The amide functional group is:
Amides are commonly formed from the reaction of a carboxylic acids with an amine:
This is the reaction that forms peptide bonds between amino acids. These amides can participate in hydrogen bonding as hydrogen bond acceptors and donors, but do not ionize in aqueous solution, wheras their parent acids and amines are almost completely ionized in solution at neutral pH.
An amide linkage is kinetically stable to hydrolysis. Amide linkages in a biochemical context are called peptide linkages. Amide linkages constitute a defining molecular feature of proteins, the secondary structure of which is due in part to the hydrogen bonding abilities of amides.
Amides can be broken down in amide hydrolysis.