2D-NMR-Guided Constitutional Analysis of Organic Compounds Employing the Computer Program COCON[#]

Abstract

The computer program COCON is introduced as a tool for the comprehensive structure elucidation of unknown organic compounds. In particular, structural proposals made on the basis of the molecular formula and of 2D‐NMR experiments can be analyzed for the existence of alternative constitutions being in agreement with the same data set. The computational speed grounds on the evaluation of ambiguous long‐range connectivity information during the process of structure generation. The data set experimentally obtained for the marine natural product oroidin (1) was selected, because proton‐poor compounds usually cause uncertainties in NMR‐based structure determinations. The calculation results encourage to move from the experience‐based analysis of NMR chemical shifts or of MS fragmentations to the automated evaluation of routinely available connectivity information.

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