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Updated: Jul 5, 2026
09:04
A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Total synthesis of ingenol
Keiji Tanino1, Kei Onuki, Kohei Asano
1Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan. ktanino@sci.hokudai.ac.jp
Journal of the American Chemical Society
|February 6, 2003
Summary
Total synthesis of ingenol, a complex diterpene from Euphorbia, was achieved using novel reactions. Key steps included constructing the strained ingenane skeleton and stereoselectively introducing the triol moiety.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
Background:
- Ingenol is a complex diterpene isolated from the genus Euphorbia.
- The ingenane skeleton presents a significant synthetic challenge due to its highly strained nature.
Purpose of the Study:
- To achieve the total synthesis of ingenol.
- To develop and utilize novel key reactions for complex molecule construction.
Main Methods:
- Construction of the ingenane skeleton via intramolecular cyclization of an acetylene dicobalt complex.
- Rearrangement of an epoxy alcohol to form the core structure.
- Stereoselective double dihydroxylation of a diene to introduce the C(3),C(4),C(5)-triol moiety.
Main Results:
- Successful total synthesis of ingenol.
- Demonstration of novel synthetic strategies for constructing strained polycyclic systems.
- Efficient introduction of the characteristic C(3),C(4),C(5)-triol functionality.
Conclusions:
- The total synthesis of ingenol was accomplished.
- Novel key reactions enable the construction of challenging natural product skeletons.
- The developed methodology provides a pathway for accessing ingenol and its analogs.
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