Disaccharides having units with a glucosamine and with a uronic-acid structure, their preparation and their biological application

Claim 2

1,4 a disaccharides formed from units with a D-glucosamine and glucuronic acid structure, characterised in that they correspond to the formula (I): in which: -Z represents an azide group or a group comprising an amino function, obtainable according to the usual reactions of organic chemistry, from the azido group, ― M represents a hydrogen atom or a ―SO 3 M 1 group in which M 1 represents an organic or inorganic cation, and, in the latter case, in particular an alkali metal, or represents an acetyl group; - R represents an alkyl radical of 1 to 4 carbon atoms, in particular, a methyl radical or again aryl, and - R 1 represents a hydrogen atom, an alkyl radical comprising from 1 to 4 carbon atoms, in particular, a methyl radical, or a metal, in particular, an alkali metal.

Claim 3

Disaccharides according to claim 1 wherein Z represents a group of the structure ―NHB in which B represents a hydrogen atom or an acetyl group or a sulphate group possibly in the form of a salt with an organic or inorganic cation, and in the latter case, in particular an alkali cation.

Claim 4

Disaccharides according to claim 1, characterised in that they correspond to the formula II: or to the formula III: in which, B, R, R 1 have the above-indicated meanings, M 1 representing advantageously an alkali metal, in particular, sodium.

Claim 5

Disaccharides according to claim 3, wherein B represents an acetyl group.

Claim 6

Disaccharides according to claim 3, wherein B represents an ―SO 3 M 2 group in which M 2 , identical or different from M 1 defined above, represents an alkali metal, in particular sodium.

Claim 7

Disaccharides according to claim 4 or 5, wherein R and R, are identical and represent an alkyl group, in particular methyl or indeed R and R 1 are different, R 1 representing an alkali metal; in particular sodium and R an alkyl radical in particular methyl.

Claim 8

Disaccharide characterised in that it corresponds to the formula IV: this disaccharide having an anti-Xa activity (Yin-Wessler) of 1,000 to 2,000 µ/g.

Claim 9

Disaccharide characterised in that it corresponds to the formula IV: this disaccharide having an anti-Xa activity (Yin-Wessler) of 1,000 to 2,000 µ/g.

Claim 10

Medicaments, characterised in that they comprise an effective amount of at least one disaccharide according to any one of claims 1 to 7.

Claim 11

Medicaments according to claim 8, characterised in that they are administered by oral or rectal route or under an injectable form.

Claim 12

Use of the disaccharides according to anyone of claims 1 to 7 as biological reagents.

Claim 13

Method of preparing disaccharides according to any one of claims 1 to 7, characterised by: - using two monosaccharides having respectively formulae V and VI: in which R 2 and R 3 represent two reactive groups permitting the establishment, selectively, of a 1,4 a bond, these groups being selected from among those compatible with the other groups of the monosaccharides; - Y 1 to Y s represent blocking groups enabling through their nature the introduction successively of the desired functional groups without the remaining blocking groups being affected, and - D represents a nitrogenous group precursor of a nitrogenous functional group -NHB as defined above, preferably an azide group; - R and R, have the above-indicated meanings, - performing a condensation reaction between said two monosaccharides to establish the desired 1,4 a bond, under conditions compatible with the various substituants of the monosaccharides, which results in a disaccharide of formula VII: - proceeding by successive steps with the introduction of the desired functional groups for a given disaccharide by bringing into play corresponding specific reactions, - liberating the hydroxyl groups at positions 2 and 3 of the uronic unit and positions 3 and 4 of the glucosamine unit and converting the -N 3 group into a -NH 2 group by subjecting the disaccharide to an hydrogenation step and, optionally ―subjecting the resulting disaccharide to the action of an acetylation or a sulfation agent to convert the -NH 2 group into -N-acetyl or -N-sulfate group, the latter being optionally obtained under the salt form and, if desired, - subjecting the resulting disaccharide to the action of a metallic hydroxide to form the corresponding carboxylate on the uronic unit.

Claim 14

Method according to claim 11, wherein Y 3 is constituted by a group enabling to further introduce at this position a sulfate group and more particularly represents an acetyl group.

Claim 15

Method according to any one of claims 11 or 12 wherein the blocking groups Y 1 , Y 2 , Y 4 and Y 5 which will be eliminated during the synthesis to liberate hydroxyl groups, are constituted by benzyl groups.

Claim 16

Method according to any one of claims 11 to 13 wherein R 2 represents a halide, preferably a bromide, or again a chloride, and R 3 an alcohol group.

Claim 17

Method according to any one of claims 11 to 14, wherein first the disaccharide VII is subjected to a hydrolysis reaction under the action of a strong base such as soda then to the action of an alkylating agent in order to maintain as substituent A, a ―COOR 1 group, optionally subjecting the disaccharide obtained, comprising a primary alcohol function―CH 2 OH at the 6 position of the D-glucosamine unit, to the action of a sulphating agent under conditions enabling the replacement of the -CH 2 0H group at the 6 position by a sulphate group without affecting the other blocking groups of the molecule as well as the azide group, a complex of trimethylamine and SO 3 being advantageously used to introduce a ―SO 3 Na group, then carrying out, as necessary, a hydrogenation reaction to liberate the -OH groups blocked by Y 1 , Y 2 , Y 4 and Y s and converting the N 3 group into a -NH 2 group and (if desired), to prepare a disaccharide comprising a D-glucosamine N-acetyl unit, treating the previously obtained disaccharide with an acetylating agent, in particular acetic anhydride, and to prepare a disaccharide comprising a D-glucosamine N-sulphate, the disaccharide obtained after the hydrogenation step is treated with a sulphating agent, these reactions being followed, is desired, by a treatment with a metal hydroxide in order to obtain a disaccharide comprising a carboxylate group at the 6 position of the glucuronic unit, advantageously with soda to form a -COONa group.

Claim 18

Intermediate compounds in the process according to claim 11 characterised in that they consist to the following disaccharides.