N,N-Diethyl-2-(2-oxo-4-phenyl-pyrrolidin-1-yl)-acetamide

(2-oxo-4-phenyl-1-pyrrolidinyl)acetic acid carboethoxymethyl ester

4-[2-(2-oxo-4-phenyl-pyrrolidin-1-yl)-acetylamino]-butyric acid ethyl ester