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Updated: Jul 30, 2025
09:54
Synthesis and Characterization of 1,2-Dithiolane Modified Self-Assembling Peptides
Published on: August 20, 2018
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Halogen Interaction Effects on Chiral Self-Assemblies on Cyclodipeptide Scaffolds Across Hierarchy
Zhuoer Wang1, Aiyou Hao1, Pengyao Xing1
1Key Laboratory of Colloid and Interface Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 11, 2023
Summary
Halogenation influences peptide self-assembly and chirality. This study shows how halogen bonds in cyclodipeptides create diverse structures and tunable luminescence, impacting folding and macroscopic properties.
Area of Science:
- Supramolecular Chemistry
- Peptide Self-Assembly
- Halogen Bonding
Background:
- Understanding how chemical modifications influence peptide folding and self-assembly is crucial for designing novel biomaterials.
- Halogen bonding is an increasingly recognized non-covalent interaction with potential in directing molecular assembly.
Purpose of the Study:
- To investigate the hierarchical effects of halogenation on peptide folding and self-assembly.
- To explore the role of halogen bonding in dictating the supramolecular architectures of cyclodipeptides.
- To examine the impact of halogen substituents on chirality and luminescence properties.
Main Methods:
- Synthesis of single- and double-functionalized cyclodipeptides with varying halogen substituents (Cl, Br, I, F, H).
- Solid-state characterization using X-ray diffraction to determine self-assembled structures.
- Spectroscopic analysis to investigate optical properties, including clusteroluminescence and circularly polarized luminescence.
Main Results:
- Single-functionalized cyclodipeptides consistently formed helical nanotubes via intermolecular X···O bonds.
- Double-functionalized cyclodipeptides exhibited diverse architectures (nanotubes, lamellae, triple helices) dependent on halogen substituents.
- A specific cyclodipeptide (Cyclo-BrBr) showed intramolecular halogen bonding, leading to reversed chirality across multiple structural levels.
- High-yield clusteroluminescence (up to 71%) was observed, with tunable circularly polarized luminescence achieved by modifying halogen substituents.
Conclusions:
- Halogenation profoundly impacts peptide self-assembly and chirality at hierarchical levels.
- The type and position of halogen substituents offer precise control over supramolecular structure and macroscopic properties.
- Cyclodipeptides functionalized with halogens present a promising platform for developing advanced materials with tunable optical properties.
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