H-1H distances from NOEs Long-range (tertiary structure) Sequential ee心告…古 Medium-range (helices) Challenge is to assign all peaks in NOESY spectra 17 17 1H- 1H distances from NOEs Intra-residue A B C D • • • • Z Sequential Medium-range (helices) Long-range (tertiary structure) Challenge is to assign all peaks in NOESY spectra