Automated structure elucidation — the benefits of a symbiotic relationship between the spectroscopist and the expert system

Characteristic features of a new expert system StrucEluc are described. The system is intended for the structure elucidation of complex organic molecules using a variety of spectroscopic data including 2D NMR. We review here the results of challenging this system with over 100 structure elucidation problems where the 2D NMR peak tables presented in original journal publications provided the input data. This contribution is focused on methods to overcome difficult situations that can arise when contradictions are present in the input data and/or when the structure is underdetermined as a result of insufficient 2D NMR correlations. Methods by which to address these situations are examined. It has been shown that synergy between the spectroscopist and the expert system allows the solution of problems that seemed to be hopeless at the outset of the structure elucidation process.