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Dihydrogen Phosphate Anions (dihydrogen + phosphate_anion)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Pyrazino[2.3- g]quinoxaline-Bridged Indole-Based Building Blocks: Design, Synthesis, Anion-Binding Properties, and Phosphate-Directed Assembly in the Solid State

CHEMISTRY - A EUROPEAN JOURNAL, Issue 15 2010
Ting Wang
Abstract Strategies for exploring anionic templates to direct sophisticated supramolecular assembly have attracted attention. Herein, a series of new anion receptors 1,3 containing two indole-based binding sites bridged by linking spacer pyrazino[2.3- g]quinoxaline (PQ) have been rationally designed and prepared from the precursors 2,3-diindol-3,-yl quinoxaline (DIQ) and 5,6-dihydrodiindolo[3,2- a:2,,3,- c]phenazine (DIPZ). X-ray analyses showed a self-connected network and dimeric packing through hydrogen bonding and ,,, stacking interaction in the solid state in the structures of 1 and 2, respectively. All three receptors exhibited a series of prominent absorption bands from the expanded ,,system. The indole-based expanded receptors were found to strongly and selectively bind F,, AcO,, and H2PO4, among the tested anions (F,, Cl,, Br,, AcO,, H2PO4,, HSO4,, NO3,, and ClO4,), and operated as efficient colorimetric sensors for naked-eye detection of fluoride anions in DMSO. These tailored building blocks captured two anions located at far-spaced binding sites, and adopted noninterfering anion-binding processes to guarantee the anion-binding affinity, topology, and dimensionality. Solid-state studies elucidated that the neutral 1,3 interacted with the tetrahedral dihydrogen phosphate anion in proper proportions and designed topologies, thus leading to the formation of a series of multidimensional networks by self-assembly in the solid state. The observations showed a well-characterized phosphate-directed assembly of multidimensional metal-free coordination polymers in the solid state, in which the formed phosphate aggregates, including dimer encapsulated in an indole-mediated hydrogen-bonded pocket and an infinite chain, behaved as anionic templates to direct the self-assembly. However, no evidence proved the presence of such phosphate-directed infinite coordination polymers in solution. [source]

Dihydrogen phosphate mediated supramolecular frameworks in 2- and 4-chloroanilinium dihydrogen phosphate salts

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2010
P. Balamurugan
The title compounds, 2-chloroanilinium dihydrogen phosphate (2CADHP) and 4-chloroanilinium dihydrogen phosphate (4CADHP), both C6H7NCl+·H2PO4,, form two-dimensional supramolecular organic,inorganic hybrid frameworks. In 2CADHP, the dihydrogen phosphate anions form a double-stranded anionic chain generated parallel to the [010] direction through O,H...O hydrogen bonds, whereas in 4CADHP they form a two-dimensional supramolecular net extending parallel to the crystallographic (001) plane into which the cations are linked through strong N,H...O hydrogen bonds. [source]

Codeine dihydrogen phosphate hemihydrate

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2009
Christoph Langes
The cation of the title structure [systematic name: (5,,6,)-6-hydroxy-7,8-didehydro-4,5-epoxy-3-methoxy-17-methylmorphinanium dihydrogen phosphate hemihydrate], C18H22NO3+·H2PO4,·0.5H2O, has a T-shaped conformation. The dihydrogen phosphate anions are linked by O,H...O hydrogen bonds to give an extended ribbon chain. The codeine cations are linked together by O,H...O hydrogen bonds into a zigzag chain. There are also N,H...O bonds between the two types of hydrogen-bonded units. Addditionally, they are connected to one another via O...H,O,H...O bridging water molecules. The asymmetric unit contains two codeine hydrogen cations, two dihydrogen phosphate anions and one water molecule. This study shows that the water molecules are firmly bound within a complex three-dimensional hydrogen-bonded framework. [source]

The Reaction of Hydrogen Atoms with Methionine Residues: A Model of Reductive Radical Stress Causing Tandem Protein,Lipid Damage

CHEMBIOCHEM, Issue 11 2006
Carla Ferreri Dr.
Abstract The occurrence of tandem damage, due to reductive radical stress involving proteins and lipids, is shown by using a biomimetic model. It is made of unsaturated lipid vesicle suspensions in phosphate buffer in the presence of methionine, either as a single amino acid or as part of a protein such as RNase A, which contains four methionine residues. The radical process starts with the formation of H. atoms by reaction of solvated electrons with dihydrogen phosphate anions, which selectively attack the thioether function of methionine. The modification of methionine to ,-aminobutyric acid is accompanied by the formation of thiyl radicals, which in turn cause the isomerization of the cis fatty acid residues to the trans isomers. The relationship between methionine modification and lipid damage and some details of the reductive radical stress obtained by proteomic analysis of irradiated RNase A are presented. [source]