Further investigations of the type II diels-alder route to the bicyclic core of esperamicin/calichemicin reveal a regiochemical misassignment: Meta vs. para selectivity

Abstract

The chemistry of an IMDA reaction product has been investigated and reveals that the regiochemical outcome of the cycloaddition was incorrectly assigned in the original report. The product of this reaction is a skeletal isomer of the esperamicin/calichemicin bicyclic core structure.