1.D.246. The Crown Ether Macrocycle K⁺ Channel (CEM_K⁺C) Family Yuan et al. 2024 reported and reviewed the characterization of crown ether macrocycles having multiple –OCH₂CH₂–ether repeating units. Crown ethers exhibit hydrophilic cavities due to the inward-facing O-atoms, with the outward-facing ethyl portions provide a lipophilic shell. The optimal polyether ring size for binding different alkali cations was systematically evaluated revealing a close correlation between ring size (hole) and ionic radius that 15-crown-5, 18-crown-6 and 21-crown-7 selectively favors Na⁺, K⁺, and Cs⁺, respectively. Both the unique amphiphilicity and binding selectivity make crown ethers a good ion-binding and -transporting motif for constructing APCs, and in some cases, selective recognition and transport of specific ions have been achieved.
This family belongs to the Crown Ether Artificial Ion Transporter Superfamily.
References:
Yuan, X., J. Shen, and H. Zeng. (2024). Artificial transmembrane potassium transporters: designs, functions, mechanisms and applications. Chem Commun (Camb) 60: 482-500.