(4R,5S)-1,5-Dimethyl-4-phenyl-3-((R)-2-pyrrolidin-1-yl-propionyl)-imidazolidin-2-one

(4S,5R)-1-((R)-2-Benzylamino-butyryl)-3,4-dimethyl-5-phenyl-imidazolidin-2-one

(4S,5R)-1-((R)-2-Benzylamino-hexanoyl)-3,4-dimethyl-5-phenyl-imidazolidin-2-one