Manfred Schudok

Asymmetric synthesis of l-thienylalanines

Abstract l -Thienylalanines were prepared via the hydantoin and azlactone routes with the key step consisting of the microbial transamination of 2-hydroxy-3-thienylacrylic with l -aspartic acid as amino donor. The transamination reaction was performed by a genetically engineered E. coli strain on scales up to 100 g of l -3-(2-thienyl)alanine 1a and is also applicable to the preparation of the isomeric amino acid 1b and some ring-substituted derivatives.

Enzyme catalyzed resolution of alcohols using ethoxyvinyl acetate

Abstract 1-Ethoxyvinyl acetate is an efficient irreversible acyl transfer reagent for lipase catalyzed esterification in organic solvents. The use of this reagent avoids reactive byproducts resulting in enzyme deactivation, in particular the formation of acetaldehyde using the widely employed vinyl acetate transesterification reagent.