Crixivan Enzymatic Synthesis of Indandiols

The oxidation of 130 by oxygen under pressure was developed af lab scale. Under optimal conditions, the substrate/bisulfite mixture was added to a solution of 130 (3.9 g/1), MAON401 and catalase over 20h. Substrate 130 (65g/l) was converted to sulfonate 133 with a small amount of 131 ( 10%). The enzyme reaction stream was telescoped for cyanation to afford only trans-nitrile 134 in 90% yields from 130. Subsequenfly the nitrile was transformed to the methyl ester and the product was converted to the free base 132. In the final step the free base was crysfallized to afford 135 in 56% yield and 99% ee. The conditions of the procedure were successfully applied to pilot plant scale. Compared with the resolution method in the enzymatic process the product yield was increased by 150%, raw material use was reduced by 59.8%, consumption of water was reduced by 60.7%, and the overall process waste was reduced by 63.1% [167]. 

A metabolic engineering approach [175] and directed evolution techniques [176] were evaluated to avoid side reactions, block degradative pathways, and enhance the desired reaction (conversion of indene to cxs-amino indanol 137 or ds-indanediol). Multiparameter flow cytometry was used to assess indene toxicity, and it was shown that concentrations up to 025 g/1 of indene (0.037g indene per gram dry cell wt.) in batch bioconversions did not influence reaction rate. Using this information, a single-phase 

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