Photomodulation of Transmembrane Transport and Potential by Stiff-Stilbene Based Bis(thio)ureas
Sander J. Wezenberg, Li‐Jun Chen, Jasper E. Bos, Ben L. Feringa, Ethan N. W. Howe, Xin Wu, Maxime A. Siegler, Philip A. Gale
Abstract
Membrane transport proteins fulfill important regulatory functions in biology with a common trait being their ability to respond to stimuli in the environment. Various small-molecule receptors, capable of mediating transmembrane transport, have been successfully developed. However, to confer stimuli-responsiveness on them poses a fundamental challenge. Here we demonstrate photocontrol of transmembrane transport and electric potential using bis(thio)ureas derived from stiff-stilbene. UV–vis and 1H NMR spectroscopy are used to monitor E–Z photoisomerization of these bis(thio)ureas and 1H NMR titrations reveal stronger binding of chloride to the (Z)-form than to the (E)-form. Additional insight into the binding properties is provided by single crystal X-ray crystallographic analysis and DFT geometry optimization. Importantly, the (Z)-isomers are much more active in transmembrane transport than the respective (E)-isomers as shown through various assays. As a result, both membrane transport and depolarization can be modulated upon irradiation, opening up new prospects toward light-based therapeutics as well as physiological and optopharmacological tools for studying anion transport-associated diseases and to stimulate neuronal activity, respectively.