83552-81-2Relevant articles and documents
Unexpected Structural Integrity of Gas Phase Isoquinoline Cations that Eliminate HCN
Baldwin, Michael A.,Gilmore, Jeremy,Mruzek, Margaret N.
, p. 127 - 129 (1983)
13C labellining has been used to study isoquinoline molecular ions undergoing breakdown by HCN elimination in a mass spectrometer.For otherwise stable ions caused to fragment by collisional activation, there is no skeletal rearrangement prior to HCN loss.Of the ions formed by 70 eV electron impact, 69percent of those which fragment in the ion source by HCN loss retain their structural integrity, as do 44percent of the metastable ions.Of the ions that eliminate HCN without prior arrangement, approximately two-thirds eliminate C-1 and one-third eliminate C-3.Critical energies are reported for the elimination of HCN from pyridine and isoquinoline molecular ions.
ISOTOPICALLY ENRICHED PYRIMIDIN-5-YL ACETIC ACID DERIVATIVES AS CRTH2 ANTAGONISTS
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Page/Page column 21, (2011/08/03)
Provided herein are 2H- and 13C-enriched compounds of formula (I) or (II); wherein R is as defined herein, and wherein at least one hydrogen atom, in certain embodiments, three or more hydrogen atoms, are deuterium atoms or at least one carbon atom is a carbon-13 atom. Also provided are pharmaceutical compositions and methods using the 2H- and 13C-enriched compounds, useful for treating CRTH2-related diseases or disorders such as, for example, asthma, allergic rhinitis, atopic dermatitis, allergic conjuvatitis, Churg-Strauss syndrome, sinusitis, basophilic leukemia, chronic urticaria or basophilic leukocytosis.
The synthesis of alkyl aryl nitriles from N-(1-arylalkylidene)-cyanomethylamines. Part 2. Mechanism
Perosa, Alvise,Selva, Maurizio,Tundo, Pietro
, p. 1033 - 1037 (2007/10/03)
The mechanism of the rearrangement of N-(1-arylalkylidene)cyanomethylamines ArC(=NCH2CN)R 1 to the corresponding nitriles ArCH(CN)R2 (in DMF, at 150°C, with K2CO3) is described. Reaction 1 → 2 was investigated for different types of imine 1, and it was found that with a leaving group other than CN- the reaction does not proceed to yield the nitrile, whereas imines such as PhC(=NCH2CN)H, prepared starting from aldehydes rather than ketones, yield the expected phenylacetonitrile even at temperatures as low as 120°C. Evidence for the mechanism comes from a study of the reactivity of the postulated intermediates: 2-cyano-3-phenylaziridine 4c, and 2,2-diphenyl-2H-azirine 5b. The route involving aziridine 4c is ruled out, since this compound does not react at all under the investigated conditions. The 2H-azirine 5b instead, yields the corresponding diphenylacetonitrile in DMF with K2CO3, at 150°C. The transformation seems to involve an initial deprotonation, followed by an intramolecular ring closure-CN elimination step, which yields the 2H-azirine. The azirine then isomerizes to the nitrile. Additional evidence for the intermediacy of the 2H-azirine, based on 1H NMR monitoring of the reaction 1 → 2, is described. Finally, the results of a simple isotope exchange experiment provide a rationale for the previously observed scrambling of labels, and further confirm the proposed mechanism.
