Determination of spin-spin couplings from ultrahigh resolution 3D NMR spectra obtained by optimized random sampling and multidimensional Fourier transformation.

An example of precise evaluation of backbone scalar J couplings using random sampling of evolution time space in 3D NMR experiments is presented. The recorded spectrum, due to violation of the Nyquist theorem limitation, exhibits ultrahigh resolution in indirect dimensions compared to standard NMR experiment acquired at the same time. The obtained results enable simple and accurate evaluation of scalar and residual dipolar couplings from a single multidimensional NMR experiment.