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Published on: February 4, 2013
Altering the folding patterns of naphthyl trimers
Gregory J Gabriel1, Steven Sorey, Brent L Iverson
1Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|February 24, 2005
Summary
Researchers designed novel foldamers using aromatic interactions. These synthetic oligomers adopt distinct conformations, like pleated or intercalative folds, in water, demonstrating precise control over molecular architecture.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Materials Science
Background:
- Proteins exhibit secondary structures (helices, sheets) dictated by amino acid sequences.
- Nonnatural foldamers are synthetic molecules designed to mimic protein structures and explore noncovalent interactions.
Purpose of the Study:
- To develop a strategy for creating distinct folding topologies in aqueous solutions.
- To utilize inherent recognition properties of aromatic donor/acceptor interactions for foldamer design.
Main Methods:
- Synthesized oligomers composed of electron-rich 1,5-dialkoxynaphthalene (Dan) and electron-deficient 1,4,5,8-naphthalenetetracarboxylic diimide (Ndi) units.
- Investigated folding topologies of Dan-Ndi-Dan and Dan-Dan-Ndi trimers in aqueous solutions.
- Employed UV-vis and NOESY spectroscopy to analyze molecular conformations.
Main Results:
- The Dan-Ndi-Dan trimer adopted a pleated fold in solution.
- The constitutional isomer, Dan-Dan-Ndi, adopted an intercalative or turn-type fold.
- Spectroscopic analyses confirmed the distinct conformations adopted by the two isomers.
Conclusions:
- Demonstrated the designability of folding naphthyl oligomers.
- Highlighted the utility of directed aromatic interactions for constructing complex molecular assemblies in water.
- This approach offers precise control over foldamer topology in aqueous environments.
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