Photorelease of Hydrogen Sulfide (H2S) from Stable Water-Soluble Precursors.

Two hydrogen sulfide photoreleasing molecules (photo-HSRMs), 3-hydroxy-2-naphthalene-methanethiol and the corresponding disulfide, have been synthesized, and their properties and photochemical reactivity have been explored. Both compounds are stable in the neat form and in aqueous solutions in the dark but release H2S under exposure to UVA and UVB light in good quantum and chemical yields. In the presence of thiols, such as cysteine, glutathione, and mercaptoethanol, the yield of hydrogen sulfide release reaches 90%. The mechanism of H2S photorelease from these photo-HSRMs is discussed.