Synthesis of putative metabolites of 1alpha,25-dihydroxy-2beta-(3-hydroxypropoxy)vitamin D(3) (ED-71).

1alpha,25-Dihydroxy-2beta-(3-hydroxypropoxy)vitamin D(3) (ED-71), an analog of active vitamin D(3), 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] is under phase III clinical trials in Japan for the treatment of osteoporosis and bone fracture prevention. Since ED-71 has a substituent at the 2beta-position of the A-ring, it is recognized that the metabolic pathway of ED-71 might be more complicated than 1,25(OH)(2)D(3) because of metabolism at the 2beta-position substituent in addition to the inherent metabolism of the side chain. To clarify the metabolism of hydroxypropoxy substituent of the 2beta-positon and a combination of metabolism between side chain and 2beta-positon, four putative metabolites of ED-71 have been prepared as authentic samples.