NMR spectroscopy is one of the most powerful and versatile analytic tools available to chemists. The discrete Fourier transform (DFT) played a seminal role in the development of modern NMR, including the multidimensional methods that are essential for characterizing complex biomolecules. However, it suffers from well-known limitations: chiefly the difficulty in obtaining high-resolution spectra...

the potential of tobacco waste as a viable source of medicinally important flavonoids like rutin has been investigated. three flavonoids, apigenin, quercetin and rutin, have been isolated from waste tobacco leaves, and their identities have been confirmed by uv-visible, 1h-nmr and 13c-nmr spectroscopy. by using analytical hplc, the amount of rutin present in the tobacco leaves, before and after...

A series of macrocyclic CNC pincer pro-ligands based on bis(imidazolium)lutidine salts with octa-, deca- and dodecamethylene spacers have been prepared and their coordination chemistry investigated. Using a Ag2O based transmetallation strategy, cationic palladium(II) chloride complexes [PdCl{CNC-(CH2)n}][BAr(F)4] (n = 8, 10, 12; Ar(F) = 3,5-C6H3(CF3)2) were prepared and fully characterised in s...

The number of poorly water-soluble drug substances in the pharmaceutical pipeline is increasing, and thereby also the need to design effective drug delivery systems providing high bioavailability. One favourable formulation approach is preparation of solid dispersions, where dispersing a poorly water-soluble drug in a water-soluble polymer matrix improves the dissolution behaviour and the bioav...

Despite the large number of noncoding RNAs and their importance in several biological processes, our understanding of RNA structure and dynamics at atomic resolution is still very limited. Like many other RNAs, the Neurospora Varkud satellite (VS) ribozyme performs its functions through dynamic exchange of multiple conformational states. More specifically, the VS ribozyme recognizes and cleaves...

B. Reduction in Saddle-Type Coil Size 5 C. Solenoidal Coils and Magic Angle Spinning 5 D. Microcoils 6 E. Microfabrication 7 F. Direct Comparisons of Probe Sensitivity 8 V. Microliter-Volume Static NMR Spectroscopy 9 A. Natural Product Extracts 9 B. Analysis of Combinatorial Chemistry Products 10 VI. Nanoliter-Volume Static NMR Spectroscopy 10 VII. NMR Detection of Capillary Separations 12 A. F...

Solution- and solid-state nuclear magnetic resonance (NMR) spectroscopy are highly complementary techniques for studying supra-molecular structure. Here they are employed for investigating the molecular chaperone αB-crystallin, a polydisperse ensemble of between 10 and 40 identical subunits with an average molecular mass of approximately 600 kDa. An IxI motif in the C-terminal region of each of...

Microporous materials, having pores and channels on the same size scale as small to medium molecules, have found many important applications in current technologies, including catalysis, gas separation and drug storage and delivery. Many of their properties and functions are related to their detailed local structure, such as the type and distribution of active sites within the pores, and the sp...

Alzheimer disease is characterized by abnormal protein deposits in the brain, such as extracellular amyloid plaques and intracellular neurofibrillary tangles. The tangles are made of a protein called tau comprising 441 residues in its longest isoform. Tau belongs to the class of natively unfolded proteins, binds to and stabilizes microtubules, and partially folds into an ordered beta-structure ...

0146-6380/$ see front matter 2008 Elsevier Ltd doi:10.1016/j.orggeochem.2008.06.006 * Corresponding author. Tel.: +1 423 439 6917; fa E-mail address: [email protected] (Y.L. Jiang). A new and convenient fluorescence spectroscopic method has been developed for the separation and determination of perylene in fossil wood recovered from a late Miocene to early Pliocene Gray Fossil Site in Tennessee, ...