TYR-PRO-PHE-PHE-NH2
ENDOMORPHIN-2;ENDOMORPHIN-2 (HUMAN, BOVINE);H-TYR-PRO-PHE-PHE-NH2;YPFF-NH2;TYR-PRO-PHE-PHE-NH2;(2S)-1-[(2S)-2-amino-3-(4-hydroxyphenyl)propanoyl]-N-[(1S)-1-[[(1S)-1-carbamoyl-2-phenyl-ethyl]carbamoyl]-2-phenyl-ethyl]pyrrolidine-2-carboxamide