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Kinetic Study on the Reactivity of Azanone (HNO) toward Cyclic C-Nucleophiles.

ABSTRACT: Azanone (HNO) is an elusive electrophilic reactive nitrogen species of growing pharmacological and biological significance. Here, we present a comparative kinetic study of HNO reactivity toward selected cyclic C-nucleophiles under aqueous conditions at pH 7.4. We applied the competition kinetics method, which is based on the use of a fluorescein-derived boronate probe FlBA and two parallel HNO reactions: with the studied scavenger or with O₂ (k = 1.8 × 10⁴ M^-1s^-1). We determined the second-order rate constants of HNO reactions with 13 structurally diverse C-nucleophiles (k = 33-20,000 M^-1s^-1). The results show that the reactivity of HNO toward C-nucleophiles depends strongly on the structure of the scavenger. The data are supported with quantum mechanical calculations. A comprehensive discussion of the HNO reaction with C-nucleophiles is provided.

SUBMITTER: Artelska A

PROVIDER: S-EPMC8657990 | biostudies-literature |

REPOSITORIES: biostudies-literature

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