Concise Synthesis of Astellatol Core Skeleton

Area of Science:

• Organic Chemistry
• Natural Product Synthesis

Background:

• Sesterterpenoids are a class of natural products with complex structures.
• Astellatol is a challenging sesterterpenoid target due to its intricate polycyclic framework.

Purpose of the Study:

• To develop a novel and efficient synthetic route to the core skeleton of sesterterpenoid astellatol.
• To demonstrate the feasibility of key chemical transformations for constructing complex polycyclic systems.

Main Methods:

• A ten-step enantiospecific synthesis was designed and executed.
• Key steps involved a convergent construction of the tricyclic motif.
• A samarium(II) iodide (SmI2)-induced reductive radical cyclization was employed to form the cyclobutane ring.

Main Results:

• The complete core skeleton of sesterterpenoid astellatol was successfully synthesized.
• The strategy provided facile access to the tricyclic core.
• The pivotal cyclobutane ring was efficiently formed via radical cyclization.

Conclusions:

• A practical and efficient ten-step enantiospecific synthesis of the astellatol core has been established.
• The developed methodology highlights the utility of SmI2-mediated radical cyclizations in complex molecule synthesis.
• This work provides a foundation for further exploration of sesterterpenoid chemistry.