Benzosulfones as photochemically activated sulfur dioxide (SO2) donors

Abstract

Sulfur dioxide (SO₂) is a gaseous environmental pollutant which is routinely used in industry as a preservative and antimicrobial. Recent data suggests that SO₂ may have value as a therapeutic agent. However, due to its gaseous nature, localizing SO₂ generation is challenging. Herein, various 1,3-dihydrobenzo[c]thiophene 2,2-dioxides (benzosulfones) were prepared as candidates for photochemically activated sulfur dioxide (SO₂) generation. These compounds were found to be stable in buffer but were photolysed upon irradiation with UV light to generate SO₂. Our data indicates that photolysis of benzosulfones depends on substituents, and that the presence of electron donating groups results in an enhanced yield of SO₂.