2-Hydroxychalcone-?-Cyclodextrin Conjugate with pH-Modulated Photoresponsive Binding Properties

Citation:
Paulino, M, Perez-Juste I, Magdalena Cid M, Da Silva JP, Pereira MMA, Basilio N.  2022.  2-Hydroxychalcone-?-Cyclodextrin Conjugate with pH-Modulated Photoresponsive Binding Properties, 2022 OCT 15 JOURNAL OF ORGANIC CHEMISTRY.

Abstract:

Stimuli-responsive supramolecular receptors are important building blocks for the construction of self-assembled functional materials. We report the design and synthesis of a pH and light-responsive 2-hydroxychalcone-beta-cyclodextrin conjugate (1-Ct) and its characterization by spectroscopic and computational methods. 1-Ct follows the typical reaction network of trans-chalcone-flavylium photoswitches. Upon light irradiation, 1-Ct can be photochemically converted into the cis-chalcone/hemiketal forms (1-Cc/1-B) under neutral pH conditions or to the flavylium cation (1-AH+) at acidic pH values. This stimuli-responsive beta-cyclodextrin host, 1Ct, was found to form stronger intramolecular self-inclusion complexes (Kintra = 14) than 1-AH+ (Kintra = 3) and weaker than 1-Cc/1-B (overall Kintra = 179), allowing control over their stability and binding properties by combinations of pH and light stimuli.

Notes:

n/a