Synthetic and Theoretical Investigations of Myrmicarin Biosynthesis

摘要

Isolated as the active components of the poison gland secretion from various Myrmicaria ant species found in Africa and characterized by the Francke group over a decade ago, the myrmicarin alkaloids (1-6, Figure 1) provide a truly unique array of synthetic challenges. Indeed, myrmicarins 215A and B (1 and 2) as well as myrmicarin 217 (3) are the first examples of naturally occurring pyrrolo-[2,1,5cd]indolizidines, while the higher-order structures (4-6) constitute some of the most complex alkaloids isolated from any insect to date with formidable stereochemical complexity displayed across up to ten ring systems.