4,4-dimethylcholesta-1,5-diene-3,7-dione | 145803-20-9

• 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: 4,4-dimethylcholesta-1,5-diene-3,7-dione
• 英文别名: (8S,9S,10R,13R,14S,17R)-4,4,10,13-tetramethyl-17-[(2R)-6-methylheptan-2-yl]-8,9,11,12,14,15,16,17-octahydrocyclopenta[a]phenanthrene-3,7-dione
• CAS: 145803-20-9
• 化学式: C₂₉H₄₄O₂
• 分子量: 424.667
• InChiKey: OZBSNINGLWSMRQ-DSGQGMSSSA-N

物化性质

• 沸点：
  530.2±50.0 °C(Predicted)
• 密度：
  1.02±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  8.3
• 重原子数：
  31
• 可旋转键数：
  5
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.79
• 拓扑面积：
  34.1
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  4,4-dimethylcholesta-1,5-diene-3,7-dione 在 偶氮二异丁腈 、 三正丁基氢锡 作用下， 以 苯 为溶剂， 反应 24.0h， 以38%的产率得到4,4-dimethylcholest-5-ene-3,7-dione
  参考文献：
  名称：

  Approaches to the synthesis of 1.alpha.,5.alpha.-cyclosteroids. 3. Synthesis of a novel 1.alpha.,5.alpha.-cyclocholestane

  摘要：

  The synthesis of 4,4-dimethyl-1alpha,5alpha-cyclocholesta-3,7-dione (11), by lithium- or ytterbium-liquid ammonia reduction of the bis-alpha,beta-unsaturated ketone,4,4-dimethylcholesta-1,5-diene-3,7-dione (10), is described. The chemistry of the reductive cyclization is discussed. The H-1 NMR spectra of the corresponding dihydroxy derivatives of 11 reveal an unusually high-field signal due to H-9. X-ray diffraction analysis of the 7beta-monool 13a indicates that ring B of the steroid nucleus is in a boat conformation and that H-9 partially eclipses the C-1-C-10 bond of the cyclopropyl ring. An anisotropic ring current effect is postulated to account for the chemical shifts of H-9 in these cyclosteroids. The chemistry of these compounds is described.

  DOI：

  10.1021/jo00056a012
• 作为产物：
  描述：

  4,4-dimethylcholesta-1,5-dien-3-one 在 N-溴代丁二酰亚胺(NBS) 、 calcium carbonate 作用下， 以 1,4-二氧六环 、 水 为溶剂， 反应 1.0h， 以86%的产率得到4,4-dimethylcholesta-1,5-diene-3,7-dione
  参考文献：
  名称：

  Approaches to the synthesis of 1.alpha.,5.alpha.-cyclosteroids. 3. Synthesis of a novel 1.alpha.,5.alpha.-cyclocholestane

  摘要：

  The synthesis of 4,4-dimethyl-1alpha,5alpha-cyclocholesta-3,7-dione (11), by lithium- or ytterbium-liquid ammonia reduction of the bis-alpha,beta-unsaturated ketone,4,4-dimethylcholesta-1,5-diene-3,7-dione (10), is described. The chemistry of the reductive cyclization is discussed. The H-1 NMR spectra of the corresponding dihydroxy derivatives of 11 reveal an unusually high-field signal due to H-9. X-ray diffraction analysis of the 7beta-monool 13a indicates that ring B of the steroid nucleus is in a boat conformation and that H-9 partially eclipses the C-1-C-10 bond of the cyclopropyl ring. An anisotropic ring current effect is postulated to account for the chemical shifts of H-9 in these cyclosteroids. The chemistry of these compounds is described.

  DOI：

  10.1021/jo00056a012

文献信息

• Approaches to the synthesis of 1.alpha.,5.alpha.-cyclosteroids. 3. Synthesis of a novel 1.alpha.,5.alpha.-cyclocholestane
  作者：Paris E. Georghiou、Yi Ren、John N. Bridson

  DOI：10.1021/jo00056a012

  日期：1993.2

  The synthesis of 4,4-dimethyl-1alpha,5alpha-cyclocholesta-3,7-dione (11), by lithium- or ytterbium-liquid ammonia reduction of the bis-alpha,beta-unsaturated ketone,4,4-dimethylcholesta-1,5-diene-3,7-dione (10), is described. The chemistry of the reductive cyclization is discussed. The H-1 NMR spectra of the corresponding dihydroxy derivatives of 11 reveal an unusually high-field signal due to H-9. X-ray diffraction analysis of the 7beta-monool 13a indicates that ring B of the steroid nucleus is in a boat conformation and that H-9 partially eclipses the C-1-C-10 bond of the cyclopropyl ring. An anisotropic ring current effect is postulated to account for the chemical shifts of H-9 in these cyclosteroids. The chemistry of these compounds is described.