1-6-beta-Neoendorphin (human), 2-D-alanine- 2-D-Alanine-1-6-beta-neoendorphin (human) 81733-79-1 BRN 4287455 Dalargin Enkephalin-leu, ala(2)-arg(6)- L-Arginine, N(sup 2)-(N-(N-(N-(L-tyrosyl-D-alanyl)glycyl)-L-phenylalanyl)-L-leucyl)- N(sup 2)-(N-(N-(N-(L-Tyrosyl-D-alanyl)glycyl)-L-phenylalanyl)-L-leucyl)-L-arginine Tyrosyl-D-alanyl-glycyl-phenylalanyl-leucyl-arginine