(S)-1-Benzyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylate;(2S)-4-Oxo-1,2-pyrrolidinedicarboxylic Acid 1-Benzyl 2-Methyl Ester;(2S)-4-Oxo-1,2-pyrro;(2S)-4-oxo-1,2-Pyrrolidinedicarboxylic acid 2-methyl 1-(phenylmethyl) ester;(S)-L-Benzyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxyl;1-O-benzyl 2-O-methyl (2S)-4-oxopyrrolidine-1,2-dicarboxylate;(2S)-N-Benzyloxycarbonyl-4-oxoproline methyl ester;(S)-1-benzyloxycarbonyl-4-oxoproline methy;(S)-L-benzyl-2-methyl 4-oxopyrrolidine-1,2-dicarboxylate;4-oxo-1-<(phenylmethoxy)carbonyl>-L-proline methyl ester;methyl (2S)-1-(benzyloxycarbonyl)-4-oxo-2-pyrrolidinecarboxylate;methyl (2S)-1-benzyloxycarbonyl-4-oxopyrrolidine-2-carboxylate;Methyl (S)-1-CBZ-4-oxo-2-pyrrolidine carboxylate