1alpha,25-dihydroxy-19-nor-vitamin D3

1alpha,25-dihydroxy-19-nor-vitamin D3 is a synthetic analog of the active vitamin D hormone, calcitriol (1,25-dihydroxyvitamin D3), characterized by the removal of the C-19 methylene group from the A-ring. This structural modification results in a compound that maintains high affinity for the vitamin D receptor (VDR) and potent antiproliferative and pro-differentiating effects—notably demonstrated in HL-60 leukemia and MCF-7 breast cancer cells—while exhibiting significantly reduced calcemic activity compared to natural calcitriol. This dissociation of biological effects makes it a significant research compound for developing treatments for hyperproliferative diseases and secondary hyperparathyroidism, as it minimizes the risk of hypercalcemia, a common side effect of natural vitamin D therapies. It was synthesized and studied primarily as a lead compound for a new generation of vitamin D analogs, including the closely related D2 analog, paricalcitol.

Other names

19-nor-1,25-dihydroxyvitamin D319-nor-calcitriol1,25-dihydroxy-19-nor-cholecalciferol1alpha,25-(OH)2-19-nor-D3