IP Library Granted Patent US 8,299,173
Granted Patent B2
US 8,299,173 · App. 13/154,917 · Granted Oct 30, 2012

Method involving 1-benzotriazolyl carbonate esters of polymers

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Quick Facts
Patent No.
US 8,299,173
App. No.
13/154,917
Granted
Oct 30, 2012
Kind
B2
Abstract

The invention provides a method comprising the steps of (i) reacting a water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups with di(1-benzotriazolyl)carbonate to form a water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups; and (ii) reacting the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups with a water-soluble and non-peptidic polymer having three or more primary amino groups under conditions effective to form a cross-linked polymer composition.

Claims (9)

1. A method comprising reacting PEG-BTC esters with lysine.

2. The method of claim 1 , wherein the PEG-BTC esters have the following structure:

wherein R′ is a capping group.

3. The method of claim 2 , wherein the capping group is methoxy.

4. The method of claim 1 , wherein the PEG has an average molecular weight from about 200 Da to about 100,000 Da.

5. The method of claim 1 , resulting in the formation of a polymeric lysine derivative having the following structure:

wherein PEG is a poly(ethylene glycol) and Z is selected from the group consisting of H, N-succinimidyl, and 1-benzotriazolyl.

6. The method of claim 5 , wherein each PEG is capped with a capping group.

7. The method of claim 6 , wherein the capping group is methoxy.

Assignments (4)
RELEASE OF SECURITY INTEREST Recorded Apr 17, 2020
From: TC LENDING, LLC, AS COLLATERAL AGENT
To: NEKTAR THERAPEUTICS
Reel/Frame 053180/0009 →
RELEASE OF SECURITY INTEREST RECORDED AT REEL 28571, FRAME 0141 Recorded Oct 14, 2015
From: WELLS FARGO BANK, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
To: NEKTAR THERAPEUTICS
Reel/Frame 036866/0700 →
GRANT OF SECURITY INTEREST IN UNITED STATES PATENTS Recorded Oct 6, 2015
From: NEKTAR THERAPEUTICS
To: TC LENDING, LLC, AS COLLATERAL AGENT
Reel/Frame 036796/0562 →
GRANT OF SECURITY INTEREST Recorded Jul 17, 2012
From: NEKTAR THERAPEUTICS
To: WELLS FARGO BANK, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 028571/0141 →