TRITIUM LABELING OF NALTRINDOLE, A DELTA-RECEPTOR-SELECTIVE OPIOID ANTAGONIST VIA 1-BROMONALTREXONE

The synthesis of[1,5'-H-3(2)]naltrindole (9) with labels at both the m orphine skeleton and the indole moiety was carried out by catalytic tr itiodehalogenation of 1,5'-dibromonaltrindole (8) resulting in a speci fic activity of 46.1 Ci/mmol (1705 GBq/mmol). The brominated precursor was prepared by the Fischer indole synthesis starting from 1-bromonal trexone (7) and (4-bromophenyl)hydrazine.