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

Matthew C Urquhart; Nam V Dao; Francesca Ercole; Ben J Boyd; Thomas P Davis; Michael R Whittaker; John F Quinn

doi:10.1021/acsmacrolett.0c00066

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

ACS Macro Lett. 2020 Apr 21;9(4):553-557. doi: 10.1021/acsmacrolett.0c00066. Epub 2020 Mar 26.

Authors

Matthew C Urquhart¹, Nam V Dao¹, Francesca Ercole¹, Ben J Boyd¹, Thomas P Davis^{1

2}, Michael R Whittaker¹, John F Quinn^{1

3}

Affiliations

¹ ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia.
² Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, Queensland 4072, Australia.
³ Department of Chemical Engineering, Faculty of Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.

PMID: 35648511
DOI: 10.1021/acsmacrolett.0c00066

Abstract

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 (H₂S) upon exposure to cysteine. Herein, we examine the propensity of polymers synthesized using RAFT with a dithioester chain transfer agent to release H₂S via reaction of cysteine with constitutive dithioester end-groups. Homocysteine-triggered release of H₂S from these materials is also observed, with evidence suggesting that the mechanism is analogous to the reaction with cysteine.