(2R,3S)-3-Benzyl-2-[4-(4-methyl-piperazine-1-carbonyl)-phenoxy]-4-oxo-azetidine-1-carboxylic acid ((R)-1-phenyl-ethyl)-amide

(2R,3R)-3-Benzyl-2-[4-(4-methyl-piperazine-1-carbonyl)-phenoxy]-4-oxo-azetidine-1-carboxylic acid ((R)-1-phenyl-ethyl)-amide

(2S,3S)-3-Benzyl-2-[4-(4-methyl-piperazine-1-carbonyl)-phenoxy]-4-oxo-azetidine-1-carboxylic acid ((S)-1-phenyl-ethyl)-amide

(2S,3R)-3-Benzyl-2-[4-(4-methyl-piperazine-1-carbonyl)-phenoxy]-4-oxo-azetidine-1-carboxylic acid ((R)-1-phenyl-ethyl)-amide

4-[(2S,3S)-1-(Benzhydryl-carbamoyl)-3-(2-isopropoxy-benzyl)-4-oxo-azetidin-2-yloxy]-benzoic acid