Heterobifunctional poly(ethylene glycol) and uses thereof

1. A compound of formula I′:

wherein:

n is 10-2500;

R 1 is —X(CH 2 CH 2 Y) m (CH 2 ) n′ R 3 , wherein:

X is —O—, —S—, —C≡C—, or —CH 2 —;

each Y is independently —O— or —S—;

m is 0-10;

n_′ is 0-10; and

R 3 is —N 3 , —CN, a mono-protected amine, a di-protected amine, a protected aldehyde, a protected hydroxyl, a protected carboxylic acid, a protected thiol, a 9-30 membered crown ether, or an optionally substituted group selected from aliphatic, a 5-8 membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, an 8-10 membered saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a detectable moiety;

R 2 is halogen, N 3 , CN, a mono-protected amine, a di-protected amine, a protected hydroxyl, a protected aldehyde, a protected thiol, —NHR 4 , —N(R 4 ) 2 , —SR 4 , —O(CH 2 CH 2 O) q (CH 2 ) r R 5 , —OC(O)R 4 , or —OS(O) 2 R 4 ;

q and r are each independently 0-4;

each R 4 is independently an optionally substituted group selected from aliphatic, a 5-8 membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, an 8-10-membered saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a detectable moiety, or:

two R 4 on the same nitrogen atom are taken together with said nitrogen atom to form an optionally substituted 4-7 membered saturated, partially unsaturated, or aryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur; and

R 5 is hydrogen, halogen, N 3 , CN, a mono-protected amine, a di-protected amine, a protected aldehyde, a protected hydroxyl, a protected carboxylic acid, a protected thiol, or an optionally substituted group selected from aliphatic, a 5-8 membered saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, an 8-10 membered saturated, partially unsaturated, or aryl bicyclic ring having 0-5 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a detectable moiety,

provided that:

(a) when either of R 1 or R 2 is (EtO) 2 CH—, then the other of R 1 or R 2 is not —S—S-pyridin-2-yl, —OBn, —OC(O)C(CH 3 )═CH 2 , or —OC(O)CH═CH—CH═CH-Ph;

(b) when either of R 1 or R 2 is —OBn, the other is not —OC(O)Cl;

(c) R 1 and R 2 are not simultaneously —OC(O)CH═CH 2 ;

(d) when either of R 1 or R 2 is —CN, then the other is not -phthalimido; and

(e) when either of R 1 or R 2 is acetyl, then the other is not —CN or -phthalimido.

2. The compound according to claim 1 , wherein the R 1 and R 2 groups of formula I′ are different from each other.

3. The compound according to claim 1 , wherein R 3 is an optionally substituted group selected from aliphatic or aryl.

4. The compound according to claim 3 , wherein R 3 is an aliphatic group substituted with one or more groups independently selected from CN, N 3 , trimethylsilyl, triisopropylsilyl, t-butyldimethylsilyl, N-methyl propiolamido, N-methyl-4-acetylenylanilino, N-methyl-4-acetylenylbenzoamido, bis-(4-ethynyl-benzyl)-amino, dipropargylamino, di-hex-5-ynyl-amino, di-pent-4-ynyl-amino, di-but-3-ynyl-amino, propargyloxy, hex-5-ynyloxy, pent-4-ynyloxy, di-but-3-ynyloxy, N-methyl-propargylamino, N-methyl-hex-5-ynyl-amino, N-methyl-pent-4-ynyl-amino, N-methyl-but-3-ynyl-amino, 2-hex-5-ynyldisulfanyl, 2-pent-4-ynyldisulfanyl, 2-but-3-ynyldisulfanyl, or 2-propargyldisulfanyl.

5. The compound according to claim 3 , wherein R 3 is an aryl group substituted with one or more groups independently selected from CN, N 3 , NO 2 , —CH 3 , —CH 2 N 3 , —CH═CH 2 , —C≡CH, Br, I, F, bis-(4-ethynyl-benzyl)-amino, dipropargylamino, di-hex-5-ynyl-amino, di-pent-4-ynyl-amino, di-but-3-ynyl-amino, propargyloxy, hex-5-ynyloxy, pent-4-ynyloxy, di-but-3-ynyloxy, 2-hex-5-ynyloxy-ethyldisulfanyl, 2-pent-4-ynyloxy-ethyldisulfanyl, 2-but-3-ynyloxy-ethyldisulfanyl, 2-propargyloxy-ethyldisulfanyl, bis-benzyloxy-methyl, [1,3]dioxolan-2-yl, or [1,3]dioxan-2-yl.

6. The compound according to claim 2 , wherein R 3 is a group suitable for Click chemistry.

7. The compound according to claim 6 , wherein R 3 is an azide-containing group or an alkyne-containing group.

8. The compound according to claim 1 , wherein said compound has a polydispersity index of about 1.0 to about 1.2.

9. The compound according to claim 1 , wherein n is about 200 to about 250.

10. The compound according to claim 1 , wherein n is about 100 to about 150.

11. The compound according to claim 1 , wherein n is about 400 to about 500.

12. The compound according to claim 1 , wherein said compound is selected from the group consisting of:

13. The compound according to claim 1 , wherein R 3 is a mono-protected or di-protected amino group.

14. The compound according to claim 13 , wherein R 3 is a mono-protected amino group.

15. The compound according to claim 14 , wherein R 3 is a mono-protected amino group selected from t-butyloxycarbonylamino, ethyloxycarbonylamino, methyloxycarbonylamino, trichloroethyloxy-carbonylamino, allyloxycarbonylamino, benzyloxocarbonylamino, allylamino, benzylamino, fluorenylmethylcarbonyl, formamido, acetamido, chloroacetamido, dichioroacetamido, trichloroacetamido, phenylacetamido, trifluoroacetamido, benzamido, and t-butyldiphenylsilylamino.

16. The compound according to claim 13 , wherein R 3 is a di-protected amino group.

17. The compound according to claim 16 , wherein R 3 is a di-protected amino group selected from di-benzylamine, di-allylamine, phthalimide, maleimide, succinimide, pyrrole, 2,2,5,5-tetramethyl-[1,2,5]azadisilolidine, and azide.

18. The compound according to any one of claims 13 - 17 , wherein R 2 is —OS(O) 2 R 4 , wherein R 4 is an optionally substituted aliphatic group, or an optionally substituted 5-8-membered aryl ring.

19. The compound according to claim 18 , wherein R 2 is p-toluenesulfonyloxy or methanesulfonyloxy.

20. The compound according to any one of claims 13 - 17 , wherein R 2 is a group suitable for Click chemistry.

21. The compound according to claim 20 , wherein R 2 is —N 3 .

22. The compound according to claim 1 , wherein R 2 is selected from the group consisting of:

23. The compound according to claim 1 , wherein R 1 is selected from the group consisting of:

R 1 Groups

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