A lactam is a cyclic amide, formally derived from an amino alkanoic acid. The term is a portmanteau of the words lactone + amide.

From left to right, general structures of a β-lactam, a γ-lactam, a δ-lactam, and an ε-lactam. The specific structures are β-propiolactam, γ-butyrolactam, δ-valerolactam, and ε-caprolactam.


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.


Tautomerization to lactimsEdit

A lactim is a cyclic carboximidic acid compound characterized by an endocyclic carbon-nitrogen double bond. They are formed when lactams undergo tautomerization.



See alsoEdit


  1. ^ Spencer Knapp, Frank S. Gibson Organic Syntheses, Coll. Vol. 9, p.516 (1998); Vol. 70, p.101 (1992) Online article
  2. ^ Singh, R.; Vince, R. Chem. Rev. 2012, 112 (8), pp 4642–4686."2-Azabicyclo[2.2.1]hept-5-en-3-one: Chemical Profile of a Versatile Synthetic Building Block and its Impact on the Development of Therapeutics"
  3. ^ Pham, P.-T.; Vince, R. Phosphorus, Sulphur and Silicon 2007, 779-791.

External linksEdit

  •   Media related to Lactams at Wikimedia Commons