D:B-Friedo-18β,19αH-lup-5-en-3β-ol was synthesized from friedelin via D:A-friedo-18β,19αH-lupan-3-one. The stereostructure of a 3α,4α-epoxide derived from the 3-one was determined by X-ray technique to show the 19αH configuration for both the epoxide and the 5-en-3β-ol, The disagreement of the spectral data of the synthetic 5-en-3β-ol with those of guimarenol is described.
                                    D:B-Friedo-18β,19αH-lup-5-en-3β-ol通过D:A-friedo-18β,19αH-lupan-3-one从friedelin合成而来。通过X射线技术确定了从3-one衍生的3α,4α-
环氧化物的立体结构,表明
环氧化物和5-en-3β-ol的19αH构型。描述了合成5-en-3β-ol的光谱数据与guimarenol的光谱数据之间的差异。