propionylating

Propionylating is the chemical process of introducing a propionyl group, derived from propionic acid, onto another molecule. The propionyl group is a three-carbon acyl moiety with the structure CH3-CH2-CO-. In practice, propionylation is a form of acylation that transfers this group to nucleophiles such as amines or alcohols, producing amides or esters respectively.

In organic synthesis, propionylation is commonly used to protect functional groups or to prepare propionylated derivatives for further transformations. Reagents such as propionyl chloride and propionic anhydride are typical propionyl donors. Amine substrates can be converted to N-propionyl derivatives by reaction with propionyl chloride or propionic anhydride in the presence of a base; alcohols can form propionate esters under similar conditions. Reactions are typically conducted under anhydrous conditions due to the moisture sensitivity of acylating reagents.

In biochemistry and cell biology, propionylation refers to the post-translational modification where a propionyl group is added to lysine or other sites on proteins, a modification that is more recently recognized alongside acetylation and butyrylation. Propionyl-CoA serves as the biological donor of the propionyl group in cells. Histone and nonhistone propionylation can influence chromatin structure and gene expression, and is regulated by enzymes with depropionylase activity, including certain sirtuins. The study of propionylation contributes to understanding the broader landscape of protein acylation and its regulatory roles.

Overall, propionylating encompasses both synthetic and biological contexts, highlighting its use in materials chemistry and in the regulation of protein function.