Reaction, Recognition, Relay: Anhydride Hydrolysis Reported by Conformationally Responsive Fluorinated Foldamers in Micelles

Natural membrane receptors are proteins that can report on changes in the concentration of external chemical messengers. Messenger binding to a receptor produces conformational changes that are relayed through the membrane into the cell; this information allows cells to adapt to changes in their environment. Artificial membrane receptors ( R )‐ 1 and ( S )‐ 1 are helical α‐aminoisobutyric acid (Aib) foldamers that replicate key parts of this information relay. Solution‐phase 19 F NMR spectroscopy of zinc(II)‐capped receptor 1 , either in organic solvent or in membrane‐mimetic micelles, showed messenger binding produced an enrichment of either left‐ or right‐handed screw‐sense; the chirality of the bound messenger was relayed to the other receptor terminus. Furthermore, in situ production of a chemical messenger in the external aqueous environment could be detected in real‐time by a racemic mixture of receptor 1 in micelles. The hydrolysis of insoluble anhydrides produced carboxylate in the aqueous phase, which bound to the receptors and gave a distinct 19 F NMR output from inside the hydrophobic region of the micelles.