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A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
The first total synthesis of (+/-)-ingenol
Jeffrey D Winkler1, Meagan B Rouse, Michael F Greaney
1Department of Chemistry, The University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. winkler@sas.upenn.edu
Journal of the American Chemical Society
|August 15, 2002
Summary
Researchers report the first total synthesis of ingenol, a complex natural product. This achievement utilized novel diastereoselective reactions to establish key stereochemical features, overcoming significant synthetic challenges in ingenane chemistry.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
Background:
- Ingenol and its derivatives are complex natural products with significant biological activity.
- The total synthesis of ingenanes presents substantial stereochemical challenges, particularly the intrabridgehead stereochemistry.
Purpose of the Study:
- To achieve the first total synthesis of (+/-)-ingenol.
- To develop and apply novel synthetic strategies for constructing the ingenane core structure.
Main Methods:
- Diastereoselective Michael reaction for C-11 methyl stereochemistry.
- Diastereoselective carbene addition for dimethylcyclopropane incorporation.
- Intramolecular dioxenone photoaddition-fragmentation for C-8/C-10 stereochemistry.
Main Results:
- Successful total synthesis of (+/-)-ingenol.
- Establishment of critical C-8/C-10 trans intrabridgehead stereochemistry.
- Efficient oxidation of seven contiguous carbon centers using the C-6alpha hydroxymethyl group.
Conclusions:
- The developed synthetic route provides a viable pathway to ingenol.
- The synthetic strategies employed offer new tools for constructing complex polycyclic molecules.
- This synthesis represents a significant advancement in ingenane chemistry.
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