NOESY and DFT-GIAO Calculations Reveal Pervasive Errors in C20 Configurations of Taraxastane-3,20-diols: Proposals to Improve NMR Structure Determinations

The current scientific consensus generally assigns incorrect C20 configurations to taraxastane-3β,20-diols and their oxo derivatives reported in 32 articles. Definitive configurations established here by NOESY, quantum mechanical NMR predictions, and