Synthesis and biological evaluation of la,25-dihydroxyvitamin D3 analogues with aromatic side chains attached at C-17

摘要

Two new analogues of the steroid hormone la,25-dihydroxyvitamin D3 with aromatic side chains attached at C-17 were designed to investigate their effects on VDR, HL-60 cell differentiation and tumor cell proliferation. These analogues were prepared by the classical photochemical ring opening approach. After the protection of both the la- and 3beta-hydroxyl in la-hydroxydehydroepiandrosterone with TBS groups, followed by bromination with NBS and debromination in the presence of gamma-collidine, the diene intermediate was obtained. Hydrazone formation followed by iodine oxidation gave a vinyl iodide.