1: (S)-2-amino-5-(allyloxy)-5-oxopentanoic acid hydrochloride With potassium carbonate in water T=0°C; 0.333333 h; 2: 1-[[(9H-fluoren-9-ylmethoxy)carbonyl]oxy]-2,5-pyrrolidinedione in 1,4-dioxane; water T=20°C; 8 h; Further stages.;

Alcalase-cross-linked-enzyme-aggregates in tert-butyl alcohol T=37°C; pH=7.5; 16 h; aq. phosphate bufferEnzymatic reaction; regioselective reaction;

1: 71 percent / Me3SiCl 2: 84 percent / Na2CO3 / H2O; dioxane / Ambient temperature View Scheme

sodium carbonate 1.) dioxane, 0 deg C, 5 min, 2.) dioxane, 22 deg C, 3 h; Yield given. Multistep reaction;

Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;

Yield given. Multistep reaction. Yields of byproduct given. Title compound not separated from byproducts;