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Updated: Jul 13, 2026

Determination of the Gas-phase Acidities of Oligopeptides
11:00

Determination of the Gas-phase Acidities of Oligopeptides

Published on: June 24, 2013

4-ヒドロキシピリミジンとそのケトン性形態のガス相タウトメア均衡:フリージェットミリ波スペクトロスコピーの研究

Raquel Sanchez1, B Michela Giuliano, Sonia Melandri

  • 1Dipartimento di Chimica "G. Ciamician" dell'Università, Via Selmi 2, I-40126 Bologna, Italy.

Journal of the American Chemical Society
|April 24, 2007
PubMed
まとめ

この研究では,ミリ波スペクトロスコーピーを用いて,4-ヒドロキシピリミジン (4HP) タウトマーを分析した. cis-4-hydroxypyrimidineと4-pyrimidinoneの形態が特定され,4-pyrimidinoneはより安定したタウトメールである.

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Mass Spectrum01:23

Mass Spectrum

A mass spectrum is the graphical representation of the relative abundance of the charged fragments in an analyte plotted against their mass-to-charge ratio (m/z). The plot's x-axis represents the ratio of the mass of the charged fragment to the number of charges it carries. The y axis of the plot represents the relative abundance of each charged species. The relative abundance is calculated from the signal intensity of each charged species recorded at the detector. The most intense signal (the...
Mass Spectrometry of Amines01:15

Mass Spectrometry of Amines

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Mass Spectrometry: Alkyne Fragmentation00:53

Mass Spectrometry: Alkyne Fragmentation

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Mass Spectrometry: Amine Fragmentation00:55

Mass Spectrometry: Amine Fragmentation

Amines can be identified using mass spectroscopy based on their characteristic fragmentation patterns. The molecular ions of amines undergo fragmentation via ⍺-cleavage. The ⍺-cleavage of the carbon-carbon bonds in amines generates an alkyl radical and resonance-stabilized nitrogen-containing cation.
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Mass Spectrometry: Carboxylic Acid, Ester, and Amide Fragmentation01:01

Mass Spectrometry: Carboxylic Acid, Ester, and Amide Fragmentation

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For example, the fragmentation of...
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Mass Spectrum: Interpretation

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