N-{[4-((2R,3R)-1-(4-fluorophenyl)-3-{[2-(4-fluorophenyl)-2-oxoethyl]thio}-4-oxoazetidin-2-yl)phenoxy]acetyl}glycyl-D-valine

1-(4-fluorophenyl)-3-(R)-[(4-fluorobenzoyl)methylthio]-4-(R)-{4-[N-(α-(R)-{N-[2-(t-butoxy)-(1S)-(t-butoxycarbonyl)ethyl]carbamoyl}benzyl)carbamoylmethoxy]phenyl}azetidin-2-one

N-({4-[(2R,3R)-1-(4-fluorophenyl)-3-{[(2RS)-2-(4-fluorophenyl)-2-hydroxyethyl]thio}-4-oxoazetidin-2-yl]phenoxy}acetyl)glycyl-D-valine

N-{[4-((2R,3R)-1-(4-fluorophenyl)-3-{[(2RS)-2-(4-fluorophenyl)-2-hydroxyethyl]thio}-4-oxoazetidin-2-yl)phenoxy]acetyl}glycyl-3-methyl-D-valine

N-{[4-((2R,3R)-1-(4-fluorophenyl)-3-{[2-(4-fluorophenyl)-2-oxoethyl]thio}-4-oxoazetidin-2-yl)phenoxy]acetyl}glycyl-L-asparagine