1-[2-[[2-[[(2-aminophenyl)-oxomethyl]amino]-1-oxoethyl]amino]-3-(4-nitrophenyl)-1-oxopropyl]-2-pyrrolidinecarboxylic acid, o-aminobenzoylglycyl-p-nitro-L-phenylalanyl-L-proline, o-Aminobenzoyl-Gly-p-Nitro-Phe-Pro, 1-(2-{2-[(2-aminophenyl)formamido]acetamido}-3-(4-nitrophenyl)propanoyl)pyrrolidine-2-carboxylic acid, ABZ-GLY-4-NITRO-PHE-PRO-OH, 1-[2-[2-[(2-aminophenyl)carbonylamino]ethanoylamino]-3-(4-nitrophenyl)propanoyl]pyrrolidine-2-carboxylic acid