Structural Characterization and Differentiation of Isomeric ω-Bromoalkoxy Derivatives of (E)-Chalcone by Means of Mass Spectrometry

2008 ◽  
Vol 14 (1) ◽  
pp. 37-47 ◽  
Author(s):  
Zdzisława Nowakowska
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
Structural Characterization ◽  
Molecular Ions ◽  
Electron Ionization ◽  
Cone Voltage ◽  
Fragment Ions ◽  
The Difference ◽  
Derivatives Of

Mass spectrometry with electron ionization and electrospray ionization have been applied to characterize and differentiate the isomeric ortho-, meta- or para-( E)-bromoalkyloxychalcones 1–15. The difference in the values of μ1–μ5 (i.e. the ratio of abundances of the selected fragment ions to those of the molecular ions) in the series of isomeric chalcones studied and the so-called “in-source” fragmentation induced by increasing cone voltage have been found to be important and reliable indicators differentiating the isomers studied.

Liquid Secondary Ion Mass Spectrometry and Collision-induced Dissociation Mass Spectrometry of Sulfonamide Derivatives of meso-Tetraphenylporphyrin

1999 ◽  
Vol 03 (03) ◽  
pp. 172-179 ◽  
Author(s):  
M. ROSÁRIO M. DOMINGUES ◽  
M. GRAÇA SANTANA-MARQUES ◽  
A. J. FERRRER-CORREIA ◽  
AUGUSTO C. TOMÉ ◽  
MARIA G. P. M. S. NEVES ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectra ◽  
Secondary Ion Mass Spectrometry ◽  
Molecular Ions ◽  
Collision Induced Dissociation ◽  
Fragment Ions ◽  
Ion Mass Spectrometry ◽  
Derivatives Of ◽  
Secondary Ion

Liquid secondary ion mass spectrometry (LSIMS) and collision-induced dissociation (CID) were used for the characterization of sulfonamide derivatives of meso-tetraphenylporphyrin (TPP). The spectra obtained using LSIMS show abundant molecular ions and fragment ions from losses of the sulfonamide moieties. The main fragmentation observed in the LSI mass spectra and in the CID spectra of the protonated or cationized molecules involves the loss of one sulfonamide group. In addition, in the CID spectra of these compounds the fragment ions formed by the elimination of two, three and/or four sulfonamide groups are also observed. The CID spectra of the protonated or cationized molecules of these derivatives do not display the ions formed by the cleavage of the S - N bond which have been reported for other sulfonamide compounds. The LSI mass spectra and CID spectra of sulfonamide derivatives of meso-tetraphenylporphyrin provide an easy and reliable means of identification of the number and nature of sulfonamide groups in the porphyrinic ring.

Electrospray ionization mass spectrometry for identification and structural characterization of pregnane glycosides

2005 ◽  
Vol 19 (8) ◽  
pp. 1041-1052 ◽  
Author(s):  
Fabrizio Dal Piaz ◽  
Marinella De Leo ◽  
Alessandra Braca ◽  
Francesco De Simone ◽  
Ivano Morelli ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Ionization ◽  
Structural Characterization ◽  
Electrospray Ionization Mass Spectrometry ◽  
Ionization Mass Spectrometry ◽  
Ionization Mass

Continuous flow fast atom bombardment mass spectrometry of mononucleotides and their metal complexes

1989 ◽  
Vol 67 (5) ◽  
pp. 910-920 ◽  
Author(s):  
M. J. Bertrand ◽  
V. Benham ◽  
R. St-Louis ◽  
M. J. Evans
Keyword(s):  
Mass Spectrometry ◽  
Continuous Flow ◽  
Fast Atom Bombardment ◽  
Aqueous Media ◽  
Molecular Ions ◽  
Fragment Ions ◽  
Low Concentrations ◽  
Metal Adducts ◽  
Matrix Concentration

The mass spectra of mononucleotides and their metal adducts Na, K, Mg, Ca, Ni, Co, Cu, and Zn of guanosine 5′-monophosphate (5′-GMP) as well as H, Na, and Mg of adenosine 5′-monophosphate (5′-AMP) and H and Ni of inosine 5′-monophosphate (5′-IMP) have been obtained in low concentrations of matrix in water using continuous-flow fast atom bombardment. The results indicate that this technique is suitable for the analysis of these complexes in aqueous media and yields spectra that are highly characteristic of the compounds analyzed. Parent-molecular ions and structurally significant fragment ions are observed for all compounds studied and the different binding sites for the metal on the nucleotides can be isolated from the fragment ions. Experimental parameters influencing the quality of the spectra such as flow rate, matrix concentration, matrix nature, and analyte concentration have been studied and optimized. For the thirteen compounds studied, it appears that continuous-flow FAB is superior to conventional FAB and that good quality spectra can be obtained with as little as 0.5% of added matrix thus minimizing spectral interferences. Keywords: continuous flow FAB, FAB MS, mass spectrometry, nucleotides, metal-nucleotides.

Sign in / Sign up

Export Citation Format

Share Document