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Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Quinoline-Directed Folding in Anilide-Quinoline Hybrids: Length-Controlled Three-Dimensional Conformational
Wei Xu1,2, Ayami Takeda1, Naoya Kumagai1,3
1Graduate School of Pharmaceutical Sciences, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
JACS Au
|June 26, 2026
Summary
Aromatic oligoamide foldamers using anilide and quinoline units were synthesized. These molecules form distinct cyclic and acyclic structures with tunable conformations and cavities, offering versatile platforms for advanced materials.
Area of Science:
- Supramolecular Chemistry
- Organic Chemistry
- Materials Science
Background:
- Aromatic oligoamide foldamers are investigated for their unique structural properties.
- Quinoline and anilide units offer potential for designing novel foldamer architectures.
Purpose of the Study:
- To synthesize and characterize quinoline-based aromatic oligoamide foldamers.
- To explore the folding behaviors and conformational diversity of cyclic and acyclic architectures.
- To establish anilide-quinoline hybrids as a versatile platform for functional foldamers.
Main Methods:
- One-pot cyclooligomerization and stepwise assembly for cyclic foldamers.
- Intramolecular amidation for cyclic foldamer synthesis.
- Structural analyses including NMR, H/D-exchange, and NOE for conformational studies.
Main Results:
- Cyclic foldamers (A-(n)-Q-(n)) showed ring-size dependent conformations and symmetry.
- The hexamer A6Q6 exhibited a two-state conformational equilibrium and unique solid-state structures.
- Acyclic foldamers (NH2-A-(n)-Q-(n)-CO2H) adopted stable helical structures with internal cavities.
Conclusions:
- Anilide-quinoline hybrids provide a versatile platform for creating size-programmed macrocycles.
- Stable aromatic helices with confined cavities can be achieved using these foldamers.
- The distinct folding behaviors enable the development of functional foldamer architectures.
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