83159-95-9 Enkephalin, H-tyr-cyclo-(N(delta)-orn-gly-phe-leu)- Enkephalin, H-tyrosyl-cyclo-(N(delta)-ornithyl-glycyl-phenylalanyl-leucine)- H-Tyr-cyclo-(N(delta)-orn-gly-phe-leu)-enkephalin L-Leucine, L-tyrosyl-D-ornithylglycyl-L-phenylalanyl-, cyclic (5-2)-peptide c-ORN