1-[(2S)-吡咯烷甲基]哌啶

N-[(苄氧基)羰基]甘氨酰-N-2-萘基-L-脯氨酰胺

(S)-5-(N-benzyloxycarbonyl-L-prolyloxy)-1-methylimidazolidine-2,4-dione

5-羟基-1-甲基咪唑啉-2,4-二酮

N-丙基-(2s)-(9ci)-2-吡咯烷羧酰胺