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Updated: Dec 16, 2025

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Total Synthesis of Acaulide and Acaulone A
Jun Hirabayashi1, Fumika Yakushiji1,2, Akira Katsuyama1,2
1Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan.
Abstract:
Acaulide and acaulone A, which contain 14-membered macrodiolides, were isolated from a culture of Acaulium sp. H-JQSF. The antiosteoporosis activity of acaulide is expected to contribute to drug discovery research for an aging society. We herein report the first total synthesis of acaulide, acaulone A, and 10-keto-acaudiol A. Acaulide and acaulone A were synthesized via the late stage Michael addition to the 14-membered macrodiolide, which was inspired by plausible biosynthetic pathways. This approach succeeded in the construction of the acaulide skeleton, which revealed the specific conformation of the 14-membered macrodiolide for late stage functionalization.
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