Deasetylaatio

Deasetylaatio, or deacetylation, is the chemical process of removing an acetyl group (CH3CO–) from a molecule. This reaction can occur in chemical synthesis or as a biological transformation, and it often changes the properties and reactivity of the substrate, such as its polarity, solubility, or biological activity.

In chemical contexts, deacetylation typically refers to the hydrolysis of acetyl esters or the removal of acetyl groups from nitrogen atoms in acetylated amides. Common methods involve acidic or basic hydrolysis, sometimes at elevated temperatures, to yield the corresponding deacetylated compound and acetic acid or acetate. Deacetylation is an important step in preparing deprotected intermediates in organic synthesis or in recycling and processing acetylated polymers, such as cellulose acetate, to regenerate non-acetylated materials.

In biology and biochemistry, deacetylation is carried out by enzymes known as deacetylases. The most widely studied are histone deacetylases (HDACs), which remove acetyl groups from lysine residues on histone proteins, influencing chromatin structure and gene expression. There are several classes of HDACs, including metalloenzymes and NAD+-dependent sirtuins, each with distinct substrates and regulatory roles. Deacetylation also occurs on non-histone proteins and affects processes such as metabolism, signaling, and protein stability. In medicine, HDAC inhibitors are explored as therapeutics in cancer and other diseases, illustrating the biological and pharmacological relevance of deacetylation.

Applications of deacetylation span organic synthesis, polymer chemistry, and epigenetics, reflecting its role as a fundamental transformation that alters molecular function.