5-benzyl 1-tert-butyl N-(4-methylbenzoyl)-L-glutamate

2-[3-(1,3-bis-tert-butoxycarbonylpropyl)ureido]pentanedioic acid 1-tert-butyl ester

(S)-α-tert-butoxycarbonylamino-γ-(2-aminopyrimidin-4-yl)butyric acid α-tert-butyl ester