Supports for oligomer synthesis

1. A compound of the formula I:

wherein:

R w and R x are each, independently, H, alkyl or substituted alkyl;

R a and R b are each, independently, H, a protecting group, a protected or unprotected nucleosidyl moiety, a protected or unprotected nucleosidyl moiety attached through a phospholinker, or a protected or unprotected oligonucleotidyl moiety;

Y is alkylene, cycloalkylene, arylene, heteroarylene, arylalkylene, alkarylene, or alkylenearylalkylene;

E is a bond, (CH 2 ) i C(═O) or C(═O)(CH 2 ) j C(═O) wherein i is from 0 to 20 and j is from 1 to 20; and

SM is a support medium.

2. The compound of claim 1 wherein Y is arylene, heteroarylene or arylalkylene.

3. The compound of claim 2 wherein Y is arylene or heteroarylene.

4. The compound of claim 3 wherein Y is arylene.

5. The compound of claim 4 wherein Y is phenylene.

6. The compound of claim 5 wherein Y is 1,4-phenylene.

7. The compound of claim 2 wherein Y is arylalkylene.

8. The compound of claim 7 wherein Y is benzylene.

9. The compound of claim 8 wherein Y is 1,4-benzylene.

10. The compound of claim 4 wherein E is (CH 2 ) i C(═O).

11. The compound of claim 10 wherein i is 0.

12. The compound of claim 11 wherein Y is 1,4-phenylene.

13. The compound of claim 4 wherein E is C(═O)(CH 2 ) j C(═O).

14. The compound of claim 13 wherein j is 2.

15. The compound of claim 1 wherein one of R a and R b is a base labile hydroxyl protecting group.

16. The compound of claim 15 wherein the other of R a and R b is an acid labile hydroxyl protecting group.

17. The compound of claim 16 wherein R a is an acid labile hydroxyl protecting group and R b is a base labile hydroxyl protecting group.

18. The compound of claim 17 wherein the acid labile hydroxyl protecting group is 4-methoxytriphenylmethyl, 4,4′-dimethoxytriphenylmethyl, 9-phenylxanthenyl or substituted 9-phenylxanthenyl.

19. The compound of claim 18 wherein the acid labile hydroxyl protecting group is 4,4′-dimethoxytriphenylmethyl.

20. The compound of claim 19 wherein the base labile hydroxyl protecting group is an acyl group.

21. The compound of claim 20 wherein the base labile hydroxyl protecting group is benzyloxycarbonyl, 4-nitrobenzyloxycarbonyl, 4-bromobenzyloxycarbonyl, 4-methoxybenzyloxycarbonyl, methoxycarbonyl, tert-butoxycarbonyl, isopropoxycarbonyl, diphenylmethoxycarbonyl, 2,2,2-trichloroethoxycarbonyl, 2-(trimethylsilyl)ethoxycarbonyl, 2-furfuryloxycarbonyl, allyloxycarbonyl, acetyl, formyl, chloroacetyl, trifluoroacetyl, methoxyacetyl, phenoxyacetyl or benzoyl.

22. The compound of claim 21 wherein the base labile hydroxyl protecting group is acetyl.

23. The compound of claim 1 wherein the support material is controlled pore glass, oxalyl-controlled pore glass, silica-containing particles, polystyrene, copolymers of polystyrene, and divinylbenzene, copolymers of dimethylacrylamide and N,N-bisacryloylethylenediamine, a soluble support medium or PEPS.

24. The compound of claim 23 wherein the support material is controlled pore glass, polystyrene or copolymers of polystyrene.

25. The compound of claim 1 wherein one of R w , and R x is alkyl or substituted alkyl.

26. The compound of claim 1 wherein R w and R x are each H.

27. The compound of claim 26 wherein Y is 1,4-phenylene, E is C(═O), one of R a and R b is an acid labile hydroxyl protecting group and the other of R a and R b is a base labile protecting group.

28. The compound of claim 27 wherein R a is an acid labile hydroxyl protecting group and R b is a base labile hydroxyl protecting group.

29. The compound of claim 28 wherein the acid labile hydroxyl protecting group is 4,4′-dimethoxytriphenylmethyl and the base labile hydroxyl protecting group is an acyl group.

30. The compound of claim 29 wherein the acyl group is C(═O)CH 3 .

31. The compound of claim 30 wherein the support material is controlled pore glass, polystyrene or copolymers of polystyrene.