N-(tert-butoxycarbonyl)-2-methyl-L-proline
(S)-1-((benzyloxy)carbonyl)-2-methylpyrrolidine-2-carboxylic acid
N-(tertbutyloxycarbonyl)-α-methyl-L-prolyl-L-phenylalanine
N-(tertbutyloxycarbonyl)-α-methyl-L-prolyl-L-phenylalanine methyl ester
benzyl (S)-2-carbamoyl-2-methylpyrrolidine-1-carboxylate