... displacements of parts of the signals for C1 and C3 of Rha4NAcIIfrom d 102.9 and78.0 t o d 101.6 a nd 76.6, respectively, which a re typical of b-effe cts of acetylation at O2 [22]. Therefore, part of ... and1H,13CHMQC spectra of PSNH4OHand PS enabled the determi-nation of the site of attachment of t he O-acetyl group. Inthe1H,13C HMQC s pectrum, the intensity of the H2/C2Fig. 1. 125-MHz13C-NMR ... (1998)Structure of the O-speci®c polysaccharide of CitrobacterO3a,1b,1c. Carbohydr. Res. 306 , 331±333.8. Knirel, Y.A. & Kochetkov, N.K. (1994) The structure of lipo- polysaccharides of Gram-negative...