From solution NMR

The quantity 2i0t- is the average solvation number of the ion by solvent P and hence the quantity n — 2i0, is the average solvation number of the ion by W. Thus from solute NMR data, the average solvation number of an ion as a function of solvent composition can be obtained. The first attempt to do this was made by Frankel, Stengle, and Langford (18) in 1965. 

A related >/4-norcaradiene tricarbonyliron complex is obtained upon reaction of tricy-clo[4.3.1.0l6]deca-2,4-diene with Fe3(CO)12 in boiling benzene (equation 143). However, the [4.3.1]propellane ring system is not retained in the analogous tricarbonylchromium complex. Instead, as suggested from solution NMR and solid state X-ray analyses, the complex assumes a homoaromatic structure, which is intermediate between a norcaradi-ene and a cycloheptatriene system (equation 144)193,194. It is noteworthy that the Cr(CO)3 group prefers the same conformation as the Fe(CO)3 group in the analogous norcaradiene iron complex. 

The structures were either taken from the Brookhaven Databank, or made available by the authors. All the structures were from solution NMR data excepted lbna, where a crystal structure was used. When more than one model is deposited for the same structure, the model giving the best agreement between calculated and experimental shifts was used. The rms error obtained by averaging the shifts from all deposited structures is always within 0.02 ppm of the rms error obtained by using one structure. 

This paragraph summarizes important details of alkylaluminate bonding and coordination, which emerged from solution NMR and X-ray crystallographic studies. 

Muller and co-workers (02JPC(B)7781) investigated the molecular behavior of perdeuterated 1,3,5-trioxane in a cyclophosphazene inclusion compound by dynamic 2D NMR spectroscopy. The experimental data revealed a relatively complex motional behavior (rotational motion around the C3 axis of the molecule and around the channel long axis) in the phosphazene host channels the ring inversion process was almost uneffected by the host lattice and activation barriers, as reported from solution NMR studies (90JPC8845), were derived. 

In Sections II and III, the crystal structure of rhodopsin is briefly reviewed and compared with the dynamic structure in micellar solutions and membranes as inferred from the biophysical methods mentioned above. A structural model of the cytoplasmic surface derived from solution NMR of peptides has been presented (Ifeagle et al., 1997 Katagadda et al., 2001), but this approach does not provide direct information on... 

Generated from Solution NMR Data Application to Rabbit Neutrophil... 

Tetrahedron Report Number 536. Determination of association constants (K.J from solution NMR data, L. Fielding, Tetrahedron, 2000, 56, 6151. 

Figure 23.17 Binding of the estrogen receptor to DNA, as inferred from solution NMR spectroscopy. 

In the solid state and in solution, six-membered tetrahedral phosphorus compounds generally adopt a chair as the most stable ground-state conformation. However, Bentrude has shown, by nmr analysis, that the barrier to chairs twist interconversion is low in some six-membered systems (Day et al, 1984 Bentrude et al, 1984 Beres et al., 1987 Nelson et al., 1987). The twist/chair activation barrier for 1,3,2-oxazaphosphorinanes is low. Compound [79] exists in the twist conformation in the solid state and solution. Compound [80] adopts a full boat conformation, from solution nmr spectroscopy and crystal-structure analysis. 

Structural diversity can be built into the system by simply mixing a variety of components. When the non-porphyrinic component 51 is also introduced into the mixture at room temperature, a statistical (1 3 3 1) mixture of the double rosette assemblies is formed immediately. In the presence of a tripyridine 49 of suitable dimensions as a template, clean amplification from all the possible combinations resulted in a 1 1 mixture of the two homomeric species, the most stable receptor 50 and the symmetrical non-porphyrinic analogue 52. The structures of the homomeric species was established from solution NMR studies, utilising the inherent symmetry of the final product in comparison to the other possible structures. 

R 466 J. G. Kempf and J. P. Loria, Theory and Applications of Protein Dynamics from Solution NMR , Cell Biochem. Biophys., 2002,37,187 R467 E. Kennett and P. Kuchel, Redox Reactions and Electron Transfer Across the Red Cell Membrane , lUBMB Life, 2003,55, 375 R 468 R. G. Khalifah, Reflections on Edsall s Carbonic Anhydrase Paradoxes of an Ultra Fast Enzyme , Biophys. Chem., 2003,100,159 R 469 A. A. Khrapitchev and P. T. Callaghan, Spatial Dependence of Dispersion , Magn. Reson. Imaging, 2003, 21, 373 R 470 I. V. Khudyakov, N. Arsu, S. Jockusch and N. J. Turro, Magnetic and Spin Effects in the Photoinitiation of Polymerization , Des. Monomers Polym., 2003, 6, 91... 

In a related paper, WATERGATE and DANTE pulse sequences were used under MAS condition to selectively excite or suppress peaks in H solid state spectra. As known from solution NMR studies, signal selection or suppression... 

It is cautioned, however, that the use of such a database from solution NMR is not always appropriate for the interpretation of solid-state NMR data, because of a possible source of errors arising from the chemical shift references for the solid and solution NMR studies. Moreover, further larger dispersions of chemical shifts from the solution NMR of globular proteins cannot always be ignored. Such data, however, are not always free from ambiguities in choosing the appropriate chemical shifts of the random coil, which are essential for data collection in solution NMR. These are simply treated as hidden parameters, and not always as necessary parameters for the interpretation of the solid-state NMR, unless NMR data of the fully hydrated samples are concerned. In fact, the chemical shift data available from such databases are in many instances biased as a reference for solid-state NMR because of choice of reference data for both solid and solution NMR. It is advised therefore to utilize the database from the solid state, if one aims to interpret the chemical shift data from solid-state NMR. " ... 

Membranes and model membranes exhibit liquid crystalline behavior and this has been exploited in a number of studies to obtain valuable information on the structure and dynamics of membrane associated peptides and proteins as well as on the interaction of the peptides with the membranes themselves. NMR spectroscopy of nuclei such as proton, carbon, deuterium, nitrogen and phosphorus has been utilized for such purposes. Structure elucidation of membrane-associated peptides and proteins in oriented bilayers by solid-state NMR spectroscopy has been reviewed. A survey on the use of static uniaxially oriented samples for structural and topological analysis of membrane-associated polypeptides is available. The theoretical background has been dealt with and a number of examples of applications provided. In addition, ongoing developments combining this method with information from solution NMR spectroscopy and molecular modelling as well as exploratory studies using dynamic nuclear polarization solid-state NMR have been presented. The use of N chemical shift anisotropy, dipolar interactions and the deuterium quadrupolar split-... 

In the assignment of the roethine carbon resonances in the E-VOH copolymers we have to take in account both tacticity effects, as in PVOH, and sequence distribution effects. For the calculation of the chemical shifts in the sequence triads of solid E-VOH copolymer, the chemical shift additivity rules for aliphatic alcohols, as calculated by Ovenall [5] from solution NMR measurements, have been used ... 

Fielding, L. (2000) Determination of association constants (Ka) from solution NMR Data. Tetrahedron, 56, 6151-6170. 

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