20(S)-25-hydroxy vitamin D compounds

摘要

Vitamin D3 analogs in which the methyl group normally attached to the side chain at carbon 20 has been exchanged with the hydrogen atom to form the 20-epi configuration. The compounds are characterized by a marked intestinal calcium transport activity while exhibiting much higher activity than 1 alpha ,25-dihydroxyvitamin D3 in their ability to mobilize calcium from bone. Because of their preferential calemic activity, these compounds would be useful for the treatment of diseases such as hypoparathyroidism or where bone formation is desired, such as low bone turn over osteoporosis. This disclosure is also directed toward 20-epi-3,5-cyclovitamin D compounds useful as intermediates in a process for preparing 20-epi-vitamin D3 analogs.