Formula (I) in which: R
1
and R
2
, which may be the same or different, each represents a lower alkyl, alkenyl or alkynyl group; R
3
represents a methyl group having α- or β-configuration; R
4
represents a hydrogen atom or an etherifying or esterifying group; R
5
represents a hydrogen atom, a hydroxyl group or a lower alkoxy group; X represents a group OR
4
, or a group NR
6
R
7
wherein R
6
represents a hydrogen atom, an aliphatic or araliphatic group, or an acyl group comprising an aliphatic, araliphatic or aryl group linked to the nitrogen atom by way of a carbonyl group; and R
7
is a hydrogen atom or a lower alkyl group; Y represents a lower alkylene, alkenylene or alkynylene group optionally substituted by a hydroxyl, etherified hydroxyl or esterified hydroxyl group; exhibit potent effects on modulation of cell growth and differentiation, while having low calcaemic activity.
式 (I) 其中R
1
和 R
2
可以相同或不同,各自代表低级烷基、烯基或炔基; R
3
代表具有 α 或 β 构型的甲基; R
4
代表氢原子或醚化或酯化基团; R
5
代表氢原子、羟基或低级烷氧基; X 代表一个基团 OR
4
或一个基团 NR
6
R
7
其中 R
6
代表氢原子、脂族或脂肪族基团,或由通过羰基与氮原子相连的脂族、脂肪族或芳基组成的酰基;以及 R
7
是氢原子或低级烷基;Y 代表低级亚烷基、亚烯基或亚炔基,可选择被羟基、醚化羟基或酯化羟基取代;对细胞生长和分化的调节具有强效作用,同时具有较低的血
钙活性。