Organic shift reagents for the NMR analysis of cyclodextrins

NMR Studies of Cyclodextrins and Cyclodextrin Complexes

“…In such media one can obtain detailed insight into the intramolecular CyD hydrogen-bond network (see section B.2), and often observes better resolved signals for other protons. Another way to reach a higher dispersion of overlapping CyD signals is the admixture ofmostly aromaticsubstrates, , which are known to form intracavity complexes and have strong shielding tensors affecting mostly the H-3 and H-5 signals (see section C).…”

“…Enantioselective recognition by cyclodextrins can be most easily analyzed by observation of distinct signals from nonequivalent nuclei ,− with the advantage that these shift reagents can be applied in aqueous solution. On the other hand, spin system analysis of CyDs can be helped by the use of traditional shift reagents . Often more effective chiral discrimination is observed with substituted, for instance permethylated CyDs, − or with mono-acetylamino-β-CyDs, which is thus also applicable in less polar media.…”

“…On the other hand, spin system analysis of CyDs can be helped by the use of traditional shift reagents. 33 Often more effective chiral discrimination is observed with substituted, for instance permethylated CyDs, [192][193][194][195][196] or with monoacetylamino-β-CyDs, 197 which is thus also applicable in less polar media. Addition of lanthanide ions may enhance the observed nonequivalence.…”

Synthesis and characterization of peptidyl-cyclodextrins dedicated to drug targeting

“…This compound was also selected on the basis of its aromatic character, which induces large variations in chemical shifts of proton NMR lines upon inclusion. 19 First, one-dimensional spectra of 7a in the absence and in the presence of the potential guest were compared. Since the spectra are extremely complex, the inclusion complex was demonstrated through the spatial proximities of protons of the host and guest molecules.…”

New amphiphilic derivatives of cyclodextrins for the purpose of insertion in biological membranes: the “Cup and Ball” molecules

“…In this sense, it can be defined as an "organic shift reagent". 14 First, one-dimensional spectra of 4a in the absence and in the presence of the potential guest will be compared. The results are presented in Fig.…”