Patent ID: 6951934

Claim:
A method of preparing functionalized β-(1,3)-glucans comprising a reaction between a glycosyl donor and a glycosyl acceptor, wherein the glycosyl donor is selected from the group consisting of the compounds of formulae Ia and Ib: in which: X is a leaving group selected from the group consisting of: a group of formula S(O) p R a , in which R a is selected from the group consisting of an alkyl radical having 1 to 18 carbon atoms, 1,1-dicyclohexymethyl, an aryl radical which is non-substituted or substituted by an alkyl or alkoxy group having 1 to 6 carbon atoms, a nitro and an acetamide group, and p is an integer equal to 0 or 1; R 1 is selected from the group consisting of: an alkyl, haloalkyl or ketoalkyl radical having 1 to 6 carbon atoms; an aryl radical which is non-substituted or substituted with one or more groups selected from the group consisting of a halogen atom, an alkoxy radical having 1 to 6 carbon atoms and a nitro group; R 3 and R 4 , which are different from —CO—R 1 and from R 2 , independently represent a benzyl, chlorobenzyl, methoxybenzyl, nitrobenzyl, allyl, methylnaphthyl, chloroacetyl, trialkylsilyl or triarylmethyl radical; or together form an ethylidyl, isopropylidyl, hexafluoroisopropylidyl, cyclopentylidyl, cyclohexylidyl, cycloheptylidyl, butylidyl, 1-tert-butylethylidyl, benzylidyl, methoxybenzylidyl or 1-phenylbenzylidyl radical; R 2 is a methylnaphthyl radical; n is an integer of between 1 and 4; it being specified that in the case in which n is greater than 1, it is possible for —COR 1 , R 3 and R 4 to be different from one glycosyl unit to another; and wherein the glycosyl acceptor selected from the group consisting of the compounds of formula II: in which: Y is: a group of formula —O—R b in which R b is an alkyl radical having 1 to 24 carbon atoms, an alkenyl radical having 2 to 24 carbon atoms or an arylalkylaryl or arylalkyl radical having 6 to 18 carbon atoms; a serine or threonine; a sterol; a glycerolipid; a group of formula —S—R a in which R a is as defined above; R 1 , R 3 and R 4 are as defined above and; m is an integer of between 1 and 8, it being specified that in the case in which m is greater than 1, it is possible for —COR 1 , R 3 and R 1 to be different from one glycosyl unit to another, wherein said reaction is carried out in solution in an anhydrous organic solvent, at a temperature between −80° C. and 40° C., for a period of 1 minute to 8 hours, in the presence of a promoter.