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Updated: Nov 1, 2025

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Total synthesis and complete configurational assignment of amphirionin-2
Shota Kato1, Daichi Mizukami1, Tomoya Sugai1
1Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University 1-13-27 Kasuga, Bunkyo-ku Tokyo 112-8551 Japan hfuwa.50m@g.chuo-u.ac.jp.
Abstract:
Amphirionin-2 is a linear polyketide metabolite that exhibits potent and selective cytotoxic activity against certain human cancer cell lines. We disclose herein the first total synthesis of amphirionin-2 and determination of its absolute configuration. Our synthesis featured an extensive use of cobalt-catalyzed Mukaiyama-type cyclization of γ-hydroxy olefins for stereoselective formation of all the tetrahydrofuran rings found in the natural product, and a late-stage Stille-type coupling for convergent assembly of the entire carbon backbone. Four candidate diastereomers of amphirionin-2 were synthesized in a unified, convergent manner, and their spectroscopic/chromatographic properties were compared with those of the authentic material. The present study culminated in the reassignment of the C5/C7 relative configuration, assignment of the C12/C18 relative configuration, and determination of the absolute configuration of amphirionin-2.
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