Synthesis and Structural Characterization of Optical Pure (S)-Benzyl-2-(benzyloxycarbonylamino)-4-oxobutanoate

(S)-Benzyl-2-(benzyloxycarbonylamino)-4-oxobutanoate was synthesized from L-methionine via methylation reaction, hydrolysis, carboxyl and amino protection, pyridinium chorochromate(PCC) oxidation. The structure of the target product was characterized by means of 1H NMR, IR and MS. The optical purity was determined by HPLC and polarimeter method. The overall yield was 30.0%. The purity and ee value of the target compound were 99.3% and 99.5% respectively.