Antibody-Catalyzed Asymmetric Intramolecular Michael Addition of Aldehydes and Ketones to Yield the Disfavored Cis-Product

摘要

The world's first commercially available catalytic antibody,38C2(Ab38C2),is perhaps the most promiscuous antibody catalyst generated to date.The antibody was found to efficiently catalyze aldol and retro-aldol reactions of a remarkably broad range of substrates with excellent enantioselectivity through an enamine class I aldolase mechanism.The antibody was raised against the beta-diketone hapten 1,which served as a chemical trap to imprint a unique lysine residue(2)with an epsilon-amino group with a pK_a of 5.8(Scheme 1).