58822-25-6 CCRIS 6338 EINECS 261-457-1 ENKEPHALIN, LEUCINE L-Leucine, N-(N-(N-(N-L-tyrosylglycyl)glycyl)-L-phenylalanyl)- Leu-enkephalin Leucine enkephalin Leucine-enkephalin N-(N-(N-(N-L-Tyrosylglycyl)glycyl)-L-phenylalanyl)-L-leucine NSC 350588