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Highly efficient H₂S scavengers via thiolysis of positively-charged NBD amines.

ABSTRACT: H₂S is a well-known toxic gas and also a gaseous signaling molecule involved in many biological processes. Advanced chemical tools that can regulate H₂S levels in vivo are useful for understanding H₂S biology as well as its potential therapeutic effects. To this end, we have developed a series of 7-nitro-1,2,3-benzoxadiazole (NBD) amines as potential H₂S scavengers. The kinetic studies of thiolysis reactions revealed that incorporation of positively-charged groups onto the NBD amines greatly increased the rate of the H₂S-specific thiolysis reaction. We demonstrate that these reactions proceed effectively, with second order rate constants (k ₂) of >116 M^-1 s^-1 at 37 °C for NBD-S8. Additionally, we demonstrate that NBD-S8 can effectively scavenge enzymatically-produced and endogenous H₂S in live cells. Furthering the biological significance, we demonstrate NBD-S8 mediates scavenging of H₂S in mice.

SUBMITTER: Ismail I

PROVIDER: S-EPMC8163142 | biostudies-literature |

REPOSITORIES: biostudies-literature

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