Asymmetric Total Synthesis of Vindorosine, Vindoline, and Key Vinblastine Analogues
作者:Yoshikazu Sasaki、Daisuke Kato、Dale L. Boger
DOI:10.1021/ja106284s
日期:2010.9.29
introducing essentially all the functionality found in the naturalproducts in a single step. Implementation of the approach for the synthesis of 1 and 2 required the development of a ring expansion reaction to provide a 6-membered ring suitably functionalized for introduction of the Δ(6,7)-double bond found in the corestructure of the naturalproducts. Two unique approaches were developed that defined our
asymmetric total synthesis of (-)-vindoline (1) is detailed based on a tandem intramolecular [4+2]/[3+2] cycloaddition cascade of a 1,3,4-oxadiazole inspired by the natural product structure, in which the tether linking the initiating dienophile and oxadiazole bears a chiral substituent that controls the facial selectivity of the initiating Diels-Alder reaction and sets absolute stereochemistry of the remaining