ethyl (2E,6E)-3-[(2)H3]methyl-7,11-dimethylundeca-2,6,10-trienoate | 1142409-57-1

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 异戊烯醇脂质
• 英文名称: ethyl (2E,6E)-3-[(2)H3]methyl-7,11-dimethylundeca-2,6,10-trienoate
• CAS: 1142409-57-1
• 化学式: C₁₇H₂₈O₂
• 分子量: 267.384
• InChiKey: RAVLTUCAFRTDRY-SYMWTWIUSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.97
• 重原子数：
  19.0
• 可旋转键数：
  9.0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.59
• 拓扑面积：
  26.3
• 氢给体数：
  0.0
• 氢受体数：
  2.0

反应信息

• 作为反应物：
  描述：

  ethyl (2E,6E)-3-[(2)H3]methyl-7,11-dimethylundeca-2,6,10-trienoate 在 lithium aluminium tetrahydride 、 recombinant (+)-cadinene synthase from Gossypium arboreum 、 甲基磺酰氯 、 lithium bromide 、 magnesium chloride 、 1,4-二巯基-2,3-丁二醇 作用下， 以 四氢呋喃 、 乙醚 、 正戊烷 为溶剂， 反应 24.5h， 生成 [15,15,15-(2)H3]-δ-cadinene
  参考文献：
  名称：

  A 1,6-Ring Closure Mechanism for (+)-δ-Cadinene Synthase?

  摘要：

  Recombinant (+)-delta-cadinene synthase (DCS) from Gossypium arboreum catalyzes the metal-dependent cyclization of (E,E)-farnesyl diphosphate (FDP) to the cadinane sesquiterpene delta-cadinene, the parent hydrocarbon of cotton phytoalexins such as gossypol. In contrast to some other sesquiterpene cyclases, DCS carries out this transformation with >98% fidelity but, as a consequence, leaves no mechanistic traces of its mode of action. The formation of (+)-delta-cadinene has been shown to occur via the enzyme-bound intermediate (3R)-nerolidyl diphosphate (NDP), which in turn has been postulated to be converted to cis-germacradienyl cation after a 1,10-cyclization. A subsequent 1,3-hydride shift would then relocate the carbocation within the transient macrocycle to expedite a second cyclization that yields the cadinenyl cation with the correct cis stereochemistry found in (+)-delta-cadinene. An elegant 1,10-mechanistic pathway that avoids the formation of (3R)-NDP has also been suggested. In this alternative scenario, the final cadinenyl cation is proposed to be formed through the intermediacy of trans, trans-germacradienyl cation and germacrene D. In addition, an alternative 1,6-ring closure mechanism via the bisabolyl cation has previously been envisioned. We report here a detailed investigation of the catalytic mechanism of DCS using a variety of mechanistic probes including, among others, deuterated and fluorinated FDPs. Farnesyl diphosphate analogues with fluorine at C2 and C10 acted as inhibitors of DCS, but intriguingly, after prolonged overnight incubations, they yielded 2F-germacrene(s) and a 10F-humulene, respectively. The observed 1,10-, and to a lesser extent, 1,11-cyclization activity of DCS with these fluorinated substrates is consistent with the postulated macrocyclization mechanism(s) en route to (+)-delta-cadinene. On the other hand, mechanistic results from incubations of DCS with 6F-FPP, (2Z,6E)-FDP, neryl diphosphate, 6,7-dihydro-FDP, and NDP seem to be in better agreement with the potential involvement of the alternative biosynthetic 1,6-ring closure pathway. In particular, the strong inhibition of DCS by 6F-FDP, coupled to the exclusive bisabolyl- and terpinyl-derived product profiles observed for the DCS-catalyzed turnover of (2Z,6E)-farnesyl and neryl diphosphates, suggested the intermediacy of alpha-bisabolyl cation. DCS incubations with enantiomerically pure [1-H-2(1)](1R)-FDP revealed that the putative bisabolyl-derived 1,6-pathway proceeds through (3R)-nerolidyl diphosphate (NDP), is consistent with previous deuterium-labeling studies, and accounts for the cis stereochemistry characteristic of cadinenyl-derived sesquiterpenes. While the results reported here do not unambiguously rule in favor of 1,6- or 1,10-cyclization, they demonstrate the mechanistic versatility inherent to DCS and highlight the possible existence of multiple mechanistic pathways.

  DOI：

  10.1021/ja211820p
• 作为产物：
  描述：

  香叶基溴 在 正丁基锂 、 二异丁基氢化铝 、 magnesium 、 二异丙胺 、 2-碘酰基苯甲酸 作用下， 以 四氢呋喃 、 乙醚 、 正己烷 、 二氯甲烷 、 二甲基亚砜 为溶剂， 反应 12.33h， 生成 ethyl (2E,6E)-3-[(2)H3]methyl-7,11-dimethylundeca-2,6,10-trienoate 、
  参考文献：
  名称：

  Cleistantha-8,12-二烯形成过程中具有欺骗性的复杂性

  摘要：

  发现大麦二萜合酶 (HvKSL4) 可产生 (14 S )-cleistantha-8,12-二烯 ( 1 )。近乎平面的 cyclohexa-1,4-diene 构型的形成使环为芳构化做好了准备，但需要通过复杂的能量景观进行一系列看似复杂的重排，如本文通过量子化学计算和标记研究所阐明的那样。

  DOI：

  10.1021/acs.orglett.2c00680