SK278960B6 - 0-2,3-dihydroxopropyl-£(4-0-methyl)-alpha-d-glucorono)-beta-d- -xylane|, its potassium and natrium salt - Google Patents

Abstract

(4-0-methyl-alpha-D-glucorono)-beta-D-xylane is activated in formic acid, trifluoroethane acid or water solution containing acid, hydrochloric acid as for instance, for 5 minutes up to two hours, at the temperature 10 up 30 Celsius degrees and it is modified subsequently with the use of 1-chloro-2,3-epoxypropane at the temperature 10 up to 30 Celsius degrees, for 15 minutes up to 4 hours, while the ratio of (4-0-methyl-alpha-D-glucorono)- -beta-D-xylane, solvent and 1-chloro-2,3-epoxypropane is 1 : 15 up to 25 : 5 up to 10, or it is alkalised with the use potassium or sodium hydroxide and the pH value is in the interval 11,5 up to 12,5 and the subsequent processing is provided, while well known procedures are applied and 0-2,3-dihydroxopropyl-[(4-0- -methyl)-alpha-D-glucorono)-beta-D-xylane].

Description

Technical field

The invention relates to O-2,3-dihydroxypropyl - [(4-O-methyl-α-D-glucurono) -β-D-xylan]. its potassium and sodium salts.

BACKGROUND OF THE INVENTION

Non-cellulosic polysaccharides find increasing use in practice (WO Pat. 88 00211; JP Pat. 63243400; WO Pat. 88 08257; JP Pat. 01 62303; EP Pat. 298171; EP Pat. 303040; EP Pat. 313463, JP Pat. 63,296,661). Their chemical modification produces products with biological activity, gel-forming, water-binding properties, which can find application in medicine, food, cosmetics and waste water treatment. It is realistic that in many of these applications these derivatives will replace analogous cellulose and starch derivatives that have priority in the paper and food industries. The prior art processes for the preparation of hydroxypropylcellulose use propylene oxide to modify which produces water-soluble monofunctional derivatives (JP Pat. 63205301). If it is desired to use epichlorohydrin for modification in order to prepare a monofunctional bound polysaccharide ether, the modification must be carried out in the presence of acids (JP pat. 01101301). A disadvantage of the hitherto known processes is the non-use of (4-O-methyl-α-D-glucorono) -β-D-xylan as a substrate for the preparation of similar derivatives. 0-2,3-Dihydroxypropyl - [(4-O-methyl-α-D-glucorono) -3-D-xylan], its potassium and sodium salts have not been prepared.

SUMMARY OF THE INVENTION

These drawbacks are overcome by the present invention. The present invention provides 0-2,3-dihydroxypropyl - [(4-O-methyl-α-D-glucuronium) -β-D-xylan] with a structural unit of formula (I)

R in which

R 1 represents hydroxy-, 2,3-dihydroxypropoxysubstituent and R ₂ represents hydroxy-, 2,3-dihydroxypropoxysubstituent and the structural unit of 4-O-methyl-α-D-glucoronic acid of formula (II)

in which

R 1 is as defined above, or is a structural unit of 4-O-methyl-α-D-glucuronate of formula (III)

in which

R 1 is as defined above and

R ₃ represents sodium or potassium, wherein the polymerization degree of (1-> 4) -PD-xylan is 80 to 100, the content of structural units of formula (II) and (III) is 10 to 20 wt. % and the total degree of substitution of 2,3-dihydroxypropyl substituent is 0.1 to 2.2, obtainable by (4-O-methyl-αD-glucurono) -βD-xylan being activated in formic acid, trifluoroethanoic acid, water or aqueous of an acid solution such as hydrochloric acid for 5 min. up to 2 hours at 10-30 ° C and subsequently modified with 1-chloro-2,3-epoxypropane at 10-30 ° C for 15 min. up to 4 hours, the ratio by weight of (4-O-methyl-.alpha.-D-glucuronium) -PD-xylan, solvent and 1-chloro-2,3-epoxypropane to each other is 1: 15 to 25: 5 to 10; The mixture was basified with aqueous potassium or sodium hydroxide solution to pH 11.5 to 12.5 and then worked up by known procedures.

The advantage of O-2,3-dihydroxypropyl - [(4-O-methyl-.alpha.-D-glucurono) -PD-xylan] with a degree of substitution of 0.1 to 2.2 of 2,3-dihydroxypropylsubstituent over the known hydroxypropyl cellulose or starch derivatives is that It does not contain primary hydroxyl groups.

DETAILED DESCRIPTION OF THE INVENTION

These examples illustrate but do not limit the scope of the invention.

Example 1

0.7 g of (4-O-methyl-α-D-glucurono) -β-D-xylan with an average polymerization degree of 80 is activated for 45 min. at 30 ° C in 20 ml of water with stirring. 9.3 g of 1-chloro-2,3-epoxypropane are added and stirred for 4 hours. at 30 ° C. Dialysis followed by lyophilization afforded 0.8 g of 0-2,3-dihydroxypropyl - [(4-O-methyl-α-D-glucurono) -β-D-xylan] with a degree of substitution of 0.1.

Example 2

The procedure is as in Example 1 except that (4-O-methyl-α-D-glucuronium) -β-D-xylan with a polymerization degree of 100 is activated with 1 mol / L hydrochloric acid at 10 ° C. 9.3 g of 1-chloro-2,3-epoxypropane are added with stirring and stirred for 4 hours. at 10 ° C. 0.9 g of O-2,3-dihydroxypropyl - [(4-O-methyl-α-D-glucurono) -β-D-xylan] with a degree of substitution of 0.3 is obtained.

Example 3

The procedure is as in Example 1 except that (4-O-methyl-.alpha.-D-glucurono) - .beta.-D-xylan is activated with 18.5 g of formic acid for 5 min. at 20 ° C with stirring. 9.3 g of 1-chloro-2,3-epoxypropane are added and stirred for 2 hours. at 20 ° C. The reaction mixture was diluted with water and adjusted to pH 11.5 with sodium hydroxide. After work-up in a manner known per se, 1.1 g of 0-2,3-dihydric sodium salt are obtained

Droxypropyl-O- (4-O-methyl-.alpha.-D-glucurono) -3-D-xylan with a degree of substitution of 2.0 and an ash content of 1.2 wt. %.

Example 4

The procedure is as in Example 3, except that (4-O-methyl-α-D-glucurono) -β-D-xylan is activated with stirring with 23.2 g of trifluoroethanoic acid and adjusted to pH 12.5 with potassium hydroxide. 1.0 g of potassium salt of 0-2,3-dihydroxypropyl - [(4-O-methyl-.alpha.-D-gliicuron) -. Beta.-D-xylan] with a degree of substitution of 2.2 and an ash content of 1 is obtained, 2 wt. %.

hydrochloric selines for 5 min. up to 2 hours at 10-30 ° C and subsequently modified with 1-chloro-2,3-epoxypropane at 10-30 ° C for 15 min. up to 4 hours, the ratio by weight of (4-O-methyl-α-D-glucurono) -4-D-xylan, solvent and 1-chloro-2,3-epoxypropane to 1: 15 to 25: 5 to 10, optionally it is then basified with an aqueous potassium or sodium hydroxide solution to a pH of 11.5 to 12.5 and subsequently worked up by known methods.

End of document

Industrial usability

0-2,3-Dihydroxypropyl - [(4-O-methyl-α-D-glucuronium) -β-D-xylan], its potassium and sodium salts can find widespread use in the healthcare, cosmetics, food and paper industries.

Claims (1)

0-2,3-Dihydroxypropyl - [(4-O-methyl-α-D-glucurono) -β-D-xylan], its potassium and sodium salts with the structural unit of formula (I), R of which R 1 is hydroxy-, 2,3-dihydroxypropoxysubstituent and R ₂ is hydroxy-, 2,3-dihydroxypropoxysubstituent or a structural unit of 4-O-methyl-α-D-glucuronic acid of formula (II) wherein: R 1 is as defined above, or is a structural unit of 4-O-methyl-α-D-glucuronate of formula (III), wherein: R 1 is as defined above and R ₃ represents sodium or potassium, wherein the polymerization degree of (1-> 4) ^ - D-xylan is 80 to 100, the content of structural units of formula (II) and (III) is 10 to 20 wt. % and the total degree of substitution by the 2,3-dihydroxypropyl substituent is 0.1 to 2.2, obtainable by (4-O-methyl-α-D-glucuronoyl-1-D-xylan) being activated in formic acid, trifluoroethanoic acid, water or an aqueous solution of acid-