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

(A) Comparison of the 700 MHz ¹H-NMR spectra of GD1b and AcGD1b in DMSO-d₆/D₂O 98∶2 at 298 and 295 K, respectively. (B) Magnified ¹H-NMR spectra in the anomeric and acetyl region of GD1b and AcGD1b. (C) Comparison of the anomeric region in the 2D ¹H-¹³C multiplicity-edited HSQC spectra of GD1b and AcGD1b. In this spectrum signals arising from CH₃ and CH groups have different sign (positive) to those of CH₂ groups (negative). Cross peaks are positive (several contours) for CH₂ groups and negative (one contour) for CH and CH₃ groups. In both cases the corresponding 1D ¹H specrum is shown above the 2D spectrum.