Benzosultines as sulfur dioxide (SO2) donors.

In order to understand precise biological roles of sulfur dioxide (SO(2)), reliable SO(2) donors, compounds that produce SO(2) under physiological conditions, are necessary. The design and development of 1-phenyl-benzosultine as an efficient SO(2) donor is reported. This compound undergoes cycloreversion to generate SO(2) upon dissolution in aqueous buffer at 37 °C with a yield of 89% and a half-life of 39 min and shows SO(2)-like biological activity in a DNA cleavage assay.