Recent Advances in the Automated Structure Elucidation System, CHEMICS. Utilization of Two-Dimensional NMR Spectral Information and Development of Peripheral Functions for Examination of Candidates

A program for applying two-dimensional NMR spectroscopic data from ¹H−¹³C COSY (one-bond C−H correlations)/¹H−¹H COSY (three bond H−H correlations) and 2D-INADEQUATE (one-bond C-C correlations) experiments has been developed and introduced into CHEMICS. The main concepts employed in this study consists of making a more accurate assignment of ¹³C and ¹H chemical shifts to carbons and hydrogens in the sample structure at the data analysis step in CHEMICS followed by the generation of more probable structures as candidates using ¹³C−¹³C and ¹H−¹H coupling information. The detailed algorithm are described. In addition, current configuration of CHEMICS including peripheral functions for examination of candidates by mass and ¹³C-NMR spectral prediction and the brief overview are described.