Biocatalysis chemoenzymatic process

One of the inherent advantages of enzymes is the ability to discriminate between stereoisomers, often generating products with ena-tiomeric excesses (i.e., of over 98%). Judicious application of biocatalysis can also reduce the number of chemical steps needed to synthesize certain drugs, leading to hybrid chemoenzymatic processes with lower costs and less waste. The range of enzymes used in the synthesis of chiral intermediates has expanded beyond esterases and acylases and... 

TABLE 27.4 Examples of Small Molecule Pharmaceuticals that are Accessible to Biocatalysis or for which a Chemoenzymatic Processes has been Developed Replacing Chemo- and Metal Catalysis ... 

Several approaches to statin side-chain intermediates have so far been discussed. Whereas these chemoenzymatic approaches provide clear benefits over the chemical processes, they do not harness the tme potential of biocatalysis as the biotransformations have simply been inserted into the existing chemical route. Wong and co-workers have developed a more biosynthetic-hke approach by using a mutant 2-deoxyiibose-5-phosphate aldolase (DERA)... 

Combining whole-cell biocatalysis and radical polymerization, researchers at Imperial Chemical Industries (ICI) published a chemoenzymatic route to high-molecular-weight poly(phenylene) [86], This polymer is used in the fibers and coatings industry. However, since it is practically insoluble, the challenge was to make a soluble polymer precursor that could first be coated or spun, and only then converted to poly(phenylene). The ICI process starts from benzene, which is oxidized by Pseudomonas putida cells to cyclohexa-3,5-diene-l,2-diol (see Figure 5.17). The... 

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