Compounds of formula I are provided where X
1
and X
2
are independently selected from H or hydroxy protecting groups. Such compounds are used in preparing pharmaceutical compositions and are useful in treating a variety of biological conditions.
提供了
化学式I的化合物,其中X1和X2分别由H或羟基保护基团独立选择。这些化合物用于制备药物组成物,并且在治疗各种
生物条件方面非常有用。