5-{[16-(1H-indol-3-ylmethyl)-7-(9-amino-6-carboxy-1,4-dioxo-2,5-diazanon-1-yl)-1-(2-aminophenyl)-13-(carbamoylmethyl)-10-(carboxymethyl)-17-ethyl-6-methyl-1,4,9,12,15,18-hexaoxo-5-oxa-8,11,14,17-tetrazaheptacos-3-yl]amino}-4-{[14-amino-15-carboxy-8-(carboxymethyl)-2-(hydroxymethyl)-11-methyl-1,4,7,10,13-pentaoxo-3,6,9,12-tetrazapentadec-1-yl]amino}-3-methyl-5-oxopentanoic acid