acetyl group (–COCH3)

 

amino group (NH2)

acetyl group (–COCH3)

NAC is a thiol that acts as an acetylated precursor to the amino acid l-cysteine; it can reduce various radicals, by donating one electron, or acts as a nucleophile by donating one or two electrons (Figure 1) [33,34]. Its chemical structure, formed by the sulfhydryl functional group (–SH) plus an acetyl group (–COCH3) linked to the amino group (NH2), is responsible for its metabolic activities related to the direct and indirect antioxidant action and mucolytic action [35].