Polymeric alpha-hydroxy aldehyde and ketone reagents and conjugation method

Patent metadata

Field	Value
Publication number	US-9579392-B2
Application number	US-201514951035-A
Country	US
Kind code	B2
Filing date	Nov 24, 2015
Priority date	Sep 11, 2008
Publication date	Feb 28, 2017
Grant date	Feb 28, 2017

Abstract

Provided herein are polymeric α-hydroxy aldehyde or α-hydroxy ketone reagents which can be conjugated to amine-containing compounds to form stable conjugates in a single-step reaction. In selected embodiments, the polymeric reagent itself incorporates an internal proton-abstracting (basic) functional group, to promote more efficient reaction. The substituent is appropriately situated, via a linker if necessary, to position the group for proton abstraction, preferably providing a 4- or 5-bond spacing between the abstracting atom and the hydrogen atom on the α-carbon. Also provided are methods of using the reagents and stable, solubilized conjugates of the reagents with biologically active compounds. In preferred embodiments, the polymeric component of the reagent or conjugate is a polyethylene glycol.

First claim

The invention claimed is:

1. A method of conjugating a water soluble polymer with a compound B—NH 2 having a reactive amine group, the method comprising
contacting the compound B—NH 2 with a water soluble polymeric reagent comprising a water soluble polymer and an α-hydroxy aldehyde or α-hydroxy ketone end group, respectively,
thereby forming a conjugate in which said water soluble polymer is linked to a moiety having the structure —C(═O)—CHR 1 —NH—B, where R 1 is hydrogen or methyl, respectively, and NH—B represents the residue of the amine-containing compound.

2. The method of claim 1 , wherein said polymeric reagent further comprises a proton-abstracting functional group containing a proton-abstracting atom selected from oxygen and nitrogen, situated such there is a 3- or 4-bond spacing between the proton-abstracting atom and the α-carbon of said α-hydroxy aldehyde or α-hydroxy ketone.

3. The method of claim 2 , wherein said spacing in said reagent is a 4-bond spacing.

4. The method of claim 1 , wherein said polymeric reagent has the structure I:

where
R 1 is selected from H, lower alkyl, and alkoxyalkyl;
R 4 is a two- or three-carbon chain which may be substituted with one or more groups selected from alkyl, alkenyl, aryl, alkoxy, halo, cyano, and a water soluble polymer; wherein the carbon adjacent to Cα is not substituted with hydroxy, and wherein two substituents on R 4 may together form an aliphatic or aromatic ring, and
NR 5 is a secondary or tertiary amino group which is linked to a water soluble polymer POLY via an optional spacer group Z, where R 5 is hydrogen or an alkyl group, which may form a ring with spacer group Z.

5. The method of claim 4 , wherein POLY is a polyethylene glycol (PEG).

6. The method of claim 5 , wherein R 4 is a three-carbon chain.

7. The method of claim 1 , wherein said polymeric reagent has the structure II:

where
POLY is a water soluble polymer;
R 1 is selected from H, alkyl, hydroxyalkyl, and alkoxyalkyl;
m is 0-12; and
each R 2 and R 3 is independently selected from H, alkyl, alkylene, hydroxy, amino, alkoxy, hydroxyalkyl, alkoxyalkyl, alkoxyalkylene, aminoalkyl, iminoalkyl, carboxylic acid, alkylcarboxylic acid, phosphate, alkylphosphate, and a further water soluble polymer,
wherein at most one R 2 or R 3 group is a water soluble polymer, and wherein two substituents R 2 and R 3 in —(CR 2 R 3 ) m — can together form a ring.

8. The method of claim 7 , wherein said group R 2 or R 3 and the value of m are selected such that an oxygen or nitrogen atom on R 2 or R 3 is separated from Cα by a four-bond path.

9. The method of claim 7 , wherein at most one group R 2 or R 3 is selected from aminoalkyl, iminoalkyl, carboxylic acid, alkylcarboxylic acid, phosphate, and alkylphosphate.

10. The method of claim 7 , wherein POLY is a polyethylene glycol.

11. The method of claim 7 , wherein one group R 2 or R 3 is selected from hydroxy, amino, alkoxy, hydroxyalkyl, alkoxyalkyl, alkoxyalkylene, aminoalkyl, iminoalkyl, carboxylic acid, alkylcarboxylic acid, phosphate, and alkylphosphate.

12. The method of claim 1 , wherein said polymeric reagent has the structure III:

where
(i) R 7 is CH(OH)—C(═O)—R 1 , and R 8 is selected from —C(═O)OH, —CH 2 OH, —C(═O)N(R 1 ) 2 , —CH 2 N(R 1 ) 2 , —OH, and —N(R 1 ) 2 ; or
(ii) R 7 is —CHR 1 CH(OH)—C(═O)—R 1 , and R 8 is —OH or —N(R 1 ) 2 ;
where each R 1 is independently selected from H, lower alkyl, and alkoxyalkyl; and
POLY is a water soluble polymer.

13. The method of claim 12 , wherein R 7 is —CH(OH)—C(═O)—R 1 , where R 1 is H or methyl, and R 8 is —C(═O)OH or —CH 2 NH 2 .

14. The method of claim 12 , wherein R 7 is —CHR 1 CH(OH)—C(═O)—R 1 , where each R 1 is independently H or methyl, and R 8 is —OH or —NH 2 .

15. The method of claim 1 , wherein the water soluble polymeric reagent has the following structure:

wherein m-PEG is CH 3 O—CH 2 CH 2 O—(CH 2 CH 2 O) m′ —CH 2 CH 2 ˜ and m′ is 2 to 4000.

16. The method of claim 15 , wherein m′ is 20 to 1000.

Assignees

• Nektar Therapeutics

Inventors

• Culbertson Sean M
• Shen Xiaoming
• Kozlowski Antoni
• Mcmanus Samuel P

Classifications

• C08G65/26

  from cyclic ethers and other compounds · CPC title

• C07K1/003 Primary

  by transforming the C-terminal amino acid to amides · CPC title

• A61P43/00

  Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00 · CPC title

• A61K38/00

  Medicinal preparations containing peptides (peptides containing beta-lactam rings A61K31/00; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, A61K31/00; ergot alkaloids of the cyclic peptide type A61K31/48; containing macromolecular compounds having statistically distributed amino acid units A61K31/74; medicinal preparations containing antigens or antibodies A61K39/00; medicinal preparations characterised by the non-active ingredients, e.g. peptides as drug carriers, A61K47/00) · CPC title

• C08G65/33313

  aromatic · CPC title