Systematic comparison of sets of (13)C NMR spectra that are potentially identical. Confirmation of the configuration of a cuticular hydrocarbon from the cane beetle Antitrogus parvulus.
Systematic comparison of sets of (13)C NMR spectra that are potentially identical. Confirmation of the configuration of a cuticular hydrocarbon from the cane beetle Antitrogus parvulus.
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DOI：
10.1021/jo5012027
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发表时间：
2014-08-15
期刊：
影响因子：
--
通讯作者：
Curran DP
中科院分区：
文献类型：
--
作者：
Basar N;Damodaran K;Liu H;Morris GA;Sirat HM;Thomas EJ;Curran DP
介绍了一种比较已知结构的两个(或多个)候选样品与未知结构的天然产物样品的~(13)C核磁共振谱的系统过程。这一过程是针对这样的情况而设计的，即所涉及的光谱可以合理地预期非常相似，甚至可能是相同的。它首先通过使用已公布的天然产物4，6，8，10，16，18-六甲基二十二烷的13C核磁共振数据集进行验证。然后介绍了相关天然产物4，6，8，10，16-五甲基二十二烷的两个候选异构体的立体选择性全合成，并应用该工艺确定了天然产物的构型为(4S，6R，8R，10S，16S)。即使这个异构体和它的(16R)-同分异构体之间的化学位移差只有±5-10 ppb(±0.005-0.01ppm)，这也是成功的。
A systematic process is introduced to compare 13C NMR spectra of two (or more) candidate samples of known structure to a natural product sample of unknown structure. The process is designed for the case where the spectra involved can reasonably be expected to be very similar, perhaps even identical. It is first validated by using published 13C NMR data sets for the natural product 4,6,8,10,16,18-hexamethyldocosane. Then the stereoselective total syntheses of two candidate isomers of the related 4,6,8,10,16-pentamethyldocosane natural product are described, and the process is applied to confidently assign the configuration of the natural product as (4S,6R,8R,10S,16S). This is accomplished even though the chemical shift differences between this isomer and its (16R)-epimer are only ±5–10 ppb (±0.005–0.01 ppm).
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DOI：
10.1002/anie.198701901
发表时间：
1987-03-01
期刊：
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH
影响因子：
--
作者：
BROWN, JM
通讯作者：
BROWN, JM
影响因子：
15
作者：
Denmark, Scott E.;Regens, Christopher S.;Kobayashi, Tetsuya
通讯作者：
Kobayashi, Tetsuya
影响因子：
3.2
作者：
Basar, Norazah;Donnelly, Sam;Thomas, Eric J.
通讯作者：
Thomas, Eric J.
影响因子：
1.8
作者：
BHUYAN, PJ;PRAJAPATI, D;SANDHU, JS
通讯作者：
SANDHU, JS
影响因子：
3.6
作者：
Chow, S;Fletcher, MT;Kitching, W
通讯作者：
Kitching, W