A flexible solution to anion transport: Powerful anionophores based on a cyclohexane scaffold

Transmembrane anion carriers (anionophores) have potential for biological activity, including the treatment of channelopathies such as cystic fibrosis. A new family of anionophores has been synthesized, in which three thiourea groups are mounted on a cyclohexane-based scaffold. Though conceptually related to earlier polycyclic systems, these molecules are simpler and far more accessible. Preorganization is somewhat reduced compared to earlier systems, and anion affinities are correspondingly lower. However, transport activities set new records. This surprising performance suggests a role for controlled flexibility in the design of transmembrane anion carriers. Speedy shuttling: New anionophores were developed which are simpler and far more accessible than conceptually related earlier systems. They are also less preorganized and anion affinities are lower (as expected), but transport activities set new records. This surprising performance suggests a role for controlled flexibility in the design of transmembrane anion carriers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.