- PROCESS FOR PREPARING HEPARINOIDS AND INTERMEDIATES USEFUL IN THE SYNTHESIS THEREOF
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Processes are disclosed for the synthesis of the Factor Xa anticoagulant fondaparinux and related compounds. Protected pentasaccharide intermediates and efficient and scalable processes for the industrial scale production of fondaparinux sodium by conversion of the protected pentasaccharide intermediates via a sequence of deprotection and sulfonation reactions are provided.
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Page/Page column 14
(2013/02/28)
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- Synthesis of heparin partial structures and their binding activities to platelets
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A synthetic pentasaccharide corresponding to the antithrombin III-binding region in heparin was also found to bind to human platelets. To identify the platelet-binding site in the pentasaccharide which is expected to be a novel sequence in heparin responsible for its platelet-binding, five partial structures of this particular pentasaccharide were synthesized. In a competitive assay using [3H]-heparin, a trisaccharide, O-(2-deoxy-2-sulfamido-3,6-di-O-sulfo-α-D-glucopyranosyl)- (1→4)-O-(2-O-sulfo-α-L-idopyranosyluronic acid)-(1→4)-2-deoxy-2-sulfamido-6-O-sulfo-α-D-glucopyranose, was concluded to be a high-affinity site for heparin's binding to platelets.
- Koshida, Shuhei,Suda, Yasuo,Sobel, Michael,Ormsby, Julie,Kusumoto, Shoichi
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p. 3127 - 3132
(2007/10/03)
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- SYNTHESIS OF AN ANTITHROMBIN BINDING HEPARIN-LIKE PENTASACCHARIDE LACKING 6-O SULPHATE AT ITS REDUCING END.
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The synthesis of a pentasaccharide of the structure of the antithrombin (AT-III) binding sequence, but lacking the 6-O sulphate group at the reducing end, is described and its α-Xa activity determined.
- Beetz, T.,Boeckel, C. A. A. van
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p. 5889 - 5892
(2007/10/02)
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- SYNTHESIS OF HEPARIN FRAGMENTS. A CHEMICAL SYNTHESIS OF THE TRISACCHARIDE O-(2-DEOXY-2-SULFAMIDO-3,6-DI-O-SULFO-α-D-GLUCOPYRANOSYL)-(1->4)-O-(2-O-SULFO-α-L-IDOPYRANOSYL-URONIC ACID)-(1->4)-2-DEOXY-2-SULFAMIDO-6-O-SULFO-D-GLUCOPYRANOSE HEPTASODIUM SALT
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Known 3-O-benzyl-1,2-O-isopropylidene-α-D-glucofuranose was first converted into methyl 3-O-benzyl-1,2-O-isopropylidene-β-L-idofuranuronate.Acid hydrolysis, followed by acetylation and treatment with titanium tetrabromide, gave methyl (2,4-di-O-acetyl-3-O-benzyl-α-L-idopyranosyl bromide)uronate, which was immediately transformed into methyl 4-O-acetyl-3-O-benzyl-β-L-idopyranuronate 1,2-(tert-butyl orthoacetate).A two-step replacement of the 4-O-acetyl by a 4-O-chloroacetyl group gave the key derivative, crystalline methyl 3-O-benzyl-4-O-chloroacetyl-β-L-idopyranuronate 1,2-(tert-butyl orthoacetate).Condensation of this orthoester with an excess of crystalline benzyl 6-O-acetyl-3-O-benzyl-2-(benzyloxycarbonyl)amino-2-deoxy-α-D-glucopyranoside in chlorobenzene in the presence of 2,6-dimethylpyridinium perchlorate gave crystalline benzyl 6-O-acetyl-3-O-benzyl-2-(benzyloxycarbonyl)amino-2-deoxy-4-O-(methyl 2-O-acetyl-3-O-benzyl-4-O-chloroacetyl-α-L-idopyranosyluronate)-α-D-glucopyranoside in 40 percent yield.O-Demonochloroacetylation, followed by condensation with known 3,6-di-O-acetyl-2-azido-4-O-benzyl-2-deoxy-α-D-glucopyranosyl bromide in dichloromethane in the presence of 2,4,6-trimethylpyridine, silver triflate, and molecular sieve provided benzyl O-(3,6-di-O-acetyl-2-azido-4-O-benzyl-2-deoxy-α-D-glucopyranosyl)-(1->4)-O-(methyl 2-O-acetyl-3-O-benzyl-α-L-idopyranosyluronate)-(1->4)-6-O-acetyl-3-O-benzyl-2-(benzyloxycarbonyl)amino-2-deoxy-α-D-glucopyranoside in 88 percent yield.O-Deacetylation with sodium hydroxide, followed successively by O-sulfation in N,N-dimethylformamide in the presence of sulfur trioxide-trimethylamine complex, catalytic hydrogenolysis, and N-sulfation in water with the same sulfating agent, gave the heptasodium salt of O-(2-deoxy-2-sulfamido-3,6-di-O-sulfo-α-D-glucopyranosyl)-(1->4)-O-(2-O-sulfo-α-L-idopyranosyluronic acid)-(1->4)-2-deoxy-2-sulfamido-6-O-sulfo-D-glucopyranose.This trisaccharide, which is a fragment of the minimal antithrombin III-binding region in heparin, neither binds to antithrombin III nor induces anti-Xa activity.
- Jacquinet, Jean-Claude,Petitou, Maurice,Duchaussoy, Philippe,Lederman, Isidore,Choay, Jean,et al.
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p. 221 - 242
(2007/10/02)
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