Synthesis of porphyrin-steroid conjugates

Steroids linked to porphyrin fluorophores are being developed to improve the selectivity of photosensitizers for photodyanamic therapy and fluorescence imaging of steroid-hormone positive cancers. A number of porphyrin derivatives substituted with one or two steroid moieties coupled via a 17α-ethynyl group of estradiol, testosterone and 19-nortestosterone were synthesized using Pd(II) as a catalyst.