Chlorination-Enhanced H+/Cl- Co-Transport by Tyramine-Urea Conjugates
Nyaya Prakash Pradhan1, Pradnyesh Kishor Nagrale1, Bhanwar Lal1
1Department of Chemistry, Indian Institute of Science Education and Research Bhopal (IISER Bhopal), Bhopal, Madhya Pradesh, India.
Chemistry, an Asian Journal
|November 19, 2025
Summary
Researchers developed novel tyramine-urea conjugates for efficient proton/chloride (H+/Cl-) co-transport. Chlorinated derivatives showed enhanced activity, enabling chloride-mediated cancer cell death, suggesting therapeutic potential.
Area of Science:
- Synthetic chemistry
- Biophysical chemistry
- Chemical biology
Background:
- Synthetic ionophores are crucial for mimicking cellular ion transport.
- Precise control over ion transport mechanisms is key for modulating cellular processes.
Purpose of the Study:
- To design and synthesize tyramine-urea conjugates for efficient proton/chloride (H+/Cl-) co-transport.
- To investigate the structure-activity relationship influencing ion transport efficiency and lipophilicity.
Main Methods:
- Synthesis of tyramine-urea conjugates (compounds 3-10).
- Single-crystal X-ray analysis to determine anion binding stoichiometry and interactions.
- 1H NMR titrations to assess anion-binding affinity.
- Liposome-based assays to evaluate ion transport activity.
- Cell viability assays to assess anticancer potential.
Main Results:
- Compounds exhibited 1:1 binding stoichiometry with chloride ions via hydrogen bonding.
- Thiourea derivatives showed stronger chloride binding than urea analogues.
- Ortho-chloro substituents enhanced H+/Cl- co-transport activity significantly (EC50 0.4-3.7 µM).
- Compound 9 demonstrated carrier-mediated symport of H+/Cl- across lipid bilayers.
Conclusions:
- Tyramine-urea conjugates can be engineered for efficient H+/Cl- co-transport.
- Lipophilicity and anion-binding affinity are critical tuning parameters.
- Enhanced ion transport activity in chlorinated derivatives suggests potential in anticancer therapeutics via chloride-mediated cell death.
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