Lipase-catalyzed enantioselective ring opening of unactivated alicyclic-fused β-lactams in an organic solvent

A highly efficient and very simple method was developed for the synthesis of enantiopure beta-amino acids (e.g. cispentacin) and beta-lactams through the enzyme-catalyzed enantioselective ring opening of unactivated alicyclic, beta-lactams in organic media. High enantioselectivity (E > 200) was observed when the Lipolase flipase B from Candida antarctica)-catalyzed reactions were performed with H2O (1 equiv) in dilsopropyl ether at 60 degreesC. The resolved products, obtained in good chemical yield (36-47%), could be easily separated.