Asymmetric synthesis of β-amino acids and α-substituted β-amino acids

This review is intended to give a brief summary of some of the more recent developments in the synthesis of p-amino acids and asubstituted amino acids. The first part is concerned with an overview of the naturally occurring compounds containing p-amino acids. The second part summarises results on the synthesis of natural and unnatural p-amino acids, by routes involving the enzymatic resolution of racemic mixtures, the intermediary preparation of perhydropyrimidin-4-ones and the conjugate addition of ammonia equivalents to a, P-unsaturated esters and imides which are all topics near to the scientific interest of the authors. For a more complete overview of the methods developed to obtain enantiomerically pure p-amino acids, including hydrogenation of 3-aminoacrylates and nucleophilic addition of enolates to imines, see two recent excellent reviews.