Vitamin D5

The motive to study 1α-hydroxyvitamin D5 as a potential pharmaceutical drug stemmed from the tendency of calcitriol, a natural metabolite produced in the kidney, to cause toxic hypercalcemia in patients when dosed at concentrations needed to interrupt prostate cancer cells' cycle and stimulate apoptosis.

[5][6] And while supplementation with dexamethasone decreases hypercalcemia,[7] bypassing it with an equally effective tumor suppressant would reduce patient cost and stress.

1α-Hydroxyvitamin D5 was first synthesized in 1997 by researchers in the Department of Chemistry at the University of Chicago, under Robert M. Moriarty and Dragos Albinescu.

By 2005, the group had revised its synthesis method for a more streamlined, higher yield-producing route.

It involved the photochemical conversion of precursor 7-dehydrositosteryl acetate to contain a conjugated triene system, a hallmark of this analog, followed by hydroxylation, photoisomerization, and deprotection steps.