Electron impact studies. I. High resolution mass spectra of some unsaturated cyclic ketones

1966 ◽  
Vol 19 (9) ◽  
pp. 1619 ◽  
Author(s):  
JH Bowie
Keyword(s):  
High Resolution ◽  
Electron Impact ◽  
Mass Spectra ◽  
Cyclic Ketones ◽  
Mass Measurements ◽  
Exact Mass ◽  
Characteristic Fragmentation ◽  
Fragmentation Processes ◽  
Resolution Mass

The mass spectra of some 2-cyclohexen-1-ones, tetralones, and indanones have been investigated. The characteristic fragmentation processes, substantiated by appropriate metastable peaks, exact mass measurements, and in some cases by deuterium labelling studies, greatly facilitate the determination of both the type of system and the position of substituents on that system.

Electron impact studies of 4a-Methyl-4,4a-dihydrophenanthren-2(3H)-one and related phenanthrones

1976 ◽  
Vol 29 (12) ◽  
pp. 2731
Author(s):  
E Njau
Keyword(s):  
High Resolution ◽  
Electron Impact ◽  
Mass Spectra ◽  
Fragmentation Pattern ◽  
Mass Measurements ◽  
Impact Studies ◽  
High Resolution Mass ◽  
Fragmentation Processes ◽  
Resolution Mass

The mass spectra of 4a-methyl-4,4a-dihydrophenanthren-2(3H)-one and closely related phenanthrenones have been studied. The suggested fragmentation processes, substantiated by high-resolution mass measurements and appropriate metastable peaks, are shown to be characteristic of compounds with the same hydro-oxo-phenanthrene chromophore. 2-Cinnamylidene-6-methyl-cyclohexanone possessing a similar chromophore is also shown to exhibit a comparable fragmentation pattern.

Mass spectra of spermatheridine alkaloids. The structure of moschatoline

1967 ◽  
Vol 20 (7) ◽  
pp. 1403 ◽  
Author(s):  
IRC Bick ◽  
JH Bowie ◽  
GK Douglas
Keyword(s):  
Mass Spectra ◽  
Mass Measurements ◽  
Exact Mass ◽  
Deuterium Labelling ◽  
System A ◽  
Tetracyclic System ◽  
Characteristic Fragmentation ◽  
Fragmentation Processes

The mass spectra of a series of alkaloids of the spermatheridine group, together with those of their alkoxy derivatives, are reported and discussed. The characteristic fragmentation processes, substantiated by appropriate metastable peaks, exact mass measurements, and in some cases by deuterium labelling, facilitate the location of substituents in the tetracyclic system. A structure for moschatoline is deduced from a consideration of the mass spectra of its derivatives.

Electron impact studies. II. Mass spectra of quercetagetin derivatives

1966 ◽  
Vol 19 (9) ◽  
pp. 1627 ◽  
Author(s):  
JH Bowie ◽  
DW Cameron
Keyword(s):  
Electron Impact ◽  
Mass Spectra ◽  
Mass Measurements ◽  
Exact Mass ◽  
Deuterium Labelling ◽  
Impact Studies ◽  
Metastable Ions ◽  
Fragmentation Processes

The mass spectra of 11 quercetagetin derivatives are reported and discussed. The spectra are generally simple and amenable to analysis. 4 number of fragmentation processes have been substantiated by exact mass measurements, appropriate metastable ions, and deuterium labelling.

Electron impact studies. XXXI. Skeletal-rearrangement fragments in the mass spectra of anils

1968 ◽  
Vol 21 (8) ◽  
pp. 2021 ◽  
Author(s):  
JH Bowie ◽  
RG Cooks ◽  
JW Fisher ◽  
T McL Spotswood
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Electron Impact ◽  
Mass Spectra ◽  
General Type ◽  
High Resolution Mass Spectrometry ◽  
Aromatic Aldehydes ◽  
Skeletal Rearrangement ◽  
Rearrangement Processes ◽  
Resolution Mass

Skeletal-rearrangement fragments are observed in the mass spectra of all anils derived from aromatic aldehydes. The rearrangement processes have been studied by high-resolution mass spectrometry and in certain cases by deuterium labelling. All processes are of the general type [ABC]+ → [AC]+ +B.

scholarly journals Benzodiazepine Analogues. Part 20. Mass Spectrometric Analysis of Benzoxathiepine Derivatives

1999 ◽  
Vol 23 (9) ◽  
pp. 584-585
Author(s):  
Aifheli C. Gelebe ◽  
Perry T. Kaye
Keyword(s):  
High Resolution ◽  
Electron Impact ◽  
Mass Spectra ◽  
Mass Spectrometric ◽  
Mass Spectrometric Analysis ◽  
Spectrometric Analysis ◽  
Low Resolution ◽  
Fragmentation Patterns ◽  
Resolution Mass

Fragmentation patterns in the electron-impact (El) mass spectra of benzoxathiepine derivatives are elucidated using a combination of high-resolution and comparative low-resolution mass spectrometric analysis.

pParse: A method for accurate determination of monoisotopic peaks in high-resolution mass spectra

PROTEOMICS ◽  
2011 ◽  
Vol 12 (2) ◽  
pp. 226-235 ◽  
Author(s):  
Zuo-F ei Yuan ◽  
Chao Liu ◽  
Hai-Peng Wang ◽  
Rui-Xiang Sun ◽  
Yan Fu ◽  
...  
Keyword(s):  
High Resolution ◽  
Mass Spectra ◽  
Accurate Determination ◽  
High Resolution Mass ◽  
Resolution Mass

Electron impact studies. XII. Mass spectra of substituted imidazoles

1967 ◽  
Vol 20 (8) ◽  
pp. 1613 ◽  
Author(s):  
JH Bowie ◽  
RG Cooks ◽  
S Lawesson ◽  
G Schroll
Keyword(s):  
Mass Spectrometry ◽  
Structure Elucidation ◽  
Mass Spectra ◽  
Molecular Ions ◽  
Skeletal Rearrangement ◽  
Mass Measurements ◽  
Exact Mass ◽  
Metastable Ions ◽  
Characteristic Fragmentation ◽  
Fragmentation Patterns

The mass spectra of 37 imidazoles are reported and discussed. The spectra exhibit pronounced molecular ions and characteristic fragmentation patterns. The fragmentation modes have been substantiated by deuterium labelling, exact mass measurements, and appropriate metastable ions. Skeletal rearrangement fragments are rare in these spectra; consequently mass spectrometry is useful for structure elucidation of imidazoles.

Determination of Empirical Formulae by Precision Mass Measurements

1964 ◽  
Vol 18 (4) ◽  
pp. 102-107 ◽  
Author(s):  
J. van Katwijk
Keyword(s):  
High Resolution ◽  
Mass Spectrometer ◽  
Trial And Error ◽  
Mass Measurements ◽  
Mass Data ◽  
Factors Influencing ◽  
High Resolution Mass Spectrometer ◽  
Measured Mass ◽  
Resolution Mass

A method is presented for the determination of empirical formulae consistent with precision mass data measured with a high-resolution mass spectrometer. It involves some simple calculations and a table, and eliminates tedious trial and error procedures Factors influencing the number of possible formulae obtained for a measured mass value arc discussed

Exploring the Active Compounds of Traditional Mongolian Medicine Agsirga in Intervention of Novel Coronavirus (2019-nCoV) Based on HPLC-Q-Exactive-MS/MS and Molecular Docking Method

2020 ◽  
Author(s):  
Jie Cheng ◽  
Yuchen Tang ◽  
Baoquan Bao ◽  
Ping Zhang
Keyword(s):  
Mass Spectrometry ◽  
Molecular Docking ◽  
High Resolution ◽  
Mass Spectra ◽  
High Resolution Mass Spectrometry ◽  
Structural Formula ◽  
Active Compounds ◽  
High Resolution Mass ◽  
Q Exactive ◽  
Resolution Mass

<p><a></a><a></a><a></a><a><b>Objective</b></a>: To screen all compounds of Agsirga based on the HPLC-Q-Exactive high-resolution mass spectrometry and find potential inhibitors that can respond to 2019-nCoV from active compounds of Agsirga by molecular docking technology.</p> <p><b>Methods</b>: HPLC-Q-Exactive high-resolution mass spectrometry was adopted to identify the complex components of Mongolian medicine Agsirga, and separated by the high-resolution mass spectrometry Q-Exactive detector. Then the Orbitrap detector was used in tandem high-resolution mass spectrometry, and the related molecular and structural formula were found by using the chemsipider database and related literature, combined with precise molecular formulas (errors ≤ 5 × 10<sup>−6</sup>) , retention time, primary mass spectra, and secondary mass spectra information, The fragmentation regularities of mass spectra of these compounds were deduced. Taking ACE2 as the receptor and deduced compounds as the ligand, all of them were pretreated by discover studio, autodock and Chem3D. The molecular docking between the active ingredients and the target protein was studied by using AutoDock molecular docking software. The interaction between ligand and receptor is applied to provide a choice for screening anti-2019-nCoV drugs.</p> <p><b>Result</b>: Based on the fragmentation patterns of the reference compounds and consulting literature, a total of 96 major alkaloids and stilbenes were screened and identified in Agsirga by the HPLC-Q-Exactive-MS/MS method. Combining with molecular docking, a conclusion was got that there are potential active substances in Mongolian medicine Agsirga which can block the binding of ACE2 and 2019-nCoV at the molecular level.</p>

Determination of quaternary ammonium compounds in food products by the method of ultra-performance liquid chromatography/high resolution mass-spectrometry

2020 ◽  
Vol 86 (8) ◽  
pp. 23-31
Author(s):  
V. G. Amelin ◽  
D. S. Bolshakov
Keyword(s):  
Mass Spectrometry ◽  
High Resolution ◽  
Quaternary Ammonium ◽  
High Resolution Mass Spectrometry ◽  
Food Products ◽  
Quaternary Ammonium Compounds ◽  
High Resolution Mass ◽  
Ammonium Compounds ◽  
Resolution Mass

The goal of the study is developing a methodology for determination of the residual amounts of quaternary ammonium compounds (QAC) in food products by UHPLC/high-resolution mass spectrometry after water-acetonitrile extraction of the determined components from the analyzed samples. The identification and determination of QAC was carried out on an «UltiMate 3000» ultra-high-performance liquid chromatograph (Thermo Scientific, USA) equipped with a «maXis 4G» high-resolution quadrupole-time-of-flight mass spectrometric detector and an ion spray «ionBooster» source (Bruker Daltonics, Germany). Samples of milk, cheese (upper cortical layer), dumplings, pork, chicken skin and ground beef were used as working samples. Optimal conditions are specified for chromatographic separation of the mixture of five QAC, two of them being a mixture of homologues with a linear structure (including isomeric forms). The identification of QAC is carried out by the retention time, exact mass of the ions, and coincidence of the mSigma isotopic distribution. The limits for QAC detection are 0.1 – 0.5 ng/ml, the determination limits are 1 ng/ml for aqueous standard solutions. The determinable content of QAC in food products ranges within 1 – 100 ng/g. The results of analysis revealed the residual amount of QAC present in all samples, which confirms data of numerous sources of information about active use of QAC-based disinfectants in the meat and dairy industry. The correctness of the obtained results is verified by introduction of the additives in food products at a level of 10 ng/g for each QAC. The relative standard deviation of the analysis results does not exceed 0.18. The duration of the analysis is 30 – 40 min.

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