METHOD INVOLVING 1-BENZOTRIAZOLYL CARBONATE ESTERS OF POLY(ETHYLENE GLYCOL)
The invention provides for preparing a polymer-active agent conjugate, the method comprising the steps of reacting an amino acid derivative with a biologically active agent under conditions to form a polymer-active agent conjugate.
1 . A method comprising:
(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.
2 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer within each of (a) the water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups, (b) the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups, and (c) the water-soluble and non-peptidic polymer having three or more primary amino groups is independently selected from the group consisting of poly(alkylene glycol), poly(oxyethylated polyol), poly(olefinic alcohol), poly(vinylpyrrolidone), poly(hydroxypropylmethacrylamide), poly(α-hydroxy acid), poly(vinyl alcohol), polyphosphazene, polyoxazoline, poly(N-acryloylmorpholine), and copolymers, terpolymers, and mixtures thereof.
3 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer within the water-soluble and non-peptidic polymer having three or more primary amino groups is selected from polyethylene glycol having a plurality of amino groups, proteins, aminocarbohydrates, and poly(vinylamine).
4 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer within each of (a) the water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups, and (b) the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups is a poly(ethylene glycol).
5 . The method of claim 4 , wherein the poly(ethylene glycol) has an average molecular weight from about 200 Da to about 100,000 Da.
6 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups has from 2 to 300 hydroxyl groups.
7 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups has the structure:
wherein POLY is a water-soluble and non-peptidic polymer backbone; and R′ is a 1-benzotriazolyl ester.
8 . The method of claim 7 , wherein POLY is poly(ethylene glycol).
9 . The method of claim 8 , wherein the poly(ethylene glycol) has an average molecular weight from about 200 Da to about 100.00 Da.
10 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups has the structure:
wherein:
POLY a and POLY b are each a water-soluble and non-peptidic polymer backbone that may be the same or different;
R is a central core molecule;
q is an integer from 2 to about 300; and
each X is independently either an inert capping group or a functional group, where at least one X is 1-benzotriazolyl ester.
11 . The method of claim 10 , wherein each of POLY a and POLY b is a poly(ethylene glycol).
12 . The method of claim 10 , wherein each of POLY a and POLY b has an average molecular weight from about 200 Da to about 100.00 Da.
13 . The method of claim 10 , wherein each X is independently selected from the group consisting of alkoxy, hydroxyl, protected hydroxyl, active ester, active carbonate, acetal, aldehyde, aldehyde hydrates, alkenyl, acrylate, methacrylate, acrylamide, active sulfone, protected amine, protected hydrazide, thiol, protected thiol, carboxylic acid, protected carboxylic acid, isocyanate, isothiocyanate, maleimide, vinylsulfone, dithiopyridine, vinylpyridine, iodoacetamide, epoxide, glyoxal, dione, mesylate, tosylate, and tresylate.
14 . The method of claim 1 , wherein step (i) is conducted in an organic solvent.
15 . The method of claim 14 , wherein the organic solvent is selected from the group consisting of methylene chloride, chloroform, acetonitrile, tetrahydrofuran, dimethylformamide, dimethylsulfoxide, and mixtures thereof.
16 . The method of claim 1 , wherein step (i) is conducted in the presence of base.
17 . The method of claim 16 , wherein the base is selected from the group consisting of pyridine, dimethylaminopyridine, quinoline, trialkylamines, and mixtures thereof.
18 . The method of claim 1 , wherein in step (i), the molar ratio of di(1-benzotriazolyl) carbonate to the number of hydroxyl groups associated with the water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups is about 30:1 or less.
19 . The method of claim 1 , wherein step (ii) is carried out in an aqueous medium.
20 . The method of claim 1 , wherein the water-soluble and non-peptidic polymer within each of (a) the water-soluble and non-peptidic polymer having two or more terminal hydroxyl groups, (b) the water-soluble and non-peptidic polymer having two or more 1-benzotriazolylcarbonate ester groups, and (c) the water-soluble and non-peptidic polymer having three or more primary amino groups comprises one or more degradable linkages.
21 . The method of claim 1 , said composition forming a hydrogel in aqueous media.
22 . The method of claim 1 , further comprising a biologically active agent.