Polyvalent carbohydrate molecules

A method for the preparation of polyvalent carbohydrate molecules which comprise:

• a) reacting, as a first reactant, at least one carbohydrate having at least one monosaccharide unit with a second reactant, which is a partially protected starch having at least one free hydroxyl group per two consecutive monosaccharide units of the starch, to form a linkage between free hydroxyl groups of the partially protected starch and the anomeric carbon of the carbohydrate, and reacting the first reactant to form the linkage between the hydroxyl groups of the starch molecule and the anomeric carbon of the carbohydrate, which is through a tether obtained by
• i) forming a glycosylating agent from at least one carbohydrate molecule or a library of carbohydrates molecules equipped with a suitable activated leaving group at the anomeric carbon of the carbohydrate or library of carbohydrate molecules;
• ii) subjecting the glycosylating agent to a reaction with a non-geminal hydroxyhalogenoalkane which yields a tethered first reactant which comprises a glycoside of a halogenoalkane;
• and
• iii) subjecting the glycoside of the halogenoalkane to a condensation reaction with a starch or partially protected starch, under strong basic conditions, in which reaction, ether linkages between the linker bound to the glycosylating agent and the starch are formed, which linkages as well as the glycosidic bond cannot be severed during subsequent manipulations;
• b) removing all of the protecting groups;
• c) purifying the polyvalent carbohydrate molecules;
• and optionally
• d) subjecting such polyvalent carbohydrate molecules to additional glycosylations.