Lactam

A lactam is a cyclic amide. The term is a portmanteau of the words lactone + amide.

Greek prefixes in alphabetical order indicate ring size:

This ring-size nomenclature stems from the fact that a hydrolyzed α-Lactam leads to an α-amino acid and a β-Lactam to a β-amino acid, etc.

General synthetic methods exist for the organic synthesis of lactams.

Lactim is a cyclic carboximidic acid compound characterized by an endocyclic carbon-nitrogen double bond. It is formed when lactam undergoes tautomerization.