590725 Disclosed is a method of preparing sulphated glycan molecules involving at least two sulfation steps. For example sulphating xylan to xylan sulphate then hydrolysising to hydrolysed xylan sulfates and further performing a sulfation of the hydrolysed sulfate. Preferably the molecules comprise (a) one or more linear 1-4 conjugated beta-D-xylose units； and (b) at least one 4-O-methyl-[beta]-D-glucuronic acid unit attached to carbon-2 of every about eight to ten (on average) said xylose units.
