(p-I-Phe(4)) dpdpe 135108-10-0 2,5-Pen-4-(4-I-pen)-enkephalin Enkephalin, D-pen(2), D-pen(5), p-I-phe(4) Enkephalin, pen(2,5)-4'-iodo-phe(4)- Enkephalin, penicillamine(2,5)-4-iodopenicillamine(4)- Iodo-dpdpe