(2S)-4-cyanomethylenepyrrolidine-1,2-dicarboxylic acid dibenzyl ester

(2S,4S)-4-(cyanomethyl)-N-(9-(9-phenylfluorenyl))proline tert-butyl ester

(2s,4r)-1,2-二苄氧羰基-4-羟基吡咯烷

L-羟基脯氨酸

反-N-苄氧羰基-4-羟基-L-脯氨酸