. "1N-(1-carbamoyl-2-hydroxypropyl)-15-[3-amino(imino)methylaminopropyl]-6-(1-amino-2-phenylethylcarboxamido)-9,12-dibenzyl-18-(1-hydroxyethyl)-2,2-dimethyl-7,10,13,16,19-pentaoxo-3,4-dithia-8,11,14,17,20-pentaazacycloicosane-1-carboxamide" . "19" . . . . .