Cholestane-3,22-diol, diacetate, (3b,5a,22S)- | 149951-19-9

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 类固醇和类固醇衍生物
• 英文名称: Cholestane-3,22-diol, diacetate, (3b,5a,22S)-
• 英文别名: (22S)-3β,22-Diacetoxy-5α-cholestane；3β,22α_F-diacetoxy-5α-cholestane；3β,22α_F-Diacetoxy-5α-cholestan
• CAS: 149951-19-9
• 化学式: C₃₁H₅₂O₄
• 分子量: 488.751
• InChiKey: SGCRGMRCDPCHBF-CQZPIQLCSA-N

物化性质

• 沸点：
  529.4±23.0 °C(Predicted)
• 密度：
  1.03±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  7.58
• 重原子数：
  35.0
• 可旋转键数：
  7.0
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.94
• 拓扑面积：
  52.6
• 氢给体数：
  0.0
• 氢受体数：
  4.0

反应信息

• 作为产物：
  描述：

  去氢表雄酮 在 platinum on activated charcoal 吡啶 、 potassium tert-butylate 、 氢气 、 二甲基氯化铝 作用下， 以 乙醚 、 乙醇 、 二氯甲烷 、 氯仿 、 乙酸乙酯 、 甲苯 为溶剂， 反应 42.0h， 生成 Cholestane-3,22-diol, diacetate, (3b,5a,22S)-
  参考文献：
  名称：

  Stereoselective construction of 22-oxygenated steroid side chains by dimethylaluminum chloride-mediated ene reactions of aldehydes

  摘要：

  Dimethylaluminum chloride-mediated ene reactions of aldehydes with (Z)-3beta-acetoxy-5,17(20)-pregnadiene (3) at low temperatures followed by acetylation of the resulting alcohols have been shown to produce stereoselectively 22-acetoxylated steroid derivatives in good to excellent yields. Interestingly, the stereochemical outcome of these ene reactions has been found to be dependent upon the size of the aldehyde employed; the less sterically demanding aldehydes such as 4-methylpentanal and cyclohexanecarboxaldehyde afford the (20alpha,22alpha)-22-acetoxy products (4a) stereoselectively, whereas the relatively congested aldehydes such as benzaldehyde and other aromatic aldehydes produce predominantly the (20alpha,22beta)-22-acetates (4b). This novel stereochemical observation has been rationalized in terms of the relative stabilities of the two most plausible transition states where the difference in the relative bulk between the R group of the aldehyde RCHO and the Me2AlCl coordinating to the aldehyde oxygen in an anti-fashion seems to be manifested in the stereochemical outcome at C-22 of the ene products.

  DOI：

  10.1021/jo00068a024