(2S,2'S)-2,2'-(((2S,2'S)-1,1'-(2,2'-(propane-1,3-diylbis(1H-indole-1,3-diyl))bis(2-oxoacetyl))bis(pyrrolidine-1,2-diyl-2-carbonyl))bis(azanediyl))bis(3-(1H-indol-3-yl)propanoic acid)