Extra hydrogen bonding interactions by peripheral indole groups stabilize benzene-1,3,5-tricarboxamide helical...

Area of Science:

• Supramolecular chemistry
• Polymer science

Background:

• Benzene-1,3,5-tricarboxamide (BTA) monomers are known for self-assembly into ordered structures.
• Tryptophan-derived BTAs offer unique functionalization possibilities due to the indole group.

Purpose of the Study:

• To investigate the self-assembly behavior of BTA monomers derived from tryptophan alkyl esters.
• To understand the role of the indole N-H group in stabilizing helical assemblies.
• To compare the solution viscosity of BTA Trp with other BTA derivatives.

Main Methods:

• Synthesis of BTA monomers from tryptophan alkyl esters.
• Characterization of self-assembled structures using techniques like NMR and microscopy.
• Viscosity measurements of solutions containing BTA Trp and control compounds.

Main Results:

• BTA Trp monomers self-assemble into helical structures.
• A unique hydrogen bond network involving the indole N-H groups was identified, stabilizing the helices.
• BTA Trp solutions exhibited significantly higher viscosity compared to other alkyl and ester BTAs.

Conclusions:

• The indole N-H group plays a crucial role in stabilizing the helical assemblies of BTA Trp.
• Enhanced stability leads to increased solution viscosity, highlighting potential applications in materials science.
• Tryptophan-derived BTAs represent a promising class of self-assembling molecules with tunable properties.