Concise total synthesis of (±)-actinophyllic acid

Area of Science:

• Organic Chemistry
• Natural Product Synthesis
• Medicinal Chemistry

Background:

• Indole alkaloids represent a significant class of natural products with diverse biological activities.
• Actinophyllic acid is a complex indole alkaloid whose total synthesis presents a considerable challenge.
• Efficient synthetic routes are crucial for accessing complex natural products for further study.

Purpose of the Study:

• To develop a concise and efficient total synthesis of the complex indole alkaloid (±)-actinophyllic acid.
• To establish a novel synthetic strategy for constructing the tetracyclic core of actinophyllic acid.
• To demonstrate the utility of Lewis acid-catalyzed cascade reactions in natural product synthesis.

Main Methods:

• A 10-step synthetic sequence starting from readily available materials.
• Lewis acid-catalyzed cascade reaction involving stabilized carbocations to form the tetracyclic core.
• Strategic selection of protecting groups for optimal intermediate conversion.

Main Results:

• Successful and concise total synthesis of (±)-actinophyllic acid in 10 steps.
• Efficient construction of the tetracyclic core in a single chemical operation via a cascade reaction.
• Demonstration of a robust protecting group strategy for the final synthetic steps.

Conclusions:

• The developed synthetic route provides an efficient access to (±)-actinophyllic acid.
• The Lewis acid-catalyzed cascade reaction is a powerful tool for constructing complex polycyclic systems.
• This synthesis offers a valuable platform for exploring analogs and biological activities of actinophyllic acid.