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As a major class of foldamers, aromatic oligoamide foldamers have attracted intense interest. The rigidity of aromatic residues and amide linkages allows the development of foldamers with readily predictable, stable conformations. Aromatic oligoamide foldamers having backbones fully constrained by intramolecular hydrogen bonds have attracted wide attention. Depending on their lengths, such foldamers adopt crescent or helical conformations with highly negative inner cavities. Cyclizing the backbone of the aromatic oligoamides affords the corresponding macrocycles which are characterised by persistent shapes and non-deformable inner cavities. With their defined, inner cavities, such aromatic oligoamide foldamers and macrocycles have served as hosts for cationic and polar guests, and as transmembrane channels for transporting ions and molecules. Recent synthetic progress resulted in the construction of multi-turn hollow helices that offer three-dimensional inner pores with adjustable depth. Reducing the number of backbone-constraining hydrogen bonds leads to oligoamides which, with their partially constrained backbones, undergo either solvent- or guest-dependent folding. One class of such aromatic olgioamide foldamders, which offer multiple backbone amide NH groups as hydrogen-bond donors, are designed to bind anions with adjustable affinities.
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Using Fluorescence to Enable Innovative Functions of Foldamers
Abstract Monodisperse, sequence‐specific oligomers that adopt regular three‐dimensional structures, termed foldamers, have found widespread use as biomimetics, sensors, and novel materials. This review highlights recent examples in which steady state and time‐resolved fluorescence techniques have clarified foldamer structure or enabled the development of foldamers with exciting and sophisticated functions. Applications of foldamers include their development into bioactive compounds, supramolecular hosts or sensors, and materials with useful optical properties. Examples that illustrate the use of natively fluorescent and fluorophore‐modified foldamers are discussed along with studies of fluorophore interactions with varied dyes.
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- Award ID(s):
- 1904991
- PAR ID:
- 10257936
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 61
- Issue:
- 3-4
- ISSN:
- 0021-2148
- Page Range / eLocation ID:
- p. 185-198
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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