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Updated: Dec 8, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Unified Total Synthesis of Pentacyclic Stemoamide-type Alkaloids
Yasuki Soda1, Yasukazu Sugiyama1, Makoto Yoritate1
1Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1, Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
Abstract:
The collective synthesis of pentacyclic stemoamide-type alkaloids is recognized as a daunting task despite high demand for a comprehensive biological profiling of these natural products. In this Letter, we report a unified synthesis of seven pentacyclic alkaloids and two unnatural derivatives. The keys to success are (1) the chemoselective assembly of four five-membered building blocks, (2) the direct oxidation of pyrrolidine natural products to pyrrole derivatives, and (3) the stereodivergent construction of totally E- or Z-substituted butenolides.
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