An object of the present invention is to synthesize a novel vitamin D
3
derivative having a substituent at the 2α-position.
The present invention provides vitamin D derivatives represented by-Formula (I):
wherein
R
1
represents a saturated aliphatic C
1-15
hydrocarbon group optionally substituted with 1 to 3 hydroxy or protected hydroxy groups; and
R
2
represents a saturated aliphatic C
1-10
hydrocarbon group optionally substituted with one or more substituents, which may be the same or different and which are selected from the group consisting of a hydroxy group, a halogen atom, a cyano group, a lower alkoxy group, an amino group and an acylamino group, provided that when R
2
represents a saturated aliphatic C
1
hydrocarbon group, R
2
is substituted with at least one substituent.