A Highly Stereoselective Total Synthesis of (+)-9-epi-Dictyostatin

✍ Scribed by Chiara Zanato; Luca Pignataro; Andrea Ambrosi; Zhongyan Hao; Cesare Gennari

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 192 KB
• Volume: 2010
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.201001018

✦ Synopsis

Abstract

The total synthesis of (+)‐9‐epi‐dictyostatin (1b), a diastereomer of the antimitotic marine‐sponge‐derived macrolide (–)‐dictyostatin (1a), was achieved by creating 11 stereogenic centers and 4 stereogenic double bonds with a high level of stereocontrol. The yield for the 29‐step longest linear sequence from Roche ester was 1.53 %. The final key steps to this unnatural product were the vinylzincate C10–C26 addition to aldehyde C1–C9 (leading surprisingly to a complete stereoselectivity for the 9__R__‐epimer), followed by Yamaguchi macrolactonization and global deprotection.