SOAT <i>O</i>-acetylates GD1b in the C-9 position of the alpha-2,8 bound sialic acid.

<p>(<b>A</b>) Comparison of the 700 MHz <sup>1</sup>H-NMR spectra of <b>GD1b</b> and <b>AcGD1b</b> in DMSO-d<sub>6</sub>/D<sub>2</sub>O 98∶2 at 298 and 295 K, respectively. (B) Magnified <sup>1</sup>H-NMR spectra in the anomeric and acetyl region of <b>GD1b</b> and <b>AcGD1b</b>. (C) Comparison of the anomeric region in the 2D <sup>1</sup>H-<sup>13</sup>C multiplicity-edited HSQC spectra of <b>GD1b</b> and <b>AcGD1b</b>. In this spectrum signals arising from CH<sub>3</sub> and CH groups have different sign (positive) to those of CH<sub>2</sub> groups (negative). Cross peaks are positive (several contours) for CH<sub>2</sub> groups and negative (one contour) for CH and CH<sub>3</sub> groups. In both cases the corresponding 1D <sup>1</sup>H specrum is shown above the 2D spectrum.</p>