info:eu-repo/semantics/article
HNO Is Produced by the Reaction of NO with Thiols
Fecha
2017-10Registro en:
Suarez, Sebastian; Muñoz, Martina; Álvarez, Lucía; Venâncio, Mateus F.; Rocha, Willian R.; et al.; HNO Is Produced by the Reaction of NO with Thiols; American Chemical Society; Journal of the American Chemical Society; 139; 41; 10-2017; 14483-14487
0002-7863
CONICET Digital
CONICET
Autor
Suarez, Sebastian
Muñoz, Martina
Álvarez, Lucía
Venâncio, Mateus F.
Rocha, Willian R.
Bikiel, Damian Ezequiel
Marti, Marcelo Adrian
Doctorovich, Fabio
Resumen
Azanone (nitroxyl, HNO) is a highly reactive compound whose biological role is still a matter of debate. One possible route for its formation is NO reduction by biological reductants. These reactions have been historically discarded due to the negative redox potential for the NO,H+/HNO couple. However, the NO to HNO conversion mediated by vitamins C, E, and aromatic alcohols has been recently shown to be feasible from a chemical standpoint. Based on these precedents, we decided to study the reaction of NO with thiols as potential sources of HNO. Using two complementary approaches, trapping by a Mn porphyrin and an HNO electrochemical sensor, we found that under anaerobic conditions aliphatic and aromatic thiols (as well as selenols) are able to convert NO to HNO, albeit at different rates. Further mechanistic analysis using ab initio methods shows that the reaction between NO and the thiol produces a free radical adduct RSNOH•, which reacts with a second NO molecule to produce HNO and a nitrosothiol. The nitrosothiol intermediate reacts further with RSH to produce a second molecule of HNO and RSSR, as previously reported.