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Updated: Jan 4, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Stereocontrolled Total Synthesis of (+)-Isolaurenidificin and (-)-Bromlaurenidificin
Shoji Kobayashi1, Yutaka Hori1, Ryo Yoneyama1
1Department of Applied Chemistry, Faculty of Engineering , Osaka Institute of Technology , 5-16-1 Ohmiya , Asahi-ku, Osaka 535-8585 , Japan.
Abstract:
We report the first total syntheses of (+)-isolaurenidificin (1) and (-)-bromlaurenidificin (2), the latest acetogenins of the 2,6-dioxabicyclo[3.3.0]octane class. The synthesis features a completely stereoselective one-pot epimerization-ring contraction to establish the cis configuration with respect to C10-H and C12-H of the tetrahydrofuran ring. Six stereogenic centers and an olefin geometry were constructed in a highly stereoselective manner. Absolute configurations of the natural products were deduced by the comparison of NMR data and specific rotations.
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