Polymers with Dithiobenzoate End Groups Constitutively Release Hydrogen Sulfide upon Exposure to Cysteine and Homocysteine.

Dithioesters are well-established as efficient reversible addition-fragmentation chain transfer (RAFT) agents. More recently, certain small molecule dithioesters have been reported to release the biological signaling molecule hydrogen sulfide (H 2 S) upon exposure to cysteine. Herein, we examine the propensity of polymers synthesized using RAFT with a dithioester chain transfer agent to release H 2 S via reaction of cysteine with constitutive dithioester end-groups. Homocysteine-triggered release of H 2 S from these materials is also observed, with evidence suggesting that the mechanism is analogous to the reaction with cysteine.