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Abstract Hydrogen sulfide (H2S) is a biologically active molecule that exhibits protective effects in a variety of physiological and pathological processes. Although several H2S‐related biological effects have been discovered by using H2S donors, knowing how much H2S has been released from donors under different conditions remains challenging. Now, a series of γ‐ketothiocarbamate (γ‐KetoTCM) compounds that provide the first examples of colorimetric H2S donors and enable direct quantification of H2S release, were reported. These compounds are activated through a pH‐dependent deprotonation/β‐elimination sequence to release carbonyl sulfide (COS), which is quickly converted into H2S by carbonic anhydrase. Thep‐nitroaniline released upon donor activation provides an optical readout that correlates directly to COS/H2S release, thus enabling colorimetric measurement of H2S donation.
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Intramolecular Thiol‐ and Selenol‐Assisted Delivery of Hydrogen Sulfide
Abstract Arylthioamides have been frequently employed to assess the chemical biology and pharmacology of hydrogen sulfide (H2S). From this class of donors, however, extremely low H2S releasing efficiencies have been reported and proper mechanistic studies have been omitted. Consequently, millimolar concentrations of arylthioamides are required to liberate just trace amounts of H2S, and via an unidentified mechanistic pathway, which obfuscates the interpretation of any biological activity that stems from their use. Herein, we report that H2S release from this valuable class of donors can be markedly enhanced through intramolecular nucleophilic assistance. Specifically, we demonstrate that both disulfide‐ and diselenide‐linked thioamides are responsive to biologically relevant concentrations of glutathione and release two molar equivalents of H2S via an intramolecular cyclization that significantly augments their rate and efficiency of sulfide delivery in both buffer and live human cells.
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- Award ID(s):
- 2143826
- PAR ID:
- 10378124
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 45
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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