Atorvastatin Enzymatic Synthesis of -4-Cyano-3-Hydroxybutyrate

Atazanavir enzymatic synthesis of (1S,2/ )-[3-chloro-2-hydroxy-1(phenylmethyl) propyl]-carbamic acid,1,1-dimethylethyl ester. 

Similarly after many rounds of DNA shuffling, with screening in the presence of higher concentrations of product, product inhibition was overcome and the HHDH activity was increased 2500-fold compared to the wild-type enzyme. 

The biocatalytic reaction was carried out to produce ethyl (S)-4-chloro-3-hydroxybutyrate 85 the reaction mixture contained 570 ml of 100 mM triethanolamine, D-glucose (298 g), KRED (854 mg), and GDH (578 mg) at pH 7.0 and 25 °C. Then, Na-NADP (98 mg) was added followed by butyl acetate (370 ml) and substrate 86 (240g). The reaction was completed in 8h to obtain 232.61 g (96%) of 85 with ee of 99.5%. Subsequently for conversion of ethyl (S)-4-chloro-3-hydroxybutyrate 85 to ethyl (R)-4-cyano-3-hydroxybutyrate 84 in a 11 jacketed airtight reactor charged with 400 ml 500 rnM NaCN. HHDH was charged as an aqueous solution (1-05 g) and the reaction mixture was heated to 40 °C at pH 7.3 and 70 g of 85 was added with a syringe over 10 min. Product 84 was recovered 61.6 g (93%) with chemical purity of 99.5% and 99.5% ee after 50h reaction time [115]. 

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