Prochiral and chiral resolution in 2H NMR spectra: solutes in stretched and compressed gelatin gels.

We demonstrate prochiral and chiral spectral resolution using residual (2)H NMR quadrupolar splittings over a wide range of anisotropic conditions in liquid samples. We use a reversible gel-stretching/compressing device in a conventional high-field NMR spectrometer. We show the stability of gelatin gels as well as their unique ability to switch between multiple stretched and compressed states, thus also changing the sign of residual dipolar couplings in (1)H and (13)C NMR. This flexibility will be important for resolving spectra of mixtures of other chiral compounds and for structure determination of selected peptides.