Bicyclic anionic receptors for carboxylates in water

Area of Science:

• Chemical Biology
• Supramolecular Chemistry

Background:

• Selective recognition of carboxylates in aqueous environments is crucial for biological and medical applications.
• Designing synthetic receptors that mimic natural antibiotics like vancomycin for bacterial cell wall synthesis is a key challenge.

Purpose of the Study:

• To develop a general synthetic approach for creating novel carboxylate receptors.
• To achieve water solubility and explore binding capabilities in aqueous media.

Main Methods:

• Elaboration of a diamino bridge unit into a bicyclic system with a tetralactam anion binding site.
• Introduction of dendrimeric nonacarboxylate units via copper(I)-catalyzed azide-alkyne cycloaddition for water solubility.

Main Results:

• Successfully synthesized three novel carboxylate receptor variants.
• Demonstrated binding of simple carboxylates and polar inorganic anions in water at near-neutral pH.
• Achieved association constants (K_a) up to approximately 400 M⁻¹.

Conclusions:

• The developed versatile synthesis allows access to a range of carboxylate receptor variants.
• These receptors show potential for medical applications, particularly in antibiotic design.
• Further modifications could enhance selectivity and therapeutic utility.