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Mass spectrometry of the positionally isomeric, monobenzyl ethers of methyl glycopyranosides

✍ Scribed by Vincent Mihálov; Vladimír Kováčik; Rudolf Toman; Igor Tvaroška


Publisher
Elsevier Science
Year
1983
Tongue
English
Weight
600 KB
Volume
119
Category
Article
ISSN
0008-6215

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✦ Synopsis


The electron-impact, mass-spectrometric behavior of all theoretically possible, positionally isomeric monobenzyl ethers of methyl pento-, hexo-, and 6-deoxyhexo-pyranosides is described, on the basis of 70-and 12-eV mass spectra, Odcuterium-labeling experiments, elemental composition, and metastable-transition measurements.

The semiempirical MNDO quantum-chemical method was used for calculation of both the geometrical parameters (bond lengths, bond angles. and dihedral angles) and the distribution of net charges in the cyclic and acyclic forms of the abundant

[C1H703]+ and [CsH90J] + ions. The results obtained show that the cyclic structures of both ions are the more stable. Differences in the fragmentation of the compounds studied have been applied for establishing criteria that permit simple and unambiguous localization of the benzyl group in monobenzyl ethers of methyl glycopyranosides.


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