(Ser(2)(O-tert-butyl)-leu(5))enkephalyl-thr(6)(O-tert-butyl) 111035-57-5 BUBU L-Threonine, N-(N-(N-(N-(O-(1,1-dimethylethyl)-N-L-tyrosyl-D-seryl)glycyl)-L-phenylalanyl)-L-leucyl)-, 1,1-dimethylethyl ester Leu(5)-enkephalin, ser(2)(O-tert-butyl)-thr(6)(O-tert-butyl) Tyr-ser(O-tert-Bu)-gly-phe-leu-thr(O-tert-Bu) Tyrosyl-seryl(O-t-butyl)-glycyl-phenylalanyl-leucyl-threonine(O-t-butyl)