C-C Bond-Forming Lyases in Organic Synthesis

Lyase catalyzed C-C bond formation is reviewed and an overview of the latest developments in the field of synthetic applications of enzymatic aldol, acyloin condensation, and cyanohydrin reactions, is presented. New insights on enzymatic mechanism and structure, added to an increasing number of synthetic applications has made possible the development of new catalysts and new reactions. The discovery of novel aldolase activity of promiscuous enzymes, and unexpected relaxed substrate specificity, has broadened the opportunities to perform enzymatic carboligations to solve synthetic problems. New techniques such as DYKAT, tandem aldol-Henry methods, or buffer trapping, have expanded the scope of biocatalytic methods. It is also found that more flexibility for the donor substrate is desirable for both aldolases and hydroxynitrilases. Improvements in the stereoselectivity of some enzymes are needed, in particular for TagA and ThrA.