Synthesis and fast atom bombardment mass spectrometry of the coordination complexes of the ligand 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane

1989 ◽  
Vol 67 (5) ◽  
pp. 797-803 ◽  
Author(s):  
Cindy Lee MacLaurin ◽  
Jack Martin Miller ◽  
Mary Frances Richardson
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Spectroscopic Properties ◽  
Coordination Complexes ◽  
Negative Ion ◽  
Successful Technique ◽  
Negative Ion Mode ◽  
Positive Ion ◽  
Fab Mass Spectra

Metal complexes containing the ligand 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazatetradecane were synthesized and characterized using electron impact (EI) and fast atom bombardment (FAB). The FAB mass spectra were obtained in positive and negative ion mode. FAB in the positive ion mode proved to be the most successful technique for the identification of these compounds. The majority of the FAB spectra obtained were structurally informative, although not all showed molecular (M+) or quasimolecular ([M + H]+) ions. The fragmentations observed were characteristic of the ligands and the metal, and were interpreted based on the chemical and spectroscopic properties of these compounds. Keywords: FAB mass spectroscopy, tetraazacyclotetradecane complexes.

Fast Atom Bombardment Mass Spectra of Some N-α-(t-Butoxycarbonyl)-O-(diorganylphosphono)-L-serines and O-(Diorganylphosphono)seryl-Containing Dipeptides and Tripeptides

1994 ◽  
Vol 47 (2) ◽  
pp. 229 ◽  
Author(s):  
JW Perich ◽  
I Liepa ◽  
AL Chaffee ◽  
RB Johns
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrum ◽  
High Intensity ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Molecular Ions ◽  
Operating Conditions ◽  
Negative Ion ◽  
The Matrix ◽  
Positive Ion

Positive and negative ion fast atom bombardment ( f.a.b .) mass spectrometry were found to be useful methods for the analysis and structural characterization of five Nα-(t- butoxycarbonyl )-O-( diorganylphosphono )-L- serines ( organyl = Ph, Et, Me, Bzl , But), especially in the case of the sensitive benzyl and t-butyl phosphono derivatives. Under positive ion operating conditions, high intensity pseudo-molecular ions were obtained in the f.a.b . mass spectra, and the fragmentation pathway of the phenyl, ethyl and methyl derivatives was established by parent/daughter linked scanning studies to involve (a) the two-step loss of the t- butoxycarbonyl group, (b) loss of the amino acid as the neutral fragment from the [MH]+, [MH-56]+, [MH-100]+ and [MH-146]+ ions by a four- centred β-elimination rearrangement, and (c) cleavage of the phosphono phenyl and ethyl groups from only the [(RO)2P(OH)2]+ and [NH=CHCH2PO3R2+H]+ fragments. Parent/daughter linked scanning studies of the benzyl derivative showed that the prominent fragmentation involved loss of the benzyl group as the tropylium ion and that the 'apparent' [MH-90]+ peak observed in its f.a.b. mass spectrum resulted from cleavage of the phosphono benzyl group in the matrix during the bombardment process. In the case of the t-butyl derivative, parent/daughter linked scanning studies showed that the prominent fragmentation involved successive 'in-flight' loss of the phosphono t-butyl groups as isobutene. Negative ion f.a.b. mass spectrometry of the five derivatives gave f.a.b. mass spectra which displayed distinct [M-H]- anions along with high intensity [M-H-R]- and [(RO)2PO2]- fragment anions, the f.a.b . mass spectrum of the t-butyl derivative containing an additional [M-H-But-But]- fragment anion. Parent/daughter linked scanning studies established that the majority of the observed fragment anions resulted from extensive fragmentation of the Boc -Ser(PO3R2)-OH derivatives in the matrix phase followed by sputtering of the resultant fragments into the gas phase. In addition, positive ion f.a.b . mass spectrometry was found to be useful for the analysis of a series of protected O-( diorganylphosphono ) seryl-containing dipeptides and tripeptides ( organyl = Ph, Et, Me, Bzl ). The obtained spectra showed that β-elimination fragmentation of the Ser(PO3R2) residue was more pronounced with the tripeptide series and indicated that there was increased sensitivity of the O-( diorganylphosphono ) seryl residue with replacement of the Boc group by an amino acyl residue at its N-terminus.

Ligand Exchange in FAB Mass Spectrometry of Monomerie and Dimeric Corrinoids

1984 ◽  
Vol 39 (11) ◽  
pp. 1548-1552 ◽  
Author(s):  
Lutz Grotjahn ◽  
Ludger Ernst
Keyword(s):  
Mass Spectrometry ◽  
Ligand Exchange ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Molecular Ions ◽  
Negative Ion ◽  
Fab Mass Spectrometry ◽  
Fab Mass Spectra

Abstract In the Fast Atom Bombardment (FAB) mass spectra of monomeric and dimeric corrinoids, exchange of metal-bound ligands against matrix particles is observed which leads to pseudo molecular ions. Negative ion FAB mass spectra in particular, give distinct information on the intact molecular units.

Fast Atom Bombardment Mass Spectrometry of the Vitamin B12 Analogues Hydrogenobalamin and Cupribalamin

1984 ◽  
Vol 39 (2) ◽  
pp. 248-251 ◽  
Author(s):  
Lutz Grotjahn ◽  
Volker B. Koppenhagen ◽  
Ludger Ernst
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrum ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Metal Clusters ◽  
Cobalt Atom ◽  
Vitamin B ◽  
Metal Free ◽  
Characteristic Fragment ◽  
Fab Mass Spectra

Hydrogenobalam in (metal-free vitamin B12) and cupribalamin are characterized by their fast atom bombardment (FAB) mass spectra which show molecular ion and characteristic fragment ion peaks. These spectra and the high-resolution FAB mass spectrum of cobalamin (vitamin B12) show that the (M+H)+-CN-59 peak for the latter is due to loss of acetamide and not of the central cobalt atom. In the FAB mass spectrum of cupribalamin metal clusters are observed

Identification of Aflatoxins by Quadrupole Mass Spectrometry/Mass Spectrometry

1984 ◽  
Vol 67 (4) ◽  
pp. 734-738 ◽  
Author(s):  
Ronald D Plattner ◽  
Glenn A Bennett ◽  
Robert D Stubblefield
Keyword(s):  
Mass Spectrometry ◽  
Aflatoxin B1 ◽  
Impact Ionization ◽  
Negative Ion ◽  
Quadrupole Mass ◽  
Molecular Anion ◽  
Negative Ion Mode ◽  
Protonated Molecules ◽  
Positive Ion ◽  
Mass Spectrometry Mass Spectrometry

Abstract MS/MS daughter experiments were recorded for aflatoxins B1, B2, G1, G2, M1, M2, and aflatoxicol, using 3 ionization modes. Daughters were recorded from the molecular ion (M+) using electron impact ionization (EI). Daughters from the protonated molecules (MH+) were recorded in the positive ion mode and the daughters from the molecular anion (M+) were recorded in the negative ion mode using chemical ionization (CI). These daughter spectra are all relatively simple. The EI daughters are quite similar to conventional EI spectra. The yield of (M-) is about 100 times greater than the yield of M+ in EI or MH+ in isobutane CI spectrum. Negative ion daughter spectra were used to demonstrate the feasibility of determining the presence of aflatoxin B1 in crude extracts of contaminated corn. Aflatoxin B1 could be detected at 10 ppb.

The fast atom bombardment mass spectra of some N-substituted pyrimidinium salts

1987 ◽  
Vol 65 (4) ◽  
pp. 718-721 ◽  
Author(s):  
Clement W. Kazakoff ◽  
Robin T. B. Rye ◽  
Oswald S. Tee
Keyword(s):  
Concentration Dependence ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Negative Ion ◽  
Cluster Ions ◽  
Solution Equilibria ◽  
Mixed Cluster ◽  
Cluster Ion ◽  
Conventional Solution ◽  
Positive Ion

The fast atom bombardment mass spectra of selected 1,2-dihydro-1,3-disubstituted-2-oxo-pyrimidinium salts are presented. Loss of N-substituents from the solute cation is the principal fragmentation observed in the positive ion spectra. Several concentration dependent features of the spectra are identified; these are thought to result from the interaction of the solute cation with bombardment-induced matrix fragments. Cluster ions are observed in both positive and negative ion spectra. In a mixed solute system cluster ions resulting from extensive cation and anion mixing are observed; the concentration dependence of these mixed cluster ion peaks can be approximately described in terms of conventional solution equilibria.

Phospholipid analogue profiles of Peptostreptococcus, Micromonas, and Finegoldia species analysed by fast atom bombardment mass spectrometry

2001 ◽  
Vol 47 (1) ◽  
pp. 96-101 ◽  
Author(s):  
C E Radcliffe ◽  
D B Drucker ◽  
V Boote ◽  
G Fletcher-Williams ◽  
M A Claydon
Keyword(s):  
Mass Spectrometry ◽  
Fast Atom Bombardment ◽  
Soft Tissues ◽  
Anaerobic Growth ◽  
Negative Ion ◽  
Mucous Membranes ◽  
Negative Ion Mode ◽  
Staphylococcus Spp ◽  
Chloroform Methanol ◽  
Lactobacillus Spp

Species of Peptostreptococcus cause a variety of infections, primarily abscesses of soft tissues, joints, and mucous membranes. The aim of this study was to compare the phospholipid analogue profiles of Peptostreptococcus species, represented by P. anaerobius, P. asaccharolyticus, P. indolicus, P. lacrimalis, and P. prevotii; Micromonas micros (P. micros) and Finegoldia magna (P. magnus). After anaerobic growth on blood-FAA, lipids extracted by chloroform-methanol (2:1 v/v) were purified, then analysed by fast atom bombardment mass spectrometry (FAB-MS) in negative ion mode. The major peaks with mass to charge (m/z) 719, 721, and 749, corresponded to phosphatidylglycerol analogues, namely PG (32:1), PG (32:0), and PG (34:0), which have been found previously in Lactobacillus spp., Clostridium difficile, and Staphylococcus spp. Other major peaks observed, with m/z 619, 647, 665, 675, 677, 687, 691, 693, 701, 703, 707, 733, and 746 have also been reported in one or more of these three species. However, other major peaks found here in Peptostreptococcus, Micromonas, and Finegoldia have not been described elsewhere; these are 501, 514, 515, 618, 659, 673, 676, 688, 690, 692, 694, 700, 706, 715, 718, 722, and 750. We conclude that Peptostreptococcus, Micromonas, and Finegoldia isolates are chemically unique.Key words: Peptostreptococcus, Micromonas, Finegoldia, phospholipids, FAB-MS.

A comparison of the electron impact and fast atom bombardment mass spectra of some group IV organometallic halides

1985 ◽  
Vol 63 (8) ◽  
pp. 2308-2312 ◽  
Author(s):  
Jack M. Miller ◽  
Adrian Fulcher
Keyword(s):  
Electron Impact ◽  
Condensed Phase ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Group Iv ◽  
Major Exception ◽  
Positive Ion ◽  
Fab Mass Spectra ◽  
Primary Ionization

The positive ion fast atom bombardment (FAB) mass spectra of a series of group IV organometallic halides, (phenyl)3MCl (M = Ge, Sn, Pb), (phenyl)3PbX (X = Cl, Br, I) and Sn(phenyl)nCl4−n are reported in a sulfolane matrix, and compared to their corresponding EI spectra. The use of other matrix liquids such as glycerol thioglycerol, diamylphenol, 18-crown-6/tetraglyme, and p-nitrophenyloctylether are discussed. Disappointingly FAB, like EI, does not produce significant parent ions for group IV organometallics. The FAB and EI spectra are remarkably similar with one major exception. In EI, the loss of a phenyl is preferred over the loss of a halide, while in FAB the reverse is the case, strongly suggesting that the primary ionization occurs in the condensed phase.

Pregnanediol-3 alpha-glucuronide measured in diluted urine by mass spectrometry with fast atom bombardment/negative-ion ionization.

1985 ◽  
Vol 31 (1) ◽  
pp. 46-49 ◽  
Author(s):  
G Moneti ◽  
G Agati ◽  
M G Giovannini ◽  
M Pazzagli ◽  
R Salerno ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Fast Atom Bombardment ◽  
Internal Standard ◽  
Mass Spectrometric ◽  
Negative Ion ◽  
Spectrometric Method ◽  
Mass Spectrometric Method ◽  
Ionization Technique ◽  
Fast Atom Bombardment Ionization ◽  
Negative Ion Mode

Abstract We describe a mass-spectrometric method based on the fast atom bombardment ionization technique in the negative-ion mode for measuring pregnanediol-3 alpha-glucuronide in diluted urine from women. The procedure requires addition of testosterone-17 beta-D-glucuronide (2.5 micrograms/25 microL) to the urine sample as internal standard, and the sample is added directly to the fast atom bombardment target with no further manipulation. We have assessed and evaluated the method by the traditional criteria of reliability.

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