Hydrogen Peroxide-Responsive Triggers Based on Borinic Acids: Molecular Insights into the Control of Oxidative
Blaise Gatin-Fraudet1,2, Mathilde Pucher1, Thomas Le Saux3
1Université Paris-Saclay, CNRS Institut de Chimie Moléculaire et des Matériaux d'Orsay, UMR CNRS 8182, 91405, Orsay, France.
Abstract:
Arylborinic acids represent new, efficient, and underexplored hydrogen peroxide-responsive triggers. In contrast to boronic acids, two concomitant oxidative rearrangements are involved in the complete oxidation of these species, which might represent a major limitation for an efficient effector (drug or fluorophore) release. Herein, a comprehensive study of H2 O2 -mediated unsymmetrical arylborinic acid oxidation to investigate the factors that could selectively guide their oxidative rearrangement is described. The o-CF3 substituent was found to be an excellent directing group allowing a complete regioselectivity on borinic acid models. This result was successfully applied to synthesizing new borinic acid-based fluorogenic probes, which exclusively release the fluorescent moiety upon H2 O2 treatment. These compounds maintained their superior kinetic properties compared to boronic acids, thus further enhancing the potential of arylborinic acids as valuable new H2 O2 -sensitive triggers.
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