Iduronic acid preparation

The amino sugar counterparts of D-glucuronic acid and nonsulfated L-iduronic acid in heparin are either N-acetylated, or nonsulfated at C-6, or both. 2-Acetamido-2-deoxy-D-glucosyl residues account for only a minor proportion of the total hexosamine in heparin, and are especially low in beef-lung preparations (see Table II).8,138,147 -149 In contrast, they... 

For the synthesis of D-glucuronic acid, methods of oxidation of suitable D-glucose derivatives have been devised during the past two decades these procedures have been comprehensively reviewed by Marsh,6 Mehltretter,7 and Heyns and Paulsen.8 For special purposes, for example, for the preparation of 6-I4C-labelled D-glucuronic acid, chain-extension reactions of 1,2-O-isopropylidene-a-D-xy/o-pen-todialdo-I,4-fiiranose by the cyanohydrin synthesis9 or by ethynyla-tion10 are used, but these frequently yield mixtures of D-glucuronic acid and L-iduronic acid. 

As a further illustration of the scope for use of 1,6-anhydro sugars in the preparation of uncommon sugars, the rare L-idose derivative 210 has been prepared recently and used in the preparation of oligosaccharides containing iduronic acid... 

A method based on the epimerization of 40 was used for the preparation of the L-iduronic acid derivative 60, a synthon for making glycosamino-glycan fragments.174... 

D. Horton and J.-H. Tsai, Preparation of derivatives of L-idose and L-iduronic acid from 1,2-O-isopropylidene-a-D-glucofuranose by way of acetylenic intermediates, Carbohydr. Res., 58 (1977) 89-108. 

Incidental to the studies on cellulose nitrate, specifically C-la-beled cotton celluloses were prepared biologically, and some insight into biosynthesis in the cotton boll was obtained. a-D-Glu-copyranosyl phosphate, the anomer of the Cori ester, was synthesized, and a synthetic route to L-iduronic acid was devised both of these products were subsequently found by others to occur naturally. 

Garg HG, Siebert JW, Garg A, Neame PJ. Inseparable iduronic acid-containing proteoglycan PG(IdoA) preparations of human skin and post-burn scar tissues evidence for elevated levels of PG(IdoA)-I in hypertrophic scar by N-terminal sequencing. Carbohydr Res 1996 284 223-228. 

L-Iduronic acid and D-glucuronic acid have been identified by g.l.c.-m.s. of the 0-TMS ethers of the corresponding hexuronolactones prepared from the glycuronan protuberic acid from Kobayasia nipponica ... 

The stability of ester sulphates in porcine intestinal heparin to solvolytic desulphation in dimethyl sulphoxide containing 2% pyridine has been compared to their stability when treatment is carried out in dilute acid. The modified preparations were deaminated and fractionated. The yields of disulphated disaccharide (64) and of monosulphated disaccharides (65) and (66) indicated that L-iduronic acid residues of heparin were more labile than the 6-O-sulphates in 2-acetamido-2-deoxy-D-glucosyl residues when treated with dilute acid, while the opposite was the case for the solvolysis. 

The L-iduronic acid-like 1-iV-imino sugars 39-41 have been prepared from a siastatin B derivative (See Vol. 27, p. 237, ref. 96) as metastasis inhibitors. The synthesis and glycosidase activity of other siastatin B analogues are mentioned in Chapter 19. 

A preparation of racemic 2,4-dldeoxyhexuronlc acid derivatives is outlined in Scheme 14. Reference is made to carbocycllc analogues of hexuronates in Chapter 18. A procedure for synthesizing L-iduronic acid derivatives by inversion at C-5 of D-glucuronic acid compounds is Indicated in Scheme 15, and the... 

In the field of 2-aniino-2-deoxY-D-glucose disaccharides the sugar in various derivatised forms has been linked to D-galactose (/9-1,3-link)(and /9-1,6-link),D-glucose (iS-l,3-link), 2-amino-2-deoxy-D-glucose (j8-l,4-link) D-galacturonic acid fi-1,2-link)and L-iduronic acid (a-l,4-link).The 2-amino-2,4-dideoxy-4-fluoro compound (55) has been prepared by the oxazoline method and 2-amino-2-deoxy- -D-mannopyranosyl disaccharides have been produced from oximo-products obtained by use of a 2-deoxy-2-oximo-D-arabino-hexosyl bromide. A 4-amino-4-deoxy-D-rhamnosyl disaccharide (a-l,2-linked) has been made by way of 4-azido-corapounds. 

In the field of aldobiouronic acid derivatives an ingenious method has been devised for the preparation of radioactive disaccharides for use as substrates for o-L-iduronidase, jS-D-glucuronidase, and 2-sulpho-L-iduronate 2-sulphatase. Heparin was cleaved by the deamination procedure and the products were reduced using sodium borotritide to afford access to a-L-idopyranosyluronic and j3-D-glucopyranosyluronic acid derivatives of 2,5-anhydro-D-[l- H]mannitol. Acidic treatment in methanol of the water-soluble polysaccharides of wobaku wood, followed by acetylation, have led to the isolation of the anhydride derivative (53) which was concluded to arise by way of the corresponding aldo-... 

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