Lewis acid catalyzed acetylation of steroidal sapogenin was reinvestigated, and the previous assigned structures A, B and C of E/F ring opening products were rectified as 1, 2 and 3 according to X ray diffraction analysis.

• 重新研究了Lewis酸催化的甾体皂甙元E/F螺环乙酰化开环反应；并通过波谱分析和单晶X衍射修正了原指定结构.