(-)-(R_S)-(p-tolylsulfinyl)stigmasteryl isomethyl ether | 172376-34-0

• 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: (-)-(R_S)-(p-tolylsulfinyl)stigmasteryl isomethyl ether
• 英文别名: (1S,2R,5R,7R,8R,10S,11S,14R,15R)-14-[(Z,2S,5S)-5-ethyl-6-methyl-4-[(S)-(4-methylphenyl)sulfinyl]hept-3-en-2-yl]-8-methoxy-2,15-dimethylpentacyclo[8.7.0.02,7.05,7.011,15]heptadecane
• CAS: 172376-34-0
• 化学式: C₃₇H₅₆O₂S
• 分子量: 564.916
• InChiKey: RGQKVWYBIXYLHL-PROUGVSKSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  10.2
• 重原子数：
  40
• 可旋转键数：
  8
• 环数：
  6.0
• sp3杂化的碳原子比例：
  0.78
• 拓扑面积：
  45.5
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  (-)-(R_S)-(p-tolylsulfinyl)stigmasteryl isomethyl ether 在 甲基锂 、 叔丁基锂 作用下， 以 四氢呋喃 为溶剂， 反应 0.05h， 生成 stigmasterol methyl ether
  参考文献：
  名称：

  Highly Stereocontrolled Formal Synthesis of Brassinolide via Chiral Sulfoxide-Directed S_N2‘ Reactions

  摘要：

  An efficient stereocontrolled methodology for the preparation of the four contiguous chiral centers of the brassinosteroid side chain is described. Allylic mesyloxy sulfinyl steroids have been found to undergo highly stereoselective S(N)2' displacements when treated with cyanocuprates that provide the required acyclic stereocontrol in the key C-24 position of the steroidal side chain. Preparation of a direct precursor of brassinolide]I, as well as a precursor of naturally occurring (24R)-epibrassinolide, (+)-18, is carried out in two additional steps utilizing asymmetric dihydroxylations of(22E)-olefins (+)-2 and (+)-17. In this manner, a formal synthesis of this plant growth promoter has been completed, and the extension of the scope of this methodology has been explored providing a straightforward route to this family of steroids. Alternative routes to the key olefin (+)-2 are also outlined. Improved selectivity in the addition to aldehyde 7 for the preparation of the Cram (22R)-allylic hydroxy sulfoxides is achieved by controlling the chirality at sulfur or by a condensation-symmetric oxidation sequence employing the analogous vinyl sulfide reagent 22.

  DOI：

  10.1021/jo951264k
• 作为产物：
  描述：

  (+)-(22R,23E,R_S)-22-hydroxy-6β-methoxy-23-(p-tolylsulfinyl)-3α,5-cyclo-5α-cholest-23-ene 在 吡啶 作用下， 以 四氢呋喃 为溶剂， 反应 7.0h， 生成 (-)-(R_S)-(p-tolylsulfinyl)stigmasteryl isomethyl ether
  参考文献：
  名称：

  Highly Stereocontrolled Formal Synthesis of Brassinolide via Chiral Sulfoxide-Directed S_N2‘ Reactions

  摘要：

  An efficient stereocontrolled methodology for the preparation of the four contiguous chiral centers of the brassinosteroid side chain is described. Allylic mesyloxy sulfinyl steroids have been found to undergo highly stereoselective S(N)2' displacements when treated with cyanocuprates that provide the required acyclic stereocontrol in the key C-24 position of the steroidal side chain. Preparation of a direct precursor of brassinolide]I, as well as a precursor of naturally occurring (24R)-epibrassinolide, (+)-18, is carried out in two additional steps utilizing asymmetric dihydroxylations of(22E)-olefins (+)-2 and (+)-17. In this manner, a formal synthesis of this plant growth promoter has been completed, and the extension of the scope of this methodology has been explored providing a straightforward route to this family of steroids. Alternative routes to the key olefin (+)-2 are also outlined. Improved selectivity in the addition to aldehyde 7 for the preparation of the Cram (22R)-allylic hydroxy sulfoxides is achieved by controlling the chirality at sulfur or by a condensation-symmetric oxidation sequence employing the analogous vinyl sulfide reagent 22.

  DOI：

  10.1021/jo951264k