Synthetic vaccines against

1. A saccharide of general formula (I):

wherein A represents —(CH 2 ) o1 —;

o1 represents an integer selected from 1, 2, 3, 4, 5 and 6;

M, N and P represent independently of each other one of the following sugar fragments:

wherein the sugar fragments S1, S2, S3 are connected to each other and to —O-A-SH fragment via O-glycosidic bonds, each sugar fragment S1, S2, and S3 is not more than once present in the general formula (I), sugar fragment Si cannot be simultaneously connected to —O-A-SH and sugar fragment S3, sugar fragment S3 cannot be simultaneously connected to —O-A-SH and sugar fragment S2, and sugar fragment S2 cannot be simultaneously connected to —O-A-SH and sugar fragment S1, and n1, n2 and n3 are integers selected from 0 and 1, wherein at least one of the integers n1, n2 and n3 is 1

and pharmaceutically acceptable salts of these saccharides.

2. A synthesis of the saccharide of the general formula (I):

wherein A represents (CH 2 ) o1;

o1 represents an integer selected from 1, 2, 3, 4, 5 and 6;

M, N and P represent independently of each other one of the following sugar fragments:

wherein the sugar fragments S1, S2, S3 are connected to each other and to —O-A-SH fragment via O-glycosidic bonds, each sugar fragment S1, S2, and S3 is not more than once present in the general formula (I), sugar fragment Si cannot be simultaneously connected to —O-A-SH and sugar fragment S3, sugar fragment S3 cannot be simultaneously connected to —O-A-SH and sugar fragment S2, and sugar fragment S2cannot be simultaneously connected to —O-A-SH and sugar fragment S1, and n1, n2 and n3 are integers selected from 0 and 1, wherein at least one of the integers n1, n2 and n3 is 1

and comprising :

A1) Reacting the compound 2 of the formula:

wherein P 1 -P 3 represent protecting groups,

with the compound 3 of the formula

wherein P 4 represents a protecting group, in order to obtain compound 4 of general formula:

wherein P 1 -P 4 and A are defined as above;

and

performing removal of protecting groups P 1 -P 4 on compound 4 to afford monosaccharide disulfide 5 of general formula:

wherein A is defined as above, and wherein monosaccharide disulfide 5 is further treated with a reducing agent to afford monosaccharide 6 of general formula:

wherein A is defined as above;

or

performing selective deprotection on compound 4 to afford compound 7 of general formula

wherein P 5 is a protecting group and P 1 , P 3 , P 4 and A are defined as above;

or

A2) Reacting compound 8 of general formula

wherein P 6 and P 7 represent protecting groups, with compound 3 to afford compound 9 of general formula

wherein P 6 , P 7 and A are defined as above;

and

performing conversion of the azido group to acetamido group and removal of the protecting groups P 4 , P 6 and P 7 on compound 9 to afford monosaccharide disulfide 10 of general formula:

wherein A is defined as above, and wherein monosaccharide disulfide 10 is further treated with a reducing agent to afford monosaccharide 11 of general formula:

wherein A is defined as above;

or

performing selective deprotection on compound 9 to afford compound 12 of general formula:

wherein P 4 , P 7 and A are defined as above;

or

A3) Reacting compound 13 of general formula

wherein P 8 -P 11 represent protecting groups, with compound 3 to afford compound 14 of general formula:

wherein P 4 , P 8 -P 11 are defined as above; and

performing selective deprotection of compound 14 to afford compound 15 of general formula:

wherein P 4 , P 8 , P 9 , P 11 and A are defined as above; and

B1) Reacting compound 7 with compound 13 to afford compound 16 of general formula:

wherein P 1 , P 3 -P 5 , P 8 -P 11 and A are defined as above; and

performing removal of protecting groups P 1 P 3 -P 5 , P 8 -P 11 on compound 16 to afford disaccharide disulfide 17 of general formula:

wherein A is defined as above and wherein disaccharide disulfide 17 is further treated with a reducing agent to afford disaccharide 18 of general formula:

wherein A is defined as above;

or

performing selective removal of protecting group P 10 on compound 16 to afford compound 19of general formula:

wherein P 1 , P 3 -P 5 , P 8 , P 9 , P 11 and A are defined as above; or

B2) Reacting compound 15 with compound 8 to afford compound 20 of general formula:

wherein P 4 , P 6 -P 9 , P 11 and A are defined as above; and

performing conversion of the azido group to acetamido group and removal of the protecting groups P 4 , P 6 -P 9 , P 11 on compound 20 to afford disaccharide disulfide 21 of general formula:

wherein A is defined as above and wherein disaccharide disulfide 21 is treated with a reducing agent to afford disaccharide 22 of general formula:

wherein A is defined as above;

or

performing selective removal of protecting group P 6 on compound 20 to afford compound 23of general formula:

wherein P 4 , P 7 -P 9 , P 11 and A are defined as above;

or

B3) Reacting compound 12 with compound 2 to afford compound 24 of general formula:

wherein P 1 -P 4 , P 7 and A are defined as above,

and

performing conversion of the azido group to acetamido group and removal of protecting groups P 1 -P 4 and P 7 on compound 24 to afford disaccharide disulfide 25 of general formula:

wherein A is defined as above, and wherein disaccharide disulfide 25 is further treated with a reducing agent to afford disaccharide 26 of general formula:

wherein A is defined as above;

or

performing selective deprotection on compound 24 to afford compound 27 of general formula:

wherein P 12 is a protecting group and P 1 , P 3 , P 4 , P 7 and A are defined as above;

and

C1) Reacting compound 19 with compound 8 to afford compound 28 of general formula:

wherein P 1 , P 3 -P 9 , P 11 and A are defined as above;

and

wherein protecting group P 6 is replaced with protecting group P 13 in order to obtain compound 29 of the following chemical formula:

wherein P 1 , P 3 -P 5 , P 7 -P 9 , P 11 , P 13 and A are defined as above;

and

conversion of compound 29 to trisaccharide disulfide 30 by conversion of the azido group in the acetamido group and cleavage of the protecting group P 1 , P 3 -P 5 , P 7 -P 9 , P 11 , 13 , wherein compound 30 is of general formula:

and wherein A is defined as above;

and

conversion of trisaccharide disulfide 30 to trisaccharide 31 by treatment with a reducing agent, wherein compound 31 is of general formula:

and wherein A is defined as above;

or

C2) Reacting compound 23 with compound 2 to afford compound 32 of general formula:

wherein P 1 -P 4 , P 7 -P 9 , P 11 and A are defined as above;

and

conversion of compound 32 to trisaccharide disulfide 33 by conversion of the azido group in the acetamido group and cleavage of the protecting group P 1 -P 4 , P 7 -P 9 , P 11 , wherein compound 33 is of general formula:

wherein A is defined as above;

and

conversion of trisaccharide disulfide 33 to trisaccharide 34 by treatment with a reducing agent, wherein compound 34 is of general formula:

wherein A is defined as above;

or

C3) Reacting compound 27 with compound 13 to afford compound 35 of general formula:

wherein P 1 , P 3 , P 4 , P 7 -P 11 and A are defined as above;

and

conversion of compound 35 to trisaccharide disulfide 36 by conversion of the azido group in the acetamido group and cleavage of the protecting group P 1 , P 3 , P 4 , P 7 -P 11 wherein compound 36 is of general formula:

wherein A is defined as above;

and

conversion of trisaccharide disulfide 36 to trisaccharide 37 by treatment with a reducing agent, wherein compound 37 is of general formula:

wherein A is defined as above.

3. The synthesis according to claim 2 further comprising:

preparing a salt of the compound of general formula (I) or preparing a lyophilisate of the compound of general formula (I) or of the salt of the compound of general formula (I).

4. The synthesis according to claim 2 , wherein the reactions between compounds 2 and 3, compounds 2 and 12, and compounds 2 and 23 are performed in presence of DMTST and TTBPy in a mixture of non-polar and polar aprotic solvents.

5. The synthesis according to claim 2 , wherein the replacement of protecting group P 6 on compound 28 with protecting group P 13 to obtain compound 29 is performed in two steps, first involving the reaction of compound 28 with hydrazine or a hydrazinium salt in a solvent or a mixture of solvents, and second by treatment of the product obtained after the first step with BnOCH 2 SCy, DMTST and TTBPy in a non-polar solvent.

6. The synthesis according to claim 2 , wherein the cleavage of the protecting groups involves first cleavage of the base-labile protecting groups by treatment with a base in a mixture of polar aprotic and polar protic solvents; and second cleavage of the protecting groups sensitive to hydrogenation by exposure to sodium and ammonia in a mixture of polar protic and polar aprotic solvents.

7. A pharmaceutical composition comprising the saccharide according to claim 1 together with at least one pharmaceutically acceptable cryoprotectant, lyoprotectant, excipient and/or diluent.