Glycosaminoglycans chondroitin

Danaparoid (Orgaran mean MW, 6,000 Da) is a mixture of nonheparin glycosaminoglycans derived from pig gut (dermatan sulfate, heparan sulfate, chondroitin sulfate). Die anti-Xa/anti-IIa ratio (22 1) is even greater than seen with LMWH. Die anti-IIa effect may be mediated in part by dermatan sulfate, which catalyzes thrombin inhibition by heparin cofactor II. 

Fig. 34.—Circular Dichroism of Glycosaminoglycans (a) Hyaluronic Acid (b) Heparan Sulfate from Normal Mammalian Tissue (c) Chondroitin 4-Sulfate (d) Dermatan Sulfate ...

Fig. 19 Structures of glycosaminoglycans (A) chondroitin-4-sulfate (B) heparin sulfate (C) dermatin sulfate (D) hyaluronic acid (E) chondroitin-6-sulfate (F) keratin sulfate. 

Dermatan sulfate, also termed chondroitin sulfate B, a related glycosaminoglycan constituent of connective tissue, was known to be composed of galactosamine and a uronic acid, originally believed to be glucuronic acid but then claimed to be iduronic acid based largely on color reactions and paper chromatography. However, the d or L-enantiomer status of the latter monosaccharide was not clear. Jeanloz and Stoffyn unequivocally characterized the monosaccharide as L-iduronic acid by consecutive desulfation, reduction, and hydrolysis of the polysaccharide, followed by isolation of the crystalline 2,3,4-tri-0-acetyl-l,6-anhydro-/ -L-idopyranose, which was shown to be identical to an authentic specimen synthesized from 1,2-0-isopropylidene-/ -L-idofuranose.34... 

Another example in which the reaction of a glycosylthiol 52 displaces a triflate on a second sugar 53, generating a thiodisaccharide 54 is reported in Fig. 24 for the synthesis of a mimetic of glycosaminoglycan chondroitin (55).53... 

Through the combined approach of l.c. and the sequential applications of specific glycosaminoglycan-lyases, it is possible to determine the levels of several different glycosaminoglycans in the same tissue-sample. Thus, Gurr and coworkers demonstrated that hyaluronate, chondroitin sulfate... 

Fig. 2. Kinetics of cross-linking of chondroitin 6-sulfate, a glycosaminoglycan (GAG), to collagen following exposure to 105 °C under 6.7 Pa (50 mtorr). The mechanism of cross-linking is most probably interchain amide condensation involving e-amino groups of lysyl residues on collagen chains with carboxylic groups on glucuronic acid residues in neighboring GAG chains (From [30] with permission).

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