The constitutional assignment of natural products by NMR spectroscopy
is usually based on 2D NMR experiments like COSY, HSQC, and HMBC. In t
his paper, the resulting connectivity information is used as input for
the new structure generating program COCON which both improves and dr
amatically accelerates the process of constitutional assignment. COCON
allows to quantify the value of connectivity information (2D NMR corr
elation data) for structure elucidation problems. Applying COCON, it i
s systematically evaluated to which degree the NMR experiments COSY, H
-1,C-13-HMBC and 1,1-ADEQUATE constrain the number of constitutions co
mpatible with the data sets of two secondary metabolites from marine s
ponges.