Abstract:It appears that negative ion mass spectra measured with a commercial instrument and the electron energies used (20-70 ev) are not suitable either for molecular weight or for structure determination . . .". Dies war die SchluBfolgerung einer 1965 veroffentlichten Untersuchung['] und die damals fast einhellige Meinung zur Bedeutung von Massenspektren negativer Ionen fur die Strukturanalyse organischer Verbindungen. DaB Chinone und Nitroarene Ausnahmen von dieser Regel bildeten, wurde eher als Bestatigung angese… Show more
“…l a , 212, and 3a. There is no doubt that the species we have isolated have the assigned atomic composition. Since the precursors to the radical anions are well characterized, and since rearrangement processes in radical anions are of minor importance [18], we are confident that these signals arise from the radical anions of nitrosocarbonyl compounds la+. Moreover, in a preliminary communication [ 191, we have presented the CR-MS and NR-MS of nitrosoformaldehyde (la) and its isomer, nitrocarbene.…”
Section: Characterization Of Nitrosocarbonyl Compounds Bymentioning
~~The neutral molecules nitrosoformaldehyde (la), 1-nitrosoacetaldehyde (Ib), and 2,2,2-trifluoro-1-n1troso-acetaldehyde (lc) have been generated and detected by neutralization-reionization mass spectrometry (NR-MS)
“…l a , 212, and 3a. There is no doubt that the species we have isolated have the assigned atomic composition. Since the precursors to the radical anions are well characterized, and since rearrangement processes in radical anions are of minor importance [18], we are confident that these signals arise from the radical anions of nitrosocarbonyl compounds la+. Moreover, in a preliminary communication [ 191, we have presented the CR-MS and NR-MS of nitrosoformaldehyde (la) and its isomer, nitrocarbene.…”
Section: Characterization Of Nitrosocarbonyl Compounds Bymentioning
~~The neutral molecules nitrosoformaldehyde (la), 1-nitrosoacetaldehyde (Ib), and 2,2,2-trifluoro-1-n1troso-acetaldehyde (lc) have been generated and detected by neutralization-reionization mass spectrometry (NR-MS)
“…In st/indig zunehmendem MaBe wird zum Nachweis von Arzneistoffen (und deren Metaboliten), Rauschgiften und anderen Xenobiotica im biologischen Material die Massenspektrometrie in Kombination mit der Gaschromatographie und einem Datensystem eingesetzt; dies gilt insbesondere seit der EinfiJhrung neuer MeBmethoden (,,negative ions"; DCI; FAB) und CI-Reaktandgase wie A m m o n i a k [1][2][3][4][5][6][7][8][9].…”
After oral application of pentacozine (Fortral) besides the unchanged drug some further excretion products were detected by glc/ms in human urine. For their identification e.i.-and c.i.-mass-spectrometry as well as the just recently available FAB-technique were employed. All analyses were performed on a VG-Micromass 7035; the samples were introduced in the ion source via a fused silica, bonded phase capillary column (30 metres; DB-1 J + W, Inc.). The analytical profiles of the pure substance and some metabolites are reported as well as the behaviour of the pure substance on acidic hydrolyzation.
“…This is in contrast to our observation as well as to those of other i . See Ref 1 (1) (2) laboratories where under CI conditions no negative ions could be detected in the CH, plasma (source pressure between 0.01 and 1 Torr; negative ions occur only at low pressures6).…”
mentioning
confidence: 99%
“…[2M -HI-), or by reactions of a substrate molecule with impurities (e.g. H20, 0,) present in the ion source3 (1) The formation of [M+14]-' from Ni and of [M+15]-from Co chelates of Schiff bases (CH, and iso-C4H10) has been explained by reaction of [MI-' with the neutral reactant gas (Eqns (1) and (2)) and formation of metal-carbon bonds rather than attack of the ligand (to account for the differing behaviour of different metals). The source of the C, units has been established by parallel experiments with CD,.,…”
mentioning
confidence: 99%
“…[M]-'+CH,(~SO-C,H,~) 3 [M+CH,]-+H'('C,H,) (2) The formation of [M+ 151-and [M+29]-from dithiolate and porphyrin complexes of various metals (CH,) is assumed to occur via Eqn (2); however, alkylation of the ligand is suggested since [ligand+ CH3]-ions have been observed. '…”
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