63307-63-1 D-Met(sup 2)pro(sup 5)-enkephalinamide GYKI 14238 L-Prolinamide, L-tyrosyl-D-methionylglycyl-L-phenylalanyl- L-Tyrosyl-D-methionylglycyl-L-phenylalanyl-L-prolinamide enkephalin, Met(2)-ProNH2(5)-