Azanone (HNO): generation, stabilization and detection

GALLEGO, CECILIA MARIEL; MAZZEO, AGOSTINA; VARGAS, PAOLA; SUÁREZ, SEBASTIÁN; PELLEGRINO, JUAN; DOCTOROVICH, FABIO

Chemical Science

Royal Society of Chemistry

Año: 2021

2041-6520

HNO (nitroxyl, azanone), joined the ?biologically relevant reactive nitrogen species? family in the 2000s.Azanone is impossible to store due to its high reactivity and inherent low stability. Consequently, itschemistry and effects are studied using donor compounds, which release this molecule in solution andin the gas phase upon stimulation. Researchers have also tried to stabilize this elusive species and itsconjugate base by coordination to metal centers using several ligands, like metalloporphyrins and pincerligands. Given HNO´s high reactivity and short lifetime, several different strategies have been proposedfor its detection in chemical and biological systems, such as colorimetric methods, EPR, HPLC, massspectrometry, fluorescent probes, and electrochemical analysis. These approaches are described andcritically compared. Finally, in the last ten years, several advances regarding the possibility ofendogenous HNO generation were made; some of them are also revised in the present work.