Synthesis of the Southern FGHI Ring System of Azaspiracid‐1 and Investigation into the Controlling Elements of C28‐ and C36‐Ketalization

Abstract

Heading south: An efficient approach to the FGHI southern ring system of azaspiracid-1 is disclosed. Each of the eight stereogenic centers is generated with excellent diastereoselectivity. In addition, the stereochemical outcome of the ketalization steps could be controlled by careful selection of the conditions. Teoc=2-(trimethylsilyl)ethoxycarbonyl; TMS=trimethylsilyl; TIPS=triisopropylsilyl; Bn=benzyl. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2006/z603353_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.