Chitin sulfation

SCM-Chitin (sulfated and carboxymethylated chitin) (Mw = 10000 to 60000) Inhibits cell attachment and migration of BI6-BL6 melanoma cells through extracellular matrix 64... 

Sulfates o II H-O-S-O-R II o Chitin sulfate, arylsulfate esters, aromatic sulfate esters ls-Jt 2481.5-2482... 

Moskowitz, R. W., Schwartz, H. J., Michel, B., Ratnoff, O. D. and Astrup, T., Generation of kinin-like agents by chondroitin sulfate, heparin, chitin sulfate, and human articular cartilage possible patho-physiologic implications, /. Lab. Clin. Med., 76, 790, 1970. 

Nishimura, S.-I., Kai, H., Shinada, K., Yoshida, T., Tokura, S., Kurita, K., Nakashima, H., Yamamoto, N., and Uryu, T. (1998) Regioselective syntheses of sulfated polysaccharides specific anti HIV-1 activity of novel chitin sulfates. Carbohydr. Res., 306, 427—433. 

Chitin and chitosan derivatives have also been studied as blood compatible materials both in vivo and in vitro [520], Anticoagulant activity was greatest with O sulfated N acetyl chitosan, followed by N,0 sulfated chitosan, heparin, and finally sulfated N acetyl chitosan. The lipolytic activity was greatest for N,0 sulfated chitosan followed by heparin. The generally poor performance of chitosan was attributed to polyelectrolyte complexes with free amino groups present on the membrane surface. The O sulfate or acidic group at the 6 position in the hexosamine moiety was identified as the main active site for anticoagulant activity. 

Monosaccharides may possess functionalities other than hydroxyls. Amino sugars are aldoses or ketoses which have a hydroxyl group replaced by an amino functionality. 2-Amino-2-deoxy-glucose is one of the most abundant amino sugars it is a constituent of the polysaccharide chitin. It also appears in mammalian glycoproteins, linking the sugar chain to the protein. Monosaccharides may also be substituted with sulfates and phosphates. Furthermore, deoxy functions can often be present, and important examples of this class of monosaccharides are L-fucose and L-rhamnose. 

Sulfate diesters of chitin have been widely prepared because of their possible use as synthetic, blood anticoagulants. The sulfating reagent commonly used is chlorosulfonic acid in pyridine, but, more recently, chloro-sulfonic acid in 1,2-dichloroethane has been employed. Chitin disulfates can show up to 20 % of the anticoagulant potency of heparin, accompanied, in general, by only slight toxicity. ... 

Using sulfur trioxide complexes with pyridine, dioxane, iV,iV-dimethyl-aniline, or bis(2-chloroethyl) ether, sulfated chitins have also been prepared for use as thickeners in pastes, adhesives, and drilling muds. ... 

Chitosan is insoluble in water, concentrated acids, alkalis, alcohol, and acetone, but dissolves readily in dilute acids. Water-soluble salts of chitosan include the nitrate and the perchlorate. As described on p. 377, formation of chitosan sulfate and the color reaction of chitosan with iodine have been widely used as qualitative tests for the detection of chitin. Nitration of chitosan with a mixture of acetic and nitric acids or with absolute nitric acid enabled both the free ester and its nitrate salt to be isolated. The perchlorate salt of this ester was also prepared, but it was unstable. Chitosan can be W-acetylated to give products similar to chitin except for their greatly reduced chain-length W-formyl-, iV-propionyl-, JV-butyryl-, and iV-benzoyl-chitosan were also prepared. ... 

Figure 5.5.1. A scatter plot of the intensity of ion with m/z =125 as a function of ion with m/z = 43 for (a) chitin, (b) chondroitin sulfate, (c) chitosan, (d) capsular polysaccharide from Neiseria meningitidis [47], (e) teichuronic acid from Bacillus subtilis [47], (f) carrageenan, (g) alginic acid, (h) amylose, (i) agarose.

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