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Updated: Aug 5, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Chloride-Selective Transmembrane Channel Formation by Meta-Positioned Halogen Bond Donors
Rashmi Sharma1, Susmita Sarkar2, Sandip Chattopadhayay1
1Chemistry Department, Indian Institute of Science Education and Research Pune, Pune 411008, Maharashtra, India.
JACS Au
|July 30, 2026
Summary
Researchers developed novel dihalobenzamide derivatives for selective anion transport. The diiodo derivative demonstrated superior chloride channel activity, highlighting halogen bonding
Area of Science:
- Supramolecular chemistry
- Chemical biology
- Membrane transport
Background:
- Supramolecular anion channels are crucial for biological and pharmaceutical applications.
- Achieving high specificity and selectivity in anion transport remains a significant challenge.
- Halogen bonding offers a promising interaction for molecular recognition and self-assembly.
Purpose of the Study:
- To design and synthesize 3,5-dihalobenzamide derivatives for selective anion transport.
- To investigate the role of halogen bonding in anion recognition and transmembrane transport.
- To develop a supramolecular anion channel with enhanced selectivity for chloride ions.
Main Methods:
- Synthesis of 3,5-dichloro-, 3,5-dibromo-, and 3,5-diiodobenzamide derivatives.
- Ion transport assays to evaluate channel activity and selectivity.
- Fluorescence and electrophysiological experiments to confirm channel function and mechanism.
- Theoretical calculations to elucidate self-assembly and interaction mechanisms.
Main Results:
- The diiodo derivative (3) showed significantly higher anion transport activity than dichloro (1) and dibromo (2) analogues.
- Compound 3 was confirmed to function as a selective chloride channel.
- An antiport mechanism was identified for the chloride transport mediated by compound 3.
- Intermolecular hydrogen bonding was found to drive the self-assembly of compound 3 into barrel-rosette structures.
Conclusions:
- 3,5-Dihalobenzamide derivatives, particularly the diiodo analogue, can function as selective supramolecular anion channels.
- Halogen bonding plays a critical role in the selective recognition and transport of chloride ions.
- The self-assembly into supramolecular structures is essential for transmembrane channel formation and function.
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