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Water Ligands (water + ligand)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

An efficient use of the WATERGATE W5 sequence for observing a ligand binding with a protein receptor

MAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2008
Kazuo Furihata
Abstract An efficient pulse sequence for observing a ligand binding with a receptor has been developed by incorporating the WATERGATE W5 sequence. In the conventional water ligand observed via gradient spectroscopy (WaterLOGSY) techniques, the water resonance is selectively excited using,e.g. the double-pulsed field gradient spin,echo (DPFGSE) sequence at the initial portion of pulse sequence. In the current version, the modified WATERGATE W5 sequence is incorporated at the initial portion of the pulse sequence, and the resonance at the water frequency can be selectively reserved by the modified WATERGATE W5 sequence. The efficiency of ligand-observed NMR screening techniques has been demonstrated using the human serum albumin (HSA),tryptophan complex. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Hydrogen-bonded three-dimensional network of a lanthanum(III) exocyclic complex with 5,10,15,20-tetra-4-pyridylporphyrin

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009
Sophia Lipstman
In the complex diaquatetranitrato[5-(pyridinium-4-yl)-10,15,20-tri-4-pyridylporphyrin]lanthanum(III) 1,2-dichlorobenzene trisolvate, [La(NO3)4(C40H27N8)(H2O)2]·3C6H4Cl2, the lanthanum ion is coordinated to one of the peripheral pyridyl substituents of the porphyrin entity. Units of the complex are interlinked to one another in three dimensions by a network of O,H...N, O,H...O and N,H...O hydrogen bonds between the water ligands, nitrate ions, and pyridyl and pyridinium groups of adjacent species. This is the first structural report of an exocyclic complex of the tetrapyridylporphyrin ligand with any lanthanide ion and its self-assembly into a three-dimensional architecture sustained by hydrogen bonds. [source]

Square-grid coordination networks of diaquabis(4,4,-bipyridyl)copper(II) crosslinked by hydrogen bonds through two monoanions of 1-benzofuran-2,3-dicarboxylic acid and five molecules of water

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009
Rajesh Koner
The title compound, poly[[[diaquacopper(II)]-di-,-4,4,-bipyridyl] bis(3-carboxy-1-benzofuran-2-carboxylate) pentahydrate], {[Cu(C10H8N2)2(H2O)2](C10H5O5)2·5H2O}n, crystallizes in a single-framework architecture. It is composed of two-dimensional square-grid coordination networks of 1:2:2 copper,4,4,-bipyridine,water units, wherein each copper ion coordinates equatorially to four bipyridyl units and axially to two water ligands. The polymeric nets are intercalated by layers of the benzofurandicarboxylic acid monoanions and additional water species. An extensive array of hydrogen bonds interlinks the various components of the structure. The Cu atom and the bipyridyl entities are located on axes of twofold rotation. This study confirms the preferred monoanionic nature of the benzofurandicarboxylic acid molecule. It reveals a rarely observed extended coordination polymer composed only of copper ions and bipyridyl linkers, and an interesting hydrogen-bonding connectivity between the polymeric layers aided by the benzofurandicarboxylic acid and water components intercalated in the structure. [source]

Micro-Hydration of the MgNO3+ Cation in the Gas Phase

CHEMPHYSCHEM, Issue 11 2007
Barbara Jagoda-Cwiklik Dr.
Abstract Coordination complexes of the magnesium nitrate cation with water [MgNO3(H2O)n]+ up to n=7 are investigated by experiment and theory. The fragmentation patterns of [MgNO3(H2O)n]+ clusters generated via electrospray ionization indicate a considerable change in stability between n=3 and 4. Further, ion,molecule reactions of mass-selected [MgNO3(H2O)n]+ cations with D2O reveal the occurrence of consecutive replacement of water ligands by heavy water, and in this respect the complexes with n=4 and 5 are somewhat more reactive than their smaller homologs with n=1,3 as well as the larger clusters with n=6 and 7. For the latter two ions, the theory suggests the existence of isomers, such as complexes with monodentate nitrato ligands as well as solvent-separated ion pairs with a common solvation shell. The reactions observed and the ion thermochemistry are discussed in the context of ab initio calculations, which also reveal the structures of the various hydrated cation complexes. [source]