Synthesis and Evaluation of Cyclic Sulfite Diesters as Sulfur Dioxide (SO2) Donors

Although sulfur dioxide (SO2) finds widespread use in the food industry as its hydrated form, sulfite, a number of aspects of SO2 biology remain to be completely understood. Among the tools available for intracellular enhancement of SO2, most suffer from poor cell permeability and a lack of control over SO2 release. We report 1,2-cyclic sulfite diesters as a new class of reliable SO2 donors that dissociate in buffer through a nucleophilic displacement to produce SO2 with tuneable release profiles. We provide data in support of the suitability of these SO2 donors to enhance intracellular levels of SO2 at an efficiency superior to sodium bisulfite, the most commonly used SO2 donor for cellular studies.