26,27-dimethylene-1,25-dihydroxyvitamin D.sub.2 and 26,27- dimethylene-24-EPI-1,25-dihydroxyvitamin D.sub.2 and methods for preparing same

摘要

Vitamin D.sub.2 analogs in which a cyclopentane ring is introduced onto the 25-carbon of the side chain of 1,25- dihydroxyvitamin D. sub.2 and its 24-epimer. The compounds are characterized by a marked intestinal calcium transport activity while exhibiting much lower activity than 1,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. Because of their preferential calcemic activity, these compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis.