21-oxoisopteropodine | 134002-29-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吲哚里西啶
• 英文名称: 21-oxoisopteropodine
• 英文别名: methyl (1'R,3R,4'aR,5'aR,10'aS)-1'-methyl-2,10'-dioxospiro[1H-indole-3,6'-4a,5,5a,7,8,10a-hexahydro-1H-pyrano[3,4-f]indolizine]-4'-carboxylate
• CAS: 134002-29-2
• 化学式: C₂₁H₂₂N₂O₅
• 分子量: 382.416
• InChiKey: FSFVCJQXGSXULW-GMYZOUPFSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.8
• 重原子数：
  28
• 可旋转键数：
  2
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.48
• 拓扑面积：
  84.9
• 氢给体数：
  1
• 氢受体数：
  5

反应信息

• 作为反应物：
  描述：

  21-oxoisopteropodine 在 甲醇 、 aluminium hydride 、 sodium cyanoborohydride 、 溶剂黄146 作用下， 生成 isopteropodine
  参考文献：
  名称：

  Unified strategy for synthesis of indole and 2-oxindole alkaloids

  摘要：

  A concise and general entry to representative indole alkaloids of the yohimboid, heteroyohimboid, corynantheoid, and 2-oxindole classes has been developed exploiting a strategy that features intramolecular Diels-Alder reactions for the facile construction of the D/E ring subunits of the target alkaloids. The efficacy of the approach is first illustrated by a two-step total synthesis of the yohimboid alkaloid oxogambirtannine (2) from 22. Thus, the Diels-Alder substrate 25, which was prepared by nucleophilic addition of vinyl ketene acetal 24 to the intermediate N-acyliminium salt formed in situ upon reaction of 22 with 23, was heated in the presence of benzoquinone to give a mixture of diastereoisomeric cycloadducts 26 and 27; these adducts underwent spontaneous oxidation to furnish 2. In another application of the strategy, the [4 + 2] heterocyclization of 34a, which was formed upon nucleophilic addition of 1-[(trimethylsilyl)oxy]butadiene to the N-acyliminium salt generated in situ upon treatment of 22 with crotonyl chloride, afforded a mixture (ca. 9:1) of cycloadducts 35a and 36a. The major adduct 35a was converted to 42a using a general procedure for effecting beta-carbomethoxylation of enol ethers to give vinylogous carbonates. Subsequent reduction of 42a to the heteroyohimboid alkaloids (+/-)-tetrahydroalstonine (3) and (+/-)-cathenamine (4) was achieved by selective delivery of 2 or 1 equiv of hydride, respectively. When 42a was treated with sodium amide, stereoselective beta-elimination ensued to give 49, which was converted by chemoselective hydride reduction into the corynantheoid alkaloid (+/-)-geissoschizine (5). Facile access to alkaloids of the 2-oxindole family was realized by using a new protocol for achieving stereoselective, oxidative rearrangements of beta-carboline N(b) lactams into 3,3-disubstituted 2-oxindoles. Thus, exposure of 42a to tert-butyl hypochlorite followed by acid and silver ion induced rearrangement of the intermediate 3-chloroindolenine gave 50, with only traces of the C(7) epimer being detected. Hydride reduction of 50 gave (+/-)-isopteropodine (6), acid-catalyzed isomerization of which furnished an equilibrium mixture (1:3) of 6 and (+/-)-pteropodine (51). The stereochemical course of the intramolecular hetero-Diels-Alder reaction of 34a to give 35a and 36a as the only isolable cycloadducts was examined by computational analysis. The geometry of the six-atom transition state was established by semiempirical methods by using the standard closed-shell, restricted Hartree-Fock (RHF) version of the AM1 method. With use of this constrained geometry for the six-membered pericyclic array, the overall conformational energies for the four possible transition states 52-55 were minimized by MM2 calculations (MacroModel). The calculated relative energies of these transition states were in the order 52 < 53 < 54 < 55. Since the cyclization of 34a produced only 35a and 36a in an approximately 9:1 ratio via the respective transition states 52 and 53, these calculations correlated qualitatively with the experimental results.

  DOI：

  10.1021/ja00016a036
• 作为产物：
  描述：

  4,9-二氢-3H-吡啶并(3,4-B)吲哚 在 甲醇 、 高氯酸 、 2,6-二叔丁基-4-甲基吡啶 、 次氯酸叔丁酯 、 silver perchlorate 、 三乙胺 作用下， 以 四氢呋喃 、 二氯甲烷 、 均三甲苯 为溶剂， 反应 118.42h， 生成 21-oxoisopteropodine
  参考文献：
  名称：

  Unified strategy for synthesis of indole and 2-oxindole alkaloids

  摘要：

  A concise and general entry to representative indole alkaloids of the yohimboid, heteroyohimboid, corynantheoid, and 2-oxindole classes has been developed exploiting a strategy that features intramolecular Diels-Alder reactions for the facile construction of the D/E ring subunits of the target alkaloids. The efficacy of the approach is first illustrated by a two-step total synthesis of the yohimboid alkaloid oxogambirtannine (2) from 22. Thus, the Diels-Alder substrate 25, which was prepared by nucleophilic addition of vinyl ketene acetal 24 to the intermediate N-acyliminium salt formed in situ upon reaction of 22 with 23, was heated in the presence of benzoquinone to give a mixture of diastereoisomeric cycloadducts 26 and 27; these adducts underwent spontaneous oxidation to furnish 2. In another application of the strategy, the [4 + 2] heterocyclization of 34a, which was formed upon nucleophilic addition of 1-[(trimethylsilyl)oxy]butadiene to the N-acyliminium salt generated in situ upon treatment of 22 with crotonyl chloride, afforded a mixture (ca. 9:1) of cycloadducts 35a and 36a. The major adduct 35a was converted to 42a using a general procedure for effecting beta-carbomethoxylation of enol ethers to give vinylogous carbonates. Subsequent reduction of 42a to the heteroyohimboid alkaloids (+/-)-tetrahydroalstonine (3) and (+/-)-cathenamine (4) was achieved by selective delivery of 2 or 1 equiv of hydride, respectively. When 42a was treated with sodium amide, stereoselective beta-elimination ensued to give 49, which was converted by chemoselective hydride reduction into the corynantheoid alkaloid (+/-)-geissoschizine (5). Facile access to alkaloids of the 2-oxindole family was realized by using a new protocol for achieving stereoselective, oxidative rearrangements of beta-carboline N(b) lactams into 3,3-disubstituted 2-oxindoles. Thus, exposure of 42a to tert-butyl hypochlorite followed by acid and silver ion induced rearrangement of the intermediate 3-chloroindolenine gave 50, with only traces of the C(7) epimer being detected. Hydride reduction of 50 gave (+/-)-isopteropodine (6), acid-catalyzed isomerization of which furnished an equilibrium mixture (1:3) of 6 and (+/-)-pteropodine (51). The stereochemical course of the intramolecular hetero-Diels-Alder reaction of 34a to give 35a and 36a as the only isolable cycloadducts was examined by computational analysis. The geometry of the six-atom transition state was established by semiempirical methods by using the standard closed-shell, restricted Hartree-Fock (RHF) version of the AM1 method. With use of this constrained geometry for the six-membered pericyclic array, the overall conformational energies for the four possible transition states 52-55 were minimized by MM2 calculations (MacroModel). The calculated relative energies of these transition states were in the order 52 < 53 < 54 < 55. Since the cyclization of 34a produced only 35a and 36a in an approximately 9:1 ratio via the respective transition states 52 and 53, these calculations correlated qualitatively with the experimental results.

  DOI：

  10.1021/ja00016a036

文献信息

• MARTIN, STEPHEN F.;BENAGE, BRIGITTE;GERACI, LEO S.;HUNTER, JAMES E.;MORTI+, J. AMER. CHEM. SOC., 113,(1991) N6, C. 6161-6171
  作者：MARTIN, STEPHEN F.、BENAGE, BRIGITTE、GERACI, LEO S.、HUNTER, JAMES E.、MORTI+

  DOI：——

  日期：——
• Unified strategy for synthesis of indole and 2-oxindole alkaloids
  作者：Stephen F. Martin、James E. Hunter、Brigitte Benage、Leo S. Geraci、Michael Mortimore

  DOI：10.1021/ja00016a036

  日期：1991.7

  A concise and general entry to representative indole alkaloids of the yohimboid, heteroyohimboid, corynantheoid, and 2-oxindole classes has been developed exploiting a strategy that features intramolecular Diels-Alder reactions for the facile construction of the D/E ring subunits of the target alkaloids. The efficacy of the approach is first illustrated by a two-step total synthesis of the yohimboid alkaloid oxogambirtannine (2) from 22. Thus, the Diels-Alder substrate 25, which was prepared by nucleophilic addition of vinyl ketene acetal 24 to the intermediate N-acyliminium salt formed in situ upon reaction of 22 with 23, was heated in the presence of benzoquinone to give a mixture of diastereoisomeric cycloadducts 26 and 27; these adducts underwent spontaneous oxidation to furnish 2. In another application of the strategy, the [4 + 2] heterocyclization of 34a, which was formed upon nucleophilic addition of 1-[(trimethylsilyl)oxy]butadiene to the N-acyliminium salt generated in situ upon treatment of 22 with crotonyl chloride, afforded a mixture (ca. 9:1) of cycloadducts 35a and 36a. The major adduct 35a was converted to 42a using a general procedure for effecting beta-carbomethoxylation of enol ethers to give vinylogous carbonates. Subsequent reduction of 42a to the heteroyohimboid alkaloids (+/-)-tetrahydroalstonine (3) and (+/-)-cathenamine (4) was achieved by selective delivery of 2 or 1 equiv of hydride, respectively. When 42a was treated with sodium amide, stereoselective beta-elimination ensued to give 49, which was converted by chemoselective hydride reduction into the corynantheoid alkaloid (+/-)-geissoschizine (5). Facile access to alkaloids of the 2-oxindole family was realized by using a new protocol for achieving stereoselective, oxidative rearrangements of beta-carboline N(b) lactams into 3,3-disubstituted 2-oxindoles. Thus, exposure of 42a to tert-butyl hypochlorite followed by acid and silver ion induced rearrangement of the intermediate 3-chloroindolenine gave 50, with only traces of the C(7) epimer being detected. Hydride reduction of 50 gave (+/-)-isopteropodine (6), acid-catalyzed isomerization of which furnished an equilibrium mixture (1:3) of 6 and (+/-)-pteropodine (51). The stereochemical course of the intramolecular hetero-Diels-Alder reaction of 34a to give 35a and 36a as the only isolable cycloadducts was examined by computational analysis. The geometry of the six-atom transition state was established by semiempirical methods by using the standard closed-shell, restricted Hartree-Fock (RHF) version of the AM1 method. With use of this constrained geometry for the six-membered pericyclic array, the overall conformational energies for the four possible transition states 52-55 were minimized by MM2 calculations (MacroModel). The calculated relative energies of these transition states were in the order 52 < 53 < 54 < 55. Since the cyclization of 34a produced only 35a and 36a in an approximately 9:1 ratio via the respective transition states 52 and 53, these calculations correlated qualitatively with the experimental results.