Direct and Indirect Enzymatic Methods for the Preparation of Enantiopure Cyclic β-Amino Acids and Derivatives from β-Lactams

Direct enzymatic methods for the preparation of enantiopure cyclic β-amino acids (e.g. cispentacin) and β-lactams through the enzyme-catalyzed enantioselective ring opening of β-lactams in water and organic solvents are reviewed. Indirect methods through the lipase-catalyzed asymmetric acylation of N-hydroxymethylated β-lactams or the lipase-catalyzed hydrolysis of the corresponding ester derivatives, followed by ring opening, are also surveyed.