Method of making releasable polymeric reagents
Inventors
Culbertson, Sean M. • McManus, Samuel P. • Kozlowski, Antoni • Somu, Venkata Ravidnranadh
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11932726-B2
Publication Date
2024-03-19
Expiration Date
Abstract
The instant disclosure provides (among other things) improved methods of preparing fluorenyl-based polymeric reagents, methods of recovering and purifying such polymeric reagents, methods of reducing unwanted impurities in a fluorenyl-based polymeric reagent, fluorenyl-based polymeric reagents prepared by the methods described herein, and conjugates prepared by reaction with fluorenyl-based polymeric reagents prepared by the methods described herein.
Core Innovation
The disclosure describes methods for preparing reactive polymeric reagents based on fluorene polymer architectures. A water-soluble 9-hydroxymethyl fluorene polymer is reacted to provide a water-soluble 9-methyl benzotriazolyl carbonate fluorene polymer and a water-soluble 9-methyl N-hydroxysuccinimidyl carbonate fluorene polymer. The method employs dibenzotriazolyl carbonate or disuccinimidyl carbonate in an aprotic organic solvent in the presence of a base under anhydrous conditions, followed by recovery of the product from the reaction mixture.
The document also describes reactive polymeric FMOC active carbonate routes that avoid phosgene or triphosgene and use diBTC as a reagent to form BTC carbonate intermediates convertible to NHS carbonate. It further states that removal of basic species and/or addition of acidic additives during isolation and/or post-reaction mitigates undesired polymeric fulvene formation.
Claims Coverage
The consolidated material includes two independent claims. They cover preparation of a water-soluble 9-methyl benzotriazolyl carbonate fluorene polymer and a water-soluble 9-methyl N-hydroxysuccinimidyl carbonate fluorene polymer from a water-soluble 9-hydroxymethyl fluorene polymer, each using an anhydrous aprotic base-mediated carbonate formation step followed by recovery from the reaction mixture.
Anhydrous aprotic conversion with dibenzotriazolyl carbonate
Reacting a water-soluble 9-hydroxymethyl fluorene polymer with dibenzotriazolyl carbonate in an aprotic organic solvent in the presence of a base under anhydrous conditions to provide a water-soluble 9-methyl benzotriazolyl carbonate fluorene polymer.
Precipitation recovery using an anhydrous precipitation solvent
Recovering the water-soluble 9-methyl benzotriazolyl carbonate fluorene polymer by precipitation with an anhydrous solvent effective to promote precipitation of the polymer.
Disuccinimidyl carbonate NHS-ester activation of a water-soluble 9-hydroxymethyl fluorene polymer
Reacting a water-soluble 9-hydroxymethyl fluorene polymer with disuccinimidyl carbonate in an anhydrous aprotic organic solvent in the presence of a base to provide a water-soluble 9-methyl N-hydroxysuccinimidyl carbonate fluorene polymer.
Recovery of the water-soluble 9-methyl N-hydroxysuccinimidyl carbonate fluorene polymer
Recovering the water-soluble 9-methyl N-hydroxysuccinimidyl carbonate fluorene polymer from the reaction mixture.
The inventive concept is centered on converting a water-soluble 9-hydroxymethyl fluorene polymer into reactive carbonate-activated fluorene polymers under anhydrous aprotic/base conditions, followed by recovery from the reaction mixture.
Stated Advantages
Improve yield.
Reduce formation of polymer-substituted fulvene during conjugate formation.
Reduces PEG2 fulvene impurities.
Improves conjugate quality.
Alters in vivo release by mitigating reactive fulvene impurities that would otherwise change release behavior.
Provides avoidance of phosgene and precursors in the activation strategy.
Improves stability and reduces fulvene/impurity formation during preparation and handling, including effects of acidic additives during precipitation and storage.
Improves storage stability, including retention of substitution percent during storage.
Documented Applications
Conjugate formation for thiol therapeutic agent/protein conjugation and release.
Conjugates with amine-containing biologically active agents formed using the prepared reactive fluorene polymer reagents.
Conversion of recovered BTC intermediates to NHS-active carbonate structures, including NHS active carbonate ester structures.
Direct activation and handling to form NHS carbonates and storage under dry inert conditions.
Purification and processing approaches for fulvene impurity and substitution retention, including thiol resin purification concepts.
Interested in licensing this patent?