N-Acylamino Acid Amidothiourea: A Versatile Chiral Helical Building Block

Area of Science:

• Supramolecular Chemistry
• Organic Chemistry
• Materials Science

Background:

• Thioureas are vital molecular frameworks with significant hydrogen-bonding capabilities, enabling applications in anion recognition, catalysis, and therapeutics.
• Traditional thiourea anion receptor design often relies on electron-withdrawing groups, which can lead to stability issues with basic anions.

Purpose of the Study:

• To develop advanced N-acylamino acid amidothiourea platforms for enhanced supramolecular functionality.
• To explore the relationship between N-acylamino acid amidothiourea conformation, folding, and material properties.
• To investigate novel strategies for anion recognition, chirality transfer, and macrocyclization synthesis.

Main Methods:

• Design and synthesis of N-amidothioureas incorporating electron-donating amide groups to enhance anion binding affinity via intramolecular charge transfer (ICT).
• Exploitation of molecular allostery and N-N bond conformational switching for dynamic regulation of chirality transfer.
• Utilizing the template effect of folded β-turn structures for efficient macrocyclization and construction of macrocycle-based nanopores.

Main Results:

• Achieved orders-of-magnitude enhancement in anion binding affinity using N-amidothioureas through ICT.
• Demonstrated dynamic control over intramolecular chirality transfer via conformational switching.
• Enabled efficient macrocyclization synthesis and construction of transmembrane transport nanopores.
• Reported self-assembly of supramolecular double helices with linear CD-ee dependence through helicity propagation.

Conclusions:

• N-acylamino acid amidothioureas offer a versatile platform for advanced supramolecular functionalities, including anion recognition and chirality transfer.
• The developed chiral helical building blocks are crucial for creating novel thiourea-based materials with applications in spontaneous resolution and transmembrane transport.
• This work significantly advances the field of thiourea chemistry and its application in functional materials.