Deprotection of tert-butoxycarbonyl group of (S)-pyrroloindole (I) by treatment with 3 M HCl in EtOAc afforded amine (II). Then, coupling two equivalents of amine (II) with one equivalent of (phenylene)diacrylic acid (III) in the presence of EDC [N-ethyl-N'-(dimethylaminopropyl)carbodiimide] provided the target bisamide.