Kudos to Codexis and Merck for their 2010 Presidential Green Chemistry Challenge Award! Codexis developed a transaminase to convert a ß-ketoamide into a chiral ß-amino amide, and Codexis and Merck implemented this biocatalytic process to manufacture sitagliptin. The benefits of this step include eliminating one intermediate, improved yields and productivity, decreased waste, and more flexibility in selecting process equipment. [(Savile, C. K.; Janey, J. M., et al., Science, 2010, 329, 305 (16 July)] By superseding the previous manufacturing route with a biocatalytic route clearly it is possible to improve upon even optimized, creative manufacturing processes.
Recent publications by Codexis show it is feasible to select and develop enzymes for productive processing, e.g., operations at 0.5 M or higher in substrate at above ambient temperatures with up to 50% organic solvents and loadings of <1 wt% enzyme. Previously researchers have adapted conditions to best utilize existing enzymes, but now biocatalysts can be developed to meet the demands for desired operations.