Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    Electronic Resource
    Electronic Resource
    Mass spectra of benzotriazoles. Correlation with thermolytic and photolytic fragmentations (1970)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 4 (1970), S. 203-210 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The mass spectra of some alkyl, aryl and acyl benzotriazoles are reported and discussed on the basis of their thermolytic and photolytic fragmentation products. All benzotriazoles so far studied lose a molecule of nitrogen to give the intermediate radical cations upon electron-impact. Subsequently cyclization and a hydrogen migration lead them to the molecular ions of thermolytic and photolytic fragmentation products. A general rule for predicting the possibility of 1-3 hydrogen migration, based on a knowledge of the electronic state of the radical cation is proposed.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210040122
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Dual mechanisms for the fragmentation of 1-benzoylbenzotriazole upon electron impact (1980)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 15 (1980), S. 1-3 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The electron impact induced fragmentation of 1-benzoylbenzotriazole has been studied by 13C labelling experiments. It has been found that the loss of CO from the [M — N2]+· ions proceeds by two routes; about 78% of the ions decompose via the molecular ions of the corresponding thermal fragmentation product, 2-phenylbenzoxazole, and 22% via those of the corresponding photochemical fragmentation product, 6-phenanthridone.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210150103
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Cluster ions in the secondary ion mass spectrometry of choline and acetylcholine halides (1990)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 25 (1990), S. 109-114 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Liquid secondary ion mass spectra of choline and acetylcholine halides exhibit several series of cluster ions whose origins were investigated using B/E and B2/E linked-scan techniques. In the case of choline halides three series of cluster ions were identified as (Me3\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}CH2CH2OH + nM), (Me3\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}CH2CH2OMe + nM) and (Me3N\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}CH2CH2OH · Me3\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}CH2CH2O- + nM), while (CH3COOCH2CH2\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}Me3 + nM), (Me3\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}CH2CH2OH + nM) and (CH2 = CH\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^ + $\end{document}Me3 + nM) were observed in the spectra of acetylcholine halides. For these cluster ions, bimolecular reactions induced on ion bombardment under secondary ion mass spectrometric conditions are discussed.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210250205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Letters to the editor (1985)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 20 (1985), S. 642-645 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210201009
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Structures of [M-44]+ ions in the electron impact and fast atom bombardment mass spectra of the β-blocker nipradilol with a nitrate ester group (1990)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 25 (1990), S. 146-150 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Both electron impact (EI) and fast atom bombardment (liquid secondary ion mass spectrometry) (FAB(LSIMS)) spectra of tbe antihypertensive drug nipradilol (3,4-dihydro-8-(2-hydroxy-3-isopropylamino)propoxy-3-nitroxy-2 H-l-benzopyran) and it analogues exhibit intense [M - 44]+ peaks. However, high-resolution measurements and tandem mass spectrometric techniques clarified that the composition of the ion produced by EI is [M-C2H4O]+, whereas that of the ion produced by FAB(LSIMS) is [M - NO2 + 2H]+. FAB collision-activated dissociation-tandem mass spectrometry revealed that the structure of the latter ion corresponds to the MH+ of the hydrolysis product of the nitrate ester group.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210250305
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Gas phase electron ionization fragmentation of dextromethorphan and related quaternary ammonium salts (1984)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 11 (1984), S. 529-534 
    Details
    ISSN: 0306-042X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The in-beam electron ionization (EI) spectra of quaternary ammonium salts of dextromethorphan and piperidine consist of peaks arising both from thermal degradation products and from the fragmentation of the molecular cation [R4N]+. Mass-analysed ion kinetic energy and ion kinetic energy spectra indicate that several major ions believed to be thermally induced before EI are also produced directly from [R4N]+ fragmentation. However, the contribution of the direct fragmentation of [R4N]+ upon EI is small in comparison to that of the thermal degradation products. This behavior was observed in the conformationally flexible and rigid piperidinium rings studied.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bms.1200111007
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    In-beam electron impact mass spectrometry of amino sugars (1978)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 5 (1978), S. 578-581 
    Details
    ISSN: 0306-042X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Characteristics of in-beam electron impact ionization mass spectra of several amino sugars, which give barely detectable molecular ion peaks by the use of conventional direct inlet probes, are described. The spectra of these compounds almost always exhibited the M + 1 peak and the spectral features were apparently a combination of those of the conventional electron impact spectrum and some major peaks originating from the M + 1 ions. In the case of neamine, effects of the measurement conditions such as the source temperature, ionizing voltage, the position of the sample and time factors on the intensity of the M + 1 peak were examined. When the samples were mixed with ammonium chloride, the M + 1 peaks in the in-beam spectra were completely suppressed, while with aqueous ammonia, the abundance of the M + 1 peaks in creased by several times.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bms.1200051006
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...