ISSN:
1432-0614
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
,
Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
Notizen:
Summary Microorganisms are capable of the asymmetric reduction of various types of ketones. From a limited screening with 103 selected microbial strains two have been chosen which reduce ethyl and isopropyl α,1,3-trioxo-2-isoindolinebutyrate (1a and 1b) stereoselectively. The optically active products ethyl and isopropyl α-hydroxy-1,3-dioxo-2-isoindoline butyrate (2a and 2b) are useful precursors of the cerebral insufficiency improver hydroxy-aniracetam. Up to 3% of substrates 1a or 1b can be added in the reaction medium and converted by Candida parapsilosis. The isolated (R)-enantiomers of the product alcohols 2a and 2b show an enantiomeric excess (ee) of 98%–99%. The process was successfully tested on a 200-1 scale, the transformation rate being 0.83 g/1 per day and the yield of isolated product 72%. With Torulopsis magnoliae (S)-enantiomers of the products 2a and 2b were formed with an ee of 97%–99%.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00173723
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