The first enantioselective total syntheses of the allopumiliotoxin A alkaloids 267A and 339B
作者:Steven W. Goldstein、Larry E. Overman、Michael H. Rabinowitz
DOI:10.1021/jo00030a026
日期:1992.2
Short, highly stereocontrolled, asymmetric total synthesis of the title amphibian alkaloids are described. In the first stage the indolizidine ketone 11 is assembled from L-proline in enantiomerically pure form. This short sequence proceeds in five laboratory operations and involves the novel intermediacy of an "unprotected" 2-acylpyrrolidine intermediate (Scheme VII). The (Z)-alkylidene side chain of the target alkaloids are introduced by stereocontrolled aldol dehydration sequences (Schemes X and XI). These enantioselective total syntheses confirm the structures and absolute configurations of the allopumiliotoxins 267A and 339B.