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Updated: Jun 25, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Asymmetric Total Synthesis of (+)-Acaulone B
Sho Fujii1, Jun Hirabayashi1, Akira Katsuyama1,2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
None:
Acaulone B (1) was isolated from Acaulium sp. H-JQSF. The cyclohexenone moiety of 1 was constructed via late-stage chemo-, regio-, and stereoselective Diels-Alder reactions between a diene unit and the C8-C9 double bond of the 14-membered macrodiolide. The regioselectivity of the [4 + 2] cycloaddition was analyzed by DFT calculations, which showed the lowest Gibbs energy of the TS structure and asynchronous cycloaddition. Our investigation demonstrates the effectiveness of late-stage functionalization of macrocycles to synthesize complex natural products.
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