26,27-dimethylene-1α, 25-dihydroxyvitamin D2 and 26,27-dimethylene-24-epi-1α, 25-dihydroxyvitamin D2 and preparation method thereof

摘要

Vitamin D2 analogs in which a cyclopentane ring is introduced onto the 25-carbon of the side chain of 1 alpha ,25-dihydroxyvitamin D2 and its 24-epimer are described. The compounds are characterized by a marked intestinal calcium transport activity while exhibiting much lower activity than 1 alpha ,25-dihydroxyvitamin D3 in their ability to mobilize calcium from bone. Because of their preferential calcemic activity, these compounds find utility in the treatment of diseases where bone formation is desired, such as osteoporosis.