Structural studies on 2-acetamido-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine and 2-acetamido-6-O-(alpha-L-fucopyranosyl)-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine by 360-MHz proton-magnetic-resonance spectroscopy.

The 360-MHz proton magnetic resonance spectra of 2-acetamido-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine (GlcNAcbeta1 leads to Asn) and 2-acetamido-6-O-(alpha-L-fucopyranosyl)-1-N-(4-L-aspartyl)-2-deoxy-beta-D-glucopyranosylamine (Fucalpha1 leads to 6GlcNAcbeta1 leads to Asn) in deuterium oxide were completely interpreted. The chemical shifts and coupling constants were refined by simulation of the spectra. By means of an adapted Karplus equation the pyranose ring conformation of the sugars was calculated. The change of the geminal coupling constant J6a,6b in the N-acetylglucosamine residue of Fucalpha1 leads to 6GlcNAcbeta1 leads to Asn with respect to GlcNAcbeta1 leads to Asn is proposed to be characteristic for the (1 leads to 6) glycosidic linkage.