1: 90 percent / NaOCl / CH2Cl2; H2O / 0.83 h / 0 - 5 °C / further reagent; further solvent 2: 1) 85percent H2SO4; 2) 2N NaOH / Irradiation; multistep reaction: 1) 0 deg C, 40 h, λ = 2500-3000 Angstroem; 2) 0 deg C, pH 7-7.4, then 2 h reflux in 0.24N methanolic NaOH; further N-chloro-L-amino-acids; further activation methods (heat or catalyst) instead of irradiation; stereospecific reaction View Scheme

triethylamine in dichloromethane; acetonitrile T=60°C; 4 h; Heating / reflux; Product distribution / selectivity;

phosphate buffer; Humicola amino esterase Ambient temperature; Title compound not separated from byproducts;

phosphate buffer; Humicola amino esterase Ambient temperature; Title compound not separated from byproducts;

triethylamine in acetonitrile T=60°C; 4 h; Heating / reflux;