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.