Biocatalyzed Deracemizations

Nakamura et al. have reported the deracemization of sec-alcohols using one microorganism, a strain of a fungus, Geotrichum candidum IFO 5767, and obtained sec-alcohols in high yield and enantiomeric excess [82]. 

Biocatalytic deracemizations of amino acids and hydroxy acids have also been reported [83]. 

The final example constitutes one of the few deracemizations of carboxylic acids 

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Recently, this strategy was applied to the deracemization of propargylic alcohols that are important synthons for the preparation of biologically active compounds such as mifepristone, efavirenz, or petrosynol [63]. A one-pot two-step process employing whole cells from Candida parapsilosis ATCC 7330 was carried out in aqueous medium using short reaction times of 1—4h (Scheme 4.15). Biocatalyzed transformations afforded excellent enantiomeric excess (up to 99%) and isolated yields were from 60-81%. 

D. Koszelewsld, D. Pressnitz, D. Clay, W. Kroutil, Deracemization of mexiletine biocatalyzed by omega-transaminases, Org. Lett. 11 (21) (2009) 4810-4812. 

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