Amide

In organic chemistry, a functional group resulting from the condensation of a carboxylic acid and an amine.

  O                     O
 RCOH   +   HNR'  -->  RCNR'
             H           H  
 acid      amine       amide

Amides can participate in hydrogen bonds as hydrogen bond acceptors, and as hydrogen bond donors, but do not ionize in aqueous solution as do their parent acids and amines.

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.