(3R,5S,15R,20R)-5-carboxy-17,18-didehydroalloyohimbane | 158146-62-4

• 分子结构分类: 有机化合物 - 生物碱及其衍生物 - 哈马拉生物碱
• 英文名称: (3R,5S,15R,20R)-5-carboxy-17,18-didehydroalloyohimbane
• CAS: 158146-62-4
• 化学式: C₂₀H₂₂N₂O₂
• 分子量: 322.407
• InChiKey: SSZNSZLICXONAJ-OBQMCUGOSA-N

物化性质

• 沸点：
  555.4±50.0 °C(predicted)
• 密度：
  1.34±0.1 g/cm3(Temp: 20 °C; Press: 760 Torr)(predicted)

反应信息

• 作为反应物：
  描述：

  (3R,5S,15R,20R)-5-carboxy-17,18-didehydroalloyohimbane 在 ammonium hydroxide 、 1-羟基苯并三唑 、 盐酸-N-乙基-Nˊ-(3-二甲氨基丙基)碳二亚胺 作用下， 以 N,N-二甲基甲酰胺 为溶剂， 反应 5.0h， 以64%的产率得到(3R,5S,15R,20R)-5-carbamoyl-17,18-didehydroalloyohimbane
  参考文献：
  名称：

  Symmetry-Driven Synthesis of Indole Alkaloids: Asymmetric Total Syntheses of (+)-Yohimbine, (-)-Yohimbone, (-)-Yohimbane, and (+)-Alloyohimbane

  摘要：

  Total asymmetric syntheses of the target alkaloids are reported. The syntheses involve the preparation of enantiomerically pure (S,S)-1,3,3a,4,7,7a-hexahydro-2(H)-inden-2-one 7 and its meso isomer 5. Each ketone is then converted into a ring-expanded lactam using an oxaziridine synthesis/rearrangement protocol. The applications of Bischler-Napieralski ring constructions along with appropriate functional group transformations afford enantiomerically enriched alloyohimbane or yohimbane from the meso- or C-2-symmetric ketones, respectively. A cis-5,6-diacetoxy compound (18) derived from the (S,S)-ketone served as the starting material for the total syntheses of the more highly functionalized alkaloids. Accordingly, a site-specific insertion of the indole-containing side chain was accomplished via stereoselective formation of an oxaziridine followed by its stereospecific rearrangement. The selectivity of this sequence allowed for the differentiation of alcohols at C-17 and C-18 (yohimbine numbering) and the synthesis of Delta 18,19-yohimbone. This alpha,beta-unsaturated ketone was converted into either (-)-yohimbone or (+)-yohimbine using standard chemistry.

  DOI：

  10.1021/ja00099a019
• 作为产物：
  描述：

  (3R,5S,15R,20R)-5-carbomethoxy-17,18-didehydroalloyohimbane 在 sodium hydroxide 作用下， 以 甲醇 为溶剂， 反应 48.0h， 以88%的产率得到(3R,5S,15R,20R)-5-carboxy-17,18-didehydroalloyohimbane
  参考文献：
  名称：

  Symmetry-Driven Synthesis of Indole Alkaloids: Asymmetric Total Syntheses of (+)-Yohimbine, (-)-Yohimbone, (-)-Yohimbane, and (+)-Alloyohimbane

  摘要：

  Total asymmetric syntheses of the target alkaloids are reported. The syntheses involve the preparation of enantiomerically pure (S,S)-1,3,3a,4,7,7a-hexahydro-2(H)-inden-2-one 7 and its meso isomer 5. Each ketone is then converted into a ring-expanded lactam using an oxaziridine synthesis/rearrangement protocol. The applications of Bischler-Napieralski ring constructions along with appropriate functional group transformations afford enantiomerically enriched alloyohimbane or yohimbane from the meso- or C-2-symmetric ketones, respectively. A cis-5,6-diacetoxy compound (18) derived from the (S,S)-ketone served as the starting material for the total syntheses of the more highly functionalized alkaloids. Accordingly, a site-specific insertion of the indole-containing side chain was accomplished via stereoselective formation of an oxaziridine followed by its stereospecific rearrangement. The selectivity of this sequence allowed for the differentiation of alcohols at C-17 and C-18 (yohimbine numbering) and the synthesis of Delta 18,19-yohimbone. This alpha,beta-unsaturated ketone was converted into either (-)-yohimbone or (+)-yohimbine using standard chemistry.

  DOI：

  10.1021/ja00099a019