Acortatarin A

This chapter is a review of the literature on a small family of natural products named the acortatarins. Our interest in these compounds is largely due to their unique structure, which is a pyrrole-fused morpholine spiroketal. The isolation, structural assignment and later correction, biological activity, and syntheses of these molecules are presented. Although the compounds are not extremely complex, two structures were nevertheless incorrectly assigned (as well as correctly assigned in a less well-cited isolation paper!). With all the modern analytical tools at our disposal, incorrect assignments can and do still occur, and, this is a modern example of how synthetic chemistry was used to identify the errors and make the correct assignments. The progression of our research program toward the development of metal-catalyzed spiroketalization methods and our work on acortatarin A is described.