L-5-Oxo-1,4-diazabicyclo<4.3.0>nonane
(S)-1-[2-(toluene-4-sulfonylamino)ethyl]pyrrolidine-2-carboxylic acid tert-butyl ester
Cbz-L-Ala-L-Pro-OtBu
N-(Ethoxycarbonyl)-L-prolin-tert-butylester
N-Benzyloxycarbonyl-L-alanyl-O-(2-acetamido-3,4,6-tri-O-acetyl-2-desoxy-α-D-galactopyranosyl)-L-threonyl-L-prolyl-L-prolin-tert-butylester