Simplified immunosuppressive and neuroprotective agents based on gracilin A

Area of Science:

• Organic Chemistry
• Medicinal Chemistry
• Drug Discovery

Background:

• Natural products are crucial starting points for exploring biologically relevant chemical space.
• Total synthesis and derivative synthesis are historical methods for understanding structure-activity relationships (SAR).
• Current synthetic strategies may not always prioritize hypotheses about essential structural features for bioactivity.

Purpose of the Study:

• To present a novel approach called 'pharmacophore-directed retrosynthesis' for natural product total synthesis.
• To enable earlier identification of simplified bioactive compounds during synthetic efforts.
• To demonstrate the utility of this approach using the spongiane diterpenoid, gracilin A.

Main Methods:

• Hypothesizing a pharmacophore of a natural product as an early synthetic target.
• Utilizing the hypothesized pharmacophore to direct the retrosynthetic analysis.
• Sequentially increasing the structural complexity from the minimal pharmacophore to build SAR profiles.

Main Results:

• Successfully applied pharmacophore-directed retrosynthesis to the total synthesis of gracilin A.
• Identified simplified gracilin A derivatives with potent neuroprotective activity.
• Identified simplified gracilin A derivatives with potent immunosuppressive activity.

Conclusions:

• Pharmacophore-directed retrosynthesis is an effective strategy for natural product synthesis.
• This approach facilitates the early discovery of simplified bioactive congeners.
• The method aids in developing SAR profiles and optimizing drug candidates.