L-Arginine, L-alanyl-L-arginyl-L-seryl-L-leucyl-L-isoleucyl-3-(2-naphthalenyl)-L-alanyl-L- arginyl-(3S)-1,2,3,4-tetrahydro-3-isoquinolinecarbonyl-L-alanyl-L-arginyl- L-arginyl-3-(2-naphthalenyl)-L-