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Total synthesis of (+)-cyanthiwigin U
Matthew W B Pfeiffer1, Andrew J Phillips
1Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA.
Journal of the American Chemical Society
|April 14, 2005
Summary
Researchers achieved a concise total synthesis of cyanthiwigin U, a tricyclic terpene, using a novel two-directional tandem metathesis reaction. This efficient method constructs the complex cyclohepta[e]indene core in just 12 steps.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
- Terpenoid Chemistry
Background:
- Cyanthiwigin U is a complex tricyclic terpene with potential biological significance.
- Previous synthetic routes to cyanthiwigin U were lengthy and lacked efficiency.
- Developing concise and high-yielding synthetic strategies is crucial for accessing complex natural products.
Purpose of the Study:
- To achieve a concise total synthesis of cyanthiwigin U.
- To establish a novel synthetic methodology for constructing the cyclohepta[e]indene core.
- To demonstrate the utility of two-directional tandem metathesis in natural product synthesis.
Main Methods:
- A 12-step synthetic sequence was designed and executed.
- A key two-directional tandem metathesis reaction was employed.
- The synthesis started from a readily available bicyclo[2.2.2]octene precursor.
Main Results:
- The total synthesis of cyanthiwigin U was successfully accomplished.
- An overall yield of 17% was achieved.
- The cyclohepta[e]indene core was efficiently constructed via the tandem metathesis.
Conclusions:
- A concise and efficient total synthesis of cyanthiwigin U has been developed.
- The two-directional tandem metathesis reaction is a powerful tool for constructing complex polycyclic systems.
- This synthesis provides a valuable route to cyanthiwigin U and related natural products.
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