Nitrite anion: the key intermediate in alkyl nitrates degradative mechanism.

Alkyl nitrates are metabolized in vitro to yield nitric oxide, and thiol groups have long been considered necessary cofactors. Here, we report evidence that no reaction between thiols and alkyl nitrates takes place in vitro, but stronger reducing agents, such as iron(II) derivatives, are necessary; alkoxy radicals and nitrite anions are the reaction intermediates. The latter, in slightly acidic conditions, can nitrosate thiols to the corresponding S-nitrosothiols, the real NO releasers.