1α-Hydroxy Derivative of Vitamin D 3 : A Highly Potent Analog of 1α,25-Dihydroxyvitamin D 3

Abstract
The 1α-hydroxy derivative of vitamin D3 has been chemically synthesized and tested for its biological activity. This analog has comparable biological activity on a weight basis to 1,25-dihydroxyvitamin D3 in the stimulation of intestinal calcium transport and bone calcium mobilization in normnal and anephric rats. Because the 1α-hydroxy derivative is synthesized from cholesterol, it is easier and less expensive to prepare than 1α,25-dihydroxy derivative, making it attractive as a drug in the treatment of renal osteodystrophy and hypopara-thyroidism.