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Updated: Nov 15, 2025

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Asymmetric Total Synthesis of Asperversin A
1School of Pharmaceutical Sciences, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, Tsinghua University, Beijing 100084, China.
Abstract:
Asperversin A represents the first example of a steroid-sterigmatocystin heterodimer. We report the concise asymmetric total synthesis of this natural product in 11 steps (the longest linear sequence). The polycyclic ring system was constructed by a cascade dialdehyde cyclization and the late stage xanthene formation by a phenol-assisted reductive alkylation and a SNAr reaction. The acetal linkage with ergosterol peroxide was furnished by a glycosylation-inspired approach.
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