DU8+Computations Reveal a Common Challenge in the Structure Assignment of Natural Products Containing a Carboxylic Anhydride Moiety

DU8+ computations of NMR spectra revealed a relatively common error in the structure assignment of carboxylic anhydride-containing natural products. Computationally driven revisions of ten of these structures are reported in this Note. The majority of the misassigned structures featured a hydroxy group that is proximal to the proposed anhydride moiety and capable of lactone formation.

Automated summary

Computational analysis of NMR spectra revealed a common error in the structure assignment of carboxylic anhydride-containing natural products. This note reports computationally driven revisions of ten such structures, many of which featured a hydroxy group capable of lactone formation near the proposed anhydride moiety.