| abstract |
A novel useful vitamin D3 derivative which is reduced in influence on systemic calcium metabolism while retaining excellent vitamin D3 activity. The derivative is a 9,10-secopregnane derivative represented by the following general formula [1]. Also provided is a medicinal composition containing the derivative as an active ingredient. In the general formula [1], Y represents (1) a single bond, (2) alkylene, (3) alkenylene, or (4) phenylene; R1 and R2 are the same or different and each represents (1) hydrogen, (2) alkyl, or (3) cycloalkyl, or R1 and R2 in combination represent cycloalkyl in cooperation with the adjacent carbon atom; R3 represents hydrogen or methyl; and Z represents (1) hydrogen, (2) hydroxy, or (3) -NR11R12. |