Chem. shifts and scalar coupling consts. were extd. by symmetry mapping of multiplets in 2-dimensional NMR spectra. The procedure relies on the fact that, in addn. to symmetry with respect to the centers of the multiplets, substructures embedded within the multiplets are partly sym. The recursive anal. is reliable even in the presence of accidental degeneracies, strong coupling, and broad lines as occur in macromols. With minor modifications, the algorithms can be used both for 2D correlation spectra (COSY) and for multiple-quantum spectra, thus allowing complementary evidence to be obtained when accidental overlaps make anal. difficult in either form of 2D NMR spectroscopy. [on SciFinder (R)]