Cell-surface carbohydrates and their interactions. I. NMR or N-acetyl neuraminic acid.

1. The proton nuclear magnetic resonance spectrum of the sialic acid N-acetyl neuraminic acid was measured and completely assigned. The coupling constants for interactions between protons are obtained and the assignments checked by calculating the observed line intensities. 2. It was verified that the pyranose ring exists in the 1C (1-C4) conformation as the alph-D anomer and no mutarotation was detectable. Coupling constants for the glycerol side chain were interpreted to yield its most likely conformation.