ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Mass spectrometry of uronic acid derivatives. X. Identification of methyl (methyl O-methylhexopyranosid)uronates by mass spectrometry

V. Kováčik, V. Mihalov, and P. Kováč

Institute of Chemistry, Slovak Academy of Sciences, 809 33 Bratislava

Abstract:  Based on mass spectral fragmentation of methyl (methyl O-methyl-α-D-gluco- and galactopyranosid)uronates a simple procedure is proposed for the determination of the number and location of methyl groups in methyl (methyl 0-methylhexopyranosid)uronates, the products of methanolysis of methylated acidic polysaccharides and other uronic acid-containing substances. The advantage of the use of low-energy electrons (12 eV) for this purpose is demonstrated. The comparison of the 12 eV mass spectra of gluco and galacto derivatives provided data from which criteria were deduced enabling, except for the fully methylated derivatives, to distinguish between these two diastereoisomeric forms. The most significant factor for the stereochemical assign­ment is the presence or absence of the molecular, m/e 169 and m/e 155 ion peaks in the spectra.

Full paper in Portable Document Format: 322a258.pdf

Chemical Papers 32 (2) 258–266 (1978)