For the kinetic studies of BaNTR1 and NfsA towards 1a, a similar biocatalytic setting was used as for the substrate scope screening. The enzyme concentration and reaction time were reduced to 1 µM and 0.4 µM and 45 minutes and 30 minutes for BaNTR1 and NfsA, respectively. In addition, no acetonitrile was added. The concentrations of 1a between 0.5 mM and 25 mM and 2.5 mM to 20 mM were investigated for BaNTR1 and NfsA, respectively. No cofactor regeneration system was used for the kinetic studies of NADH for BaNTR1 and NADPH for NfsA. The concentration of the enzyme was lowered to 0.2 µM and the reaction time was set to 10 min. NADH/NAPH concentrations between 0 and 500 µM and 1 mM 1a were used.