Total synthesis of (+)-sarain A

Area of Science:

• Organic Chemistry
• Natural Product Synthesis
• Medicinal Chemistry

Background:

• Sarain A is a complex marine alkaloid with potential biological activity.
• Previous synthetic efforts have not achieved an enantioselective total synthesis.

Purpose of the Study:

• To develop a novel and efficient enantioselective total synthesis of (+)-sarain A.
• To explore new synthetic methodologies for constructing complex alkaloid structures.

Main Methods:

• Asymmetric Michael addition for stereocenter installation.
• Enoxysilane-N-sulfonyliminium ion cyclization for quaternary carbon stereocenter.
• Ring-closing metathesis and intramolecular Stille coupling for macrocycle formation.

Main Results:

• Successful enantioselective total synthesis of (+)-sarain A.
• Construction of the diazatricycloundecane core.
• Formation of the unsaturated 14-membered macrocycle.

Conclusions:

• The developed synthetic route is efficient and versatile.
• This synthesis provides a platform for further derivatization and biological evaluation of sarain A analogs.