An Efficient Synthetic Strategy for Construction of Functionalized Pentacyclic Skeleton of ecteinascidin-saframycin Alkaloids

摘要

Two functionalized pentacyclic compounds 12a, 12b were constructed via a highly efficient synthetic route, employing a tricyclic amino aldehyde as the key intermediate. The crucial steps involved coupling of two segments via amide bond, Swern oxidation and intramolecular Pictet-Spengler cyclization.