The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 29, 2011
Filed:
Feb. 09, 2011
J. Milton Harris, Huntsville, AL (US);
Antoni Kozlowski, Huntsville, AL (US);
Lihong Guo, Beijing, CN;
J. Milton Harris, Huntsville, AL (US);
Antoni Kozlowski, Huntsville, AL (US);
Lihong Guo, Beijing, CN;
Nektar Therapeutics, San Francisco, CA (US);
Abstract
Methods for preparing water soluble, non-peptidic polymers carrying carboxyl functional groups, particularly carboxylic acid functionalized poly(ethylene glycol) (PEG) polymers are disclosed, as are the products of these methods. In general, an ester reagent R(C═0)OR', wherein R′ is a tertiary group and R comprises a functional group X, is reacted with a water soluble, non-peptidic polymer POLY-Y, where Y is a functional group which reacts with X to form a covalent bond, to form a tertiary ester of the polymer, which is then treated with a strong base in aqueous solution, to form a carboxylate salt of the polymer. Typically, this carboxylate salt is then treated with an inorganic acid in aqueous solution, to convert the carboxylate salt to a carboxylic acid, thereby forming a carboxylic acid functionalized polymer.