TC-99M-LABELED ESTRADIOL DERIVATIVES - SYNTHESIS, ORGAN DISTRIBUTION AND TUMOR AFFINITY

As starting material for the Tc-99m labelling 17-(Ferrocenyl-ethinyl)-estradiol and 16-(Ferrocenyliden)-estron were synthesized. These ferrocene derivatives were heated with Mn-Br(CO)(5) and Tc-99m-pertechentate to yield the labelled corresponding cytectrene steroid compounds. In organ distribution studies with infantile female rats a binding of the Tc-99m labelled steroids to the estradiol receptor in the rat uterus was demonstrated. The binding to MXT-mamma tumors in mice yielded a Tc-99m concentration ratio tumor/muscle of 3 : 1.