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Spatiotemporally Controlled Nuclear Translocation of Guests in Living Cells Using Caged Molecular Glues as Photoactivatable Tags
Published on: January 17, 2019
Shuttling Motion in a Host-Guest Complex Triggered by Spiropyran to Merocyanine Reversible Chemical Transformation
Denhy Hernández-Melo1, Ruy Cervantes1, Jorge Tiburcio1
1Departamento de Química, Centro de Investigación y de Estudios Avanzados (Cinvestav) , Ciudad de México 07360, México.
Abstract:
A stimulus-responsive guest-containing spiropyran and viologen unit assembles with a 24-membered crown ether into a stable host-guest complex displaying a partially threaded geometry. Acid addition induces guest transformation to a merocyanine species activating a second recognition site, suitable for the formation of a pseudorotaxane. The simultaneous presence of two recognition sites produces a small-amplitude macrocycle shuttling motion, from the viologen to the merocyanine moiety. Base addition returns the guest to its spiropyran form, and concurrently the translation motion stops.
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