Strategies and methodologies for the construction of spiro-gamma-lactams: an update

Spiro-gamma-lactams (spiropyrrolidin-2-ones) are a class of spirocyclic compounds that are present in a wide range of synthetic bioactive and naturally occurring molecules. The increasing attention to spirocyclic lactams in drug discovery has been accompanied by a growing interest in these compounds from a synthetic point of view, namely as synthetic building blocks in organic chemistry, due to their inherent rigidity and complexity. Herein, an insight into the most relevant advances in the synthesis of the spiro-gamma-lactam scaffold since 2015 is provided, addressing issues such as scope, efficiency, selectivity and mechanistic insights.