) ◽  
pp. 606-611 ◽  
Author(s):  
Asiloé J. Mora ◽  
Michela Brunelli ◽  
Andrew N. Fitch ◽  
Jonathan Wright ◽  
Maria E. Báez ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Diffraction Data ◽  
Direct Methods ◽  
X Ray Diffraction ◽  
Synchrotron Diffraction ◽  
X Ray ◽  
The Asymmetry

The crystal structures of the four-membered heterocycles (S)-(−)-4-oxo-2-azetidinecarboxylic acid (I) and 3-azetidinecarboxylic acid (II) were solved by direct methods using powder synchrotron X-ray diffraction data. The asymmetry of the oxoazetidine and azetidine rings is discussed, along with the hydrogen bonding.

Tautomerism and hydrogen bonding in guaninium phosphite and guaninium phosphate salts

2007 ◽  
Vol 63 (3) ◽  
pp. 448-458 ◽  
Author(s):  
El-Eulmi Bendeif ◽  
Slimane Dahaoui ◽  
Nourredine Benali-Cherif ◽  
Claude Lecomte
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Monoclinic Space Group ◽  
Data Sets ◽  
Hydrogen Bond Network ◽  
Space Group ◽  
X Ray ◽  
Bond Network ◽  
Phosphate Salts

The crystal structures of three similar guaninium salts, guaninium monohydrogenphosphite monohydrate, C5H6N5O+·H2O3P−·H2O, guaninium monohydrogenphosphite dihydrate, C5H6N5O+·H2O3P−·2H2O, and guaninium dihydrogenmonophosphate monohydrate, C5H6N5O+·H2O4P−·H2O, are described and compared. The crystal structures have been determined from accurate single-crystal X-ray data sets collected at 100 (2) K. The two phosphite salts are monoclinic, space group P21/c, with different packing and the monophosphate salt is also monoclinic, space group P21/n. An investigation of the hydrogen-bond network in these guaninium salts reveals the existence of two ketoamine tautomers, the N9H form and an N7H form.

Inhibitors of the geotropic response in plants. The crystal structures of 2-[(Naphthalen-2-yl)carbamoyl]benzoic acid (β-Naptalam), 2-(Phenylcarbamoyl)-benzoic acid and 2-(5-Phenyl-1,3,4-oxadiazol-2-yl)benzoic acid

1983 ◽  
Vol 36 (12) ◽  
pp. 2455 ◽  
Author(s):  
G Smith ◽  
CHL Kennard ◽  
GF Katekar
Keyword(s):  
Hydrogen Bonding ◽  
Carboxylic Acid ◽  
Benzoic Acid ◽  
Crystal Structures ◽  
Carboxylic Acids ◽  
Intermolecular Hydrogen Bonding ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carboxylic Acid Groups ◽  
Phthalamic Acid

The crystal structures of three geotropically active phthalamic acid derivatives have been determined by means of X-ray diffraction and the structural systematics for the series compared. The three acids are conformationally similar and, in contrast to the tendency among carboxylic acids to form hydrogen-bonded dimers, they exist as monomers with intermolecular hydrogen bonding between the carboxylic acid groups and the nitrogen or oxygen of the amide side chains.

The Preparation and Crystal Structures of a Series of Urea Adducts: with Fumaric Acid (2 : 1), with Itaconic Acid (1 : 1) and with Cyanuric Acid (1 : 1)

1997 ◽  
Vol 50 (10) ◽  
pp. 1021 ◽  
Author(s):  
Graham Smith ◽  
Colin H. L. Kennard ◽  
Karl A. Byriel
Keyword(s):  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Itaconic Acid ◽  
Fumaric Acid ◽  
Cyanuric Acid ◽  
X Ray ◽  
X Ray Crystallography ◽  
Donor And Acceptor ◽  
Bonding Systems ◽  
Urea Adducts

The adducts of a series of compounds with urea (ur) have been prepared and their crystal structures determined by X-ray crystallography. These are the adducts with the unsaturated aliphatic acids fumaric acid [(fumaric acid)(ur)2] (1) and itaconic acid [(itaconic acid)(ur)] (2), and with cyanuric acid [(cyanuric acid)(ur)] (3). All structures have extensive hydrogen-bonding systems in which most of the urea donor and acceptor sites are involved.

scholarly journals The molecular and crystal structures of 4-N-(2-acetamido-2-deoxy-β-d-glucopyranosyl)-l-asparagine trihydrate and 4-N-(β-d-glucopyranosyl)-l-asparagine monohydrate. The X-ray analysis of a carbohydrate–peptide linkage

1974 ◽  
Vol 143 (1) ◽  
pp. 197-205 ◽  
Author(s):  
L. T. J. Delbaere
Keyword(s):  
Hydrogen Bonding ◽  
Crystal Structures ◽  
Torsion Angle ◽  
Chair Conformation ◽  
Amide Group ◽  
British Library ◽  
X Ray ◽  
Peptide Linkage ◽  
Lending Library ◽  
The Mean

X-ray analyses have shown that the glucopyranose rings of GlcNAc-Asn [4-N-(2-acetamido-2-deoxy-β-d-glucopyranosyl)-l-asparagine] and Glc-Asn [4-N-(β-d-glucopyranosyl)-l-asparagine] both have the C-1 chair conformation and also that the glucose–asparagine linkage of each molecule is present in the β-anomeric configuration. The dimensions (the estimated standard deviations of the last digit are in parentheses) of the glycosidic bond in GlcNAc-Asn and Glc-Asn are, respectively, C(1)-N(1) 0.1441(6)nm, 0.146(2)nm; angle O(5)-C(1)-N(1) 106.8(3)°, 105.7(8)° angle C(2)-C(1)-N(1) 111.1(4)°, 110.4(9)° angle C(1)-N(1)-C(9) 121.4(4)°, 120.5(9)°. The glycosidic torsion angle C(9)-N(1)-C(1)-C(2) is 141.0° and 157.6° in GlcNAc-Asn and Glc-Asn respectively. Hydrogen-bonding is extensive in these two crystal structures and does affect one torsion angle in particular. Two very different values of χ1(N-Cα-Cβ-Cγ) occur for the asparagine residue of the two different molecules; the values of χ1, −69.0° in GlcNAc-Asn and 61.9° in Glc-Asn, correspond to two different staggered conformations about the Cα-Cβbond as the NH3+group is adjusted to different hydrogen-bonding patterns. The two trans-peptide groups in GlcNAc-Asn show small distortions in planarity whereas that in Glc-Asn is more non-planar. The mean plane through the atoms of the amide group at C(2) in GlcNAc-Asn is approximately perpendicular (69°) to the mean plane through the C(2), C(3), C(5) and O(5) atoms of the glucose ring and that at C(1) is less perpendicular (65°). The mean plane through the atoms of the amide group in Glc-Asn makes an angle of only 55° with the mean plane through these same four atoms of the glucose ring. The N(1)-H bond of the amide at C(1) is trans to the C(1)-H bond in these two compounds; the N(2)-H bond of the amide at C(2) is trans to the C(2)-H bond in GlcNAc-Asn. The values of the observed and final calculated structure amplitudes have been deposited as Supplementary Publication SUP 50035 (26 pages) at the British Library (Lending Division), (formerly the National Lending Library for Science and Technology), Boston Spa, Yorks. LS23 7BQ, U.K., from whom copies may be obtained on the terms given in Biochem. J. (1973) 131, 5.

scholarly journals Two metal–organic frameworks based on Sr2+ and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene linkers

2021 ◽  
Vol 77 (12) ◽  
Author(s):  
Muhammad Usman ◽  
Lydia Ogebule ◽  
Raúl Castañeda ◽  
Evgenii Oskolkov ◽  
Tatiana Timofeeva
Keyword(s):  
Hydrogen Bonding ◽  
Single Crystal ◽  
Crystal Structures ◽  
Structural Control ◽  
Metal Organic Frameworks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Organic ◽  
Solvent Systems ◽  
Semiconductor Properties

Two structurally different metal–organic frameworks based on Sr2+ ions and 1,2,4,5-tetrakis(4-carboxyphenyl)benzene linkers have been synthesized solvothermally in different solvent systems and studied with single-crystal X-ray diffraction technique. These are poly[[μ12-4,4′,4′′,4′′′-(benzene-1,2,4,5-tetrayl)tetrabenzoato](dimethylformamide)distrontium(II)], [Sr2(C34H18O8)(C3H7NO)2] n , and poly[tetraaqua{μ2-4,4′-[4,5-bis(4-carboxyphenyl)benzene-1,2-diyl]dibenzoato}tristrontium(II)], [Sr3(C34H20O8)2(H2O)4]. The differences are noted between the crystal structures and coordination modes of these two MOFs, which are responsible for their semiconductor properties, where structural control over the bandgap is desirable. Hydrogen bonding is present in only one of the compounds, suggesting it has a slightly higher structural stability.

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