(4R,7S,10S,13R,16S,19R)-10-(4-aminobutyl)-N-[(2S,3R)-1,3-dihydroxybutan-2-yl]-19-[[(2S)-2-[[(2S,3S,4R,5S)-4-[(2S,3S,4R,5S,6S)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2S,3S,4S,5S,6S)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-2-yl]oxy-2,3,5-trihydroxyoxan-2-yl]methylamino]-3-phenylpropanoyl]amino]-7-[(1R)-1-hydroxyethyl]-16-[(4-hydroxy-3-(123I)iodanylphenyl)methyl]-13-(1H-indol-3-ylmethyl)-6,9,12,15,18-pentaoxo-1,2-dithia-5,8,11,14,17-pentazacycloicosane-4-carboxamide