The amide group and its preparation methods by acid-amine coupling reactions: an overview

The amide bond is one of the most important structural units in nature, as it is part of the backbone of peptides and natural proteins, as well as some essential amino acids, DNA, RNA, hormones, or vitamins found in the body. Furthermore, this bond is significant in the pharmaceutical industry due to its presence in the structure of numerous APIs contained in drugs. This paper reviews the most important methods collected in the bibliography for the preparation of this moiety.