多选题:螺旋甾烷型皂苷的结构特征有

题目内容:
螺旋甾烷型皂苷的结构特征有 A.B/C和C/D环反式稠合
B.A/B环反式也有顺式稠合
C.C-20位的甲基为β构型
D.C-20位的甲基为a构型
E.C-25位的甲基为α或β构型
参考答案:
答案解析:

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