Enantioselective reduction of 4-chromanone and its derivatives by selected filamentous fungi

Biotransformation of 4-chromanone and its derivatives in the cultures of three biocatalysts: Didymosphaeria igniaria, Coryneum betulinum and Chaetomium sp. is presented. The biocatalysts were chosen due to their capability of enantiospecific reduction of low-molecular-weight ketones (acetophenone and its derivatives and α- and β-tetralone). The substrates were reduced to the respective S-alcohols with high enantiomeric excesses, according to the Prelogʹs rule. In the culture of Chaetomium sp. after longer biotransformation time an inversion of configuration of the formed alcohols was also observed. The highest yield of transformation was observed for 6-methyl-4-chromanone. In all the tested cultures, the higher was the molecular weight of a chromanone, the lower conversion percent was observed.