Portal de Periódicos da CAPES

Stability of N-acyl groups in methylated α2 → 8-linked oligosialosyl chains toward methanolysis. Analysis by chemical ionization-mass spectrometry

1982; Elsevier BV; Volume: 125; Issue: 1 Linguagem: Inglês

10.1016/0003-2697(82)90391-8

1096-0309

Sadako Inoue, Go Matsumura, Yasuo Inoue,

Enzyme Structure and Function

Abstract The stability of N-acetyl group of methylated trisaccharide of N-acetylneuraminic acid toward methanolysis under conditions used in methylation analysis was investigated. The analysis of the products obtained after a reaction sequence, methylation-methanolysis-deuterioacetylation, by chemical ionization-mass spectrometry has led to unequivocal conclusion that N-acetyl group of internal 8-O-substituted residue of the methylated oligosialosyl compound is de-N-acetylated under conditions sufficient to cleave glycosidic linkages, whereas the fully methylated nonreducing terminal residue of neuraminic acid is completely resistant to de-N-acetylation. The reaction mechanism to explain these observations is presented.