Method of synthesising 6-deoxy-6-amino-β-D-glucopyranoside-containing polymers and their precursors

Patent metadata

Field	Value
Publication number	US-11021547-B2
Application number	US-201816765427-A
Country	US
Kind code	B2
Filing date	Nov 21, 2018
Priority date	Nov 21, 2017
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

The invention provides an improved method of synthesising derivatives of β-D-glucopyranoside-containing polymers, such as chitin, chitosan, cellulose, amylose, pullulan, curdlan, inulin, guar gum or cyclodextrin. The method includes reacting a polymer of formula (III) with a cyclic imide to form a polymer of formula (I) thereby introducing a nitrogen functionality at the 6-position and providing access to 6-deoxy-6-amino-β-D-glucopyranoside-containing polymers.

First claim

The invention claimed is:

1. A method for preparing a polymer of formula I

wherein:
X is —OH or —NR 1 R 2 ;
R 1 =R 2 =H; or R 1 =H and R 2 =acyl; or N, R 1 and R 2 together form an optionally substituted cyclic imide;
R 3 and R 4 are each independently H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted haloalkyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted acyl, optionally substituted aryl, or optionally substituted heteroaryl; or R 3 and R 4 together with the atoms to which they are attached form an optionally substituted cycloalkyl, an optionally substituted aryl or an optionally substituted heteroaryl; and
n is an integer from 10 to 3000;
the method comprising: reacting a polymer of formula III,

wherein R 5 is optionally substituted alkyl or optionally substituted aryl, with an optionally substituted cyclic imide anion to form the polymer of formula I:

2. The method of claim 1 , including reacting a polymer of formula II:

with a sulfonyl halide to form the polymer of formula III

wherein R 5 is optionally substituted alkyl or optionally substituted aryl.

3. The method of claim 2 , wherein the reaction with the sulfonyl halide is performed in DMAc.

4. The method of claim 2 , wherein the sulfonyl halide is a methane sulfonyl halide, a p-cymene sulfonyl halide or a toluene sulfonyl halide.

5. The method of claim 2 , wherein the polymer of formula II is reacted with from 3 to 10 molar equivalents of the sulfonyl halide based on the moles of monomer to form the polymer of formula III.

6. The method of claim 1 , wherein the cyclic imide anion is a succinimide anion or a phthalimide anion.

7. The method of claim 1 , wherein the polymer of formula I is further reacted with hydrazine to form a polymer of formula IV:

8. The method of claim 7 , wherein X in formula I is optionally substituted cyclic imide and X in formula IV is —NH 2 .

9. The method of claim 7 , wherein the reaction with hydrazine is performed in ethanol, N-methyl-2-pyrrolidone or water.

10. The method of claim 7 , wherein X is optionally substituted cyclic imide in both formula I and formula IV.

11. The method of claim 10 , wherein the reaction with hydrazine is performed in ethanol.

12. The method of claim 7 , further comprising reacting the polymer of formula IV in which X is —NHAcyl with a saponifying agent to form a polymer of formula V:

13. The method of claim 1 , wherein X is OH.

14. The method of claim 1 , comprising reacting cellulose, amylose, pullulan, guar gum or cyclodextrin having the formula:

with a sulfonyl halide to form the polymer of formula III where X is —OH.

Assignees

• Univ Cape Town

Inventors

• Jardine Moegamat Anwar
• Sayed Shakeela

Classifications

• C08B37/003

  Chitin, i.e. 2-acetamido-2-deoxy-(beta-1,4)-D-glucan or N-acetyl-beta-1,4-D-glucosamine; Chitosan, i.e. deacetylated product of chitin or (beta-1,4)-D-glucosamine; Derivatives thereof · CPC title

• C08B15/06 Primary

  containing nitrogen {, e.g. carbamates} · CPC title

• C07H7/06

  Heterocyclic radicals · CPC title

• C08B37/0012

  Cyclodextrin [CD], e.g. cycle with 6 units (alpha), with 7 units (beta) and with 8 units (gamma), large-ring cyclodextrin or cycloamylose with 9 units or more; Derivatives thereof · CPC title

• C08B33/00

  Preparation of derivatives of amylose · CPC title