# US 2017/0283552 A1 · Methods for preparing polymeric reagents and compositions of polymeric reagents

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- Number: US 2017/0283552 A1
- Document ID: US20170283552A1
- Status: Published application
- Kind: A1
- Application number: 15/631,845
- Filed: 2017-06-23
- Published: 2017-10-05
- Earliest claimed: 2005-07-29
- Assignees: Nektar Therapeutics
- Applicants: Nektar Therapeutics
- Inventors: Antoni Kozlowski; Jon McKannan; Samuel P. McManus
- Web page: https://patentgrep.com/patent/US20170283552A1

## CPC

- C08G 65/33396: {having oxygen in addition to nitrogen}
- A61K 47/60: the organic macromolecular compound being a polyoxyalkylene oligomer, polymer or dendrimer, e.g. PEG, PPG, PEO or polyglycerol
- C07B 47/00: Formation or introduction of functional groups not provided for in groups C07B39/00 - C07B45/00
- C08G 65/329: with organic compounds
- C08G 65/332: containing carboxyl groups, or halides, or esters thereof
- C08G 65/48: Polymers modified by chemical after-treatment
- C08L 71/02: Polyalkylene oxides
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D)
- C07B: GENERAL METHODS OF ORGANIC CHEMISTRY; APPARATUS THEREFOR (preparation of carboxylic acid esters by telomerisation C07C67/47; telomerisation C08F)
- C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06)

## Abstract

Methods for preparing active carbonate esters of water-soluble polymers are provided. Also provided are other methods related to the active carbonate esters of water-soluble polymers, as well as corresponding compositions.

## Claims

### Claim 1

A synthetic method comprising:
(a) combining a composition comprising an aprotic solvent and a hydroxy-terminated, water-soluble polymer having the following structure:
CH3O—(CH2CH2O)n—CH2CH2—OH
wherein (n) is an integer from 2 to about 4000, with a composition comprising disuccinimidyl carbonate, wherein the composition comprising the disuccinimidyl carbonate is added such that there is an excess of the disuccinimidyl carbonate relative to the hydroxy-terminated, water-soluble polymer, to thereby result in a composition comprising an active carbonate ester of the water-soluble polymer having the following structure:
wherein (n) is an integer from 2 to about 4000, and unreacted disuccinimidyl carbonate;
(b) adding a composition comprising a reactive molecule selected from the group consisting of water, hydrogen sulfide, and a lower alkyl monobasic amine to the composition comprising the active carbonate ester of a water-soluble polymer and unreacted disuccinimidyl carbonate, wherein the composition comprising the reactive compound is added such that substantially all of the unreacted disuccinimidyl carbonate is substantially consumed wherein compositions resulting from step (a) are not isolated prior to conducting step (b).