Differentiation of diastereomeric conduramine derivatives under electron ionization and chemical ionization mass spectral conditions.
Rapid Commun Mass Spectrom
; 21(4): 579-88, 2007.
Article
en En
| MEDLINE
| ID: mdl-17262898
ABSTRACT
Diastereomeric conduramine derivatives, i.e., (1R,2S,3R/S,6S)-6-(N-carbomethoxyamino) 1,2-O-isopropylidenecyclohex-4-ene-1,2,3-triol (1 and 2) and their O-acetyl derivatives (3 and 4), were studied using gas chromatography (GC) with electron ionization (EI) and chemical ionization (CI). The EI mass spectra of diastereomeric pairs show consistent differences in the relative abundances of characteristic ions. The EI fragmentation patterns are based on precursor/product ion spectra, high-resolution mass spectrometry (HRMS) and deuterium labelling. The CI spectra show differences from the EI spectra, and the isobutane/CI spectra are much simpler than the methane/CI spectra. The differences shown in the CI spectra are similar to those shown in the product ion spectra of [M+H](+) ions generated under electrospray ionization (ESI) conditions. Theoretical calculations are performed to understand the observed differences. The differences in the relative stabilities of molecular ions, or protonated molecules at different sites, can explain the observed differences in the spectra.
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Base de datos:
MEDLINE
Asunto principal:
Ciclohexanoles
/
Ciclohexilaminas
/
Espectrometría de Masa por Ionización de Electrospray
/
Cromatografía de Gases y Espectrometría de Masas
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Rapid Commun Mass Spectrom
Año:
2007
Tipo del documento:
Article
País de afiliación:
India