Oriented media

Cierpicki, T., Bushweller, J. H. Charged gels as orienting media for measurement of residual dipolar couplings in soluble and integral membrane proteins. J. Am. Chem. Soc. 2004, 126, 16259-16266. 

Verdier, L., Sakhaii, P., Zweekstetter, M., Griesinger, C. Measurement of long range H,C couplings in natural products in orienting media a tool for structure elucidation of natural products. /. Magn. Reson. 2003, 163, 353-359. 

Fig. 8.3 Cartoon illustrating the alignment of the particles of two different orienting media, a Disc particles represent lipid bicelles. b Rods represent viral particles. Bicelles orient with their normal orthogonal to the magnetic field and viruses with their long axis parallel to it. (Reproduced with permission from N. Tjandra, Structure 1999, 7, R205-R211.)...

A different approach to determining the magnitude and direction of the alignment tensor is reported in the work by Zweckstetter and Bax [65]. This method consists of a systematic search of solute orientations that have the highest tendency to clash with the orienting media, and is based on the molecular shape of the solute. It works well, provided that solute alignment is driven only by steric interactions. The method is being modified to also consider electrostatic interactions. 

A number of natural product studies reported in 2003 also utilized cryoprobe technology. Among the studies reported, Griesinger et al 56 addressed the measurement of long-range proton-carbon couplings in natural products in orienting media. 

Prestegard JH, Al-Hashimi HM, Tolman JR (2000) NMR structures of biomolecules using field oriented media and residual dipolar couplings. Quart Rev Biophys 33(4) 371 24... 

It has been shown by Griesinger and co-workers that it is possible to measure long-range H-C dipolar couplings for the water insoluble compounds in orienting media. The measurements have been performed for menthol dissolved in solution of poly-y-benzyl-glutamate in chloroform. The results have been used to check the usefulness of the method for elucidation of the stereochemistry of the studied compound. 

Such a data format allows rather economical machine independent packing and unpacking of BE-matrices and is used for data transfer on sequentially organized, byte oriented media. 

In recent years, the use of weakly orienting media has received significant attention for the study of small molecules. Particularly, due to the availability of several chiral orienting media which impart low orientational order on the aligned molecule, it has become possible to distinguish... 

Chiral orienting media provide a powerful means of enantiomeric discrimination by NMR. An overview of chiral media including liquid crystals that are used to assign the absolute configuration of particular classes of compounds using NMR spectroscopy is available. Orientational properties of one of the well-utilized liquid crystalline chiral orienting system, viz. 

The literature covering this area has been divided into the following subsections i) Reviews, Experimental and Computational Methods and New Orienting Media and ii) Structure, Conformation and Dynamics. 

Reviews, experimental and computational methods and new orienting media... 

Orienting media, new experimental methodologies and computational methods... 

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