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Updated: Jul 23, 2025

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR

Published on: December 16, 2013

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一个ECD和NMR/DP4+计算管道用于结构修订和二纳基天然产品的阐明

Yihao Zhuang1,2, Fei Yang2, Arya Menon1

  • 1Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, 1600 Huron Parkway, NCRC B520, Ann Arbor, Michigan 48109, United States.

Journal of natural products
|July 18, 2023
PubMed
概括

确定复杂的天然产品结构,如diphenazines是具有挑战性的. 使用NMR/DP4+的新计算管道成功阐明了结构和的位置,有助于发现抑制真核转化启动因子4E (eIF4E) 的药物.

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¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)

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A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
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Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
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The 1D NMR spectrum of large and complex molecules like natural products has complicated splitting patterns and overlapping signals, which can be easily interpreted using 2-dimensional (2D) NMR. Unlike 1D NMR, 2D NMR has two frequency axes that provide the coupling information between the nucleus A and nucleus B in a molecule. The process from which 2D spectra are obtained has four steps.
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse....
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NMR Spectroscopy of Aromatic Compounds

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