N(1)-(2',6'-dimethyltyrosyl-arginyl-phenylalanyl-lysyl)-N(2)-(tyrosyl-1,2,3,4-tetrahydro-3-isoquinolinecarbonyl-psi(CH2NH)-cyclohexylalanyl-phenylalanyl)ethylenediamine
n(1)-(2',6'-dimethyltyrosyl-arginyl-phenylalanyl-lysyl)-n(2)-(tyrosyl-1,2,3,4-tetrahydro-3-isoquinolinecarbonyl-psi(ch2nh)-cyclohexylalanyl-phenylalanyl)ethylenediamine