Chiral amines pyruvate decarboxylase

The ability of pyruvate decarboxylase from many microbial sources to produce phenylacetylcarbinol has been exploited for many years in the synthesis of ephedrine, a natural adrenergic compound (92). The acyloin is reductively aminated to produce the ethanolamine product, (1R,2S)-ephediine, with two chiral centers. 

Hohne, M., Kuhl, S., Robins, K., and Bornscheuer, U. (2008) Efficient asymmetric synthesis of chiral amines by combining aminotransferase and pyruvate decarboxylase. ChemBioChem, 9, 363-365. 

A drawback of using lactate dehydrogenase as a biocatalyst to remove pyruvate from the reaction equilibrium is the need for the NADH cofactor. Another possibility to eliminate the coproduct is the application of a p5uruvate decarboxylase (Scheme 29.6b). A cofactor is not required, and the resulting products of pyruvate decarboxylation, acetaldehyde, and CO are highly volatile, shifting the equilibrium toward the product [68]. Several pyruvate decarboxylases from yeast and bacteria are commercially available and are active at the same pH value as the transaminase required for the asymmetric synthesis of chiral amines. 

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