Green synthesis of enantiopure quinoxaline alcohols using Daucus carota

Biocatalytic enantioselective synthesis of cenobamate, an antiepileptic drug

A green and efficient process for the synthesis of cenobamate has been accomplished in 70% yield and >99% ee through the bio-reduction of β-ketotetrazole using Daucus carota whole plant cells. The corresponding β-hydroxytetrazole was isolated in 60% yield and >98% ee. This is the first report on the biocatalytic reduction of β-ketotetrazole using plant enzymes derived from D. carota root cells with excellent enantioselectivity.

Plant-Mediated Enantioselective Transformation of Indan-1-one and Indan-1-ol. Part 2

The main purpose of this publication was to obtain the S-enantiomer of indan-1-ol with high enantiomeric excess and satisfactory yield. In our research, we used carrot callus cultures (Daucus carota L.), whereby the enzymatic system reduced indan-1-one and oxidized indan-1-ol. During the reaction of reduction, after five days, we received over 50% conversion, with the enantiomeric excess of the formed S-alcohol above 99%. In turn, during the oxidation of racemic indan-1-ol after 15 days, 36.7% of alcohol with an enantiomeric excess 57.4% S(+) remained in the reaction mixture. In addition, our research confirmed that the reactions of reduction and oxidation are competing reactions during the transformation of indan-1-ol and indan-1-one in carrot callus cultures.

Plant-Mediated Enantioselective Transformation of Indan-1-One and Indan-1-ol

The main purpose of this work was to discover the way to obtain pure enantiomers of indan-1-ol. The subject of the study was the ability of the plant enzyme system to reduce the carbonyl group of indan-1-one, as well as to oxidize the hydroxyl group of racemic indan-1-ol. Locally available fruit and vegetables were selected for stereoselective biotransformation. During the reduction, mainly alcohol of the S-(+)-configuration with a high enantiomeric excess (ee = 99%) was obtained. The opposite enantiomer was obtained in bioreduction with the apple and parsley. Racemic indan-1-ol was oxidized by all catalysts. The best result was obtained for the Jerusalem artichoke: Over 50% conversion was observed after 1 h, and the enantiomeric excess of unreacted R-(–)-indan1-ol was 100%.