Asymmetric Syntheses of Pectenotoxins-4 and -8, Part I: Synthesis of the C1–C19 Subunit

David A. Evans, Hemaka A. Rajapakse, Dirk Stenkamp

Angewandte Chemie International Edition · 2002 · 73 citations · 0 references

Concepts

Abstract

The total syntheses of the marine macrolides pectenotoxins-4 and -8 have been realized. The pectenotoxins are a new class of marine macrolides that exhibit a high level of biological activity. Key fragment couplings include a Felkin-selective Grignard addition reaction (green), a metalated dimethylhydrazone alkylation (red), and a late-stage olefination reaction with a β-alkoxy sulfone (blue). The utility of the N-phenylamide as a carboxy surrogate and the use of the base labile tert-butoxydiphenylsilyl ether is also described.