Nucleotides and nucleosides and methods for their use in DNA sequencing

1. A method of identifying a plurality of bases in a target nucleic acid, comprising the following steps:

(i) attaching the 5′-end of a primer to a solid surface;

(ii) hybridizing a target nucleic acid to the primer attached to the solid surface;

(iii) adding a compound of the formula:

wherein:

Z is —O—, —S—, —NH—, —OC(O)O—, —NHC(O)O—, —OC(O)NH— or —NHC(O)NH—;

R 1 is triphosphate or α-thiotriphosphate;

R 2 is hydrogen or hydroxy;

R 3 and R 4 are each independently:

hydrogen, hydroxy, halo or amino; or

alkyl (C≦12) , alkenyl (C≦12) , alkynyl (C≦12) , aryl (C≦12) , aralkyl (C≦12) , heteroaryl (C≦12) , heteroaralkyl (C≦12) , alkoxy (C≦12) , aryloxy (C≦12) , aralkoxy (C≦12) , hetero-aryloxy (C≦12) , heteroaralkoxy (C≦12) , alkylamino (C≦12) , dialkylamino (C≦12) , arylamino (C≦12) , aralkyl-amino (C≦12) , or a substituted version of any of these groups; or

R 5 , R 7 , and R 8 are each independently:

hydrogen, hydroxy, halo, amino, nitro, cyano or mercapto;

alkyl (C≦12) , alkenyl (C≦12) , alkynyl (C≦12) , aryl (C≦12) , aralkyl (C≦12) , heteroaryl (C≦12) , heteroaralkyl (C≦12) , acyl (C≦12) , alkoxy (C≦12) , alkenyloxy (C≦12) , alkynyl-oxy (C≦12) , aryloxy (C≦12) , aralkoxy (C≦12) , heteroaryl-oxy (C≦12) , heteroaralkoxy (C≦12) , acyloxy (C≦12) , alkylamino (C≦12) , dialkylamino (C≦12) , alkoxy-amino (C≦12) , alkenylamino (C≦12) , alkynylamino (C≦12) , arylamino (C≦12) , aralkylamino (C≦12) , heteroaryl-amino (C≦12) , heteroaralkylamino (C≦12) , alkyl-sulphonylamino (C≦12) , amido (C≦12) , alkylthio (C≦12) , alkenylthio (C≦12) , alkynylthio (C≦12) , arylthio (C≦12) , aralkylthio (C≦12) , heteroarylthio (C≦12) , heteroaralkyl-thio (C≦12) , acylthio (C≦12) , thioacyl (C≦12) , alkyl-sulfonyl (C≦12) , arylsulfonyl (C≦12) , alkyl-ammonium (C≦12) , alkylsulfonium (C≦12) , alkyl-silyl (C≦12) , or a substituted version of any of these groups;

R 6 is a -linker-reporter;

or a salt thereof;

(iv) adding a nucleic acid replicating enzyme to the hybridized primer/target nucleic acid complex to incorporate the compound of step (iii) into the growing primer strand, wherein the incorporated compound of step (iii) terminates the polymerase reaction at an efficiency of between about 70% to about 100%;

(v) washing the solid surface to remove unincorporated components;

(vi) detecting the reporter group of the incorporated compound of step (iii);

(vii) a photochemical cleavage step to remove the terminating moiety of the incorporated compound, wherein the terminating moiety has the formula:

(viii) washing the solid surface to remove the cleaved terminating moiety; and

(ix) repeating steps (iii) through (viii) one or more times to identify the plurality of bases in the target nucleic acid.

2. A method of identifying a plurality of bases in a target nucleic acid, comprising the following steps:

(i) attaching the 5′-end of a target nucleic acid to a solid surface;

(ii) hybridizing a primer to the target nucleic acid attached to the solid surface;

(iii) adding a compound of the formula:

wherein:

Z is —O—, —S—, —NH—, —OC(O)O—, —NHC(O)O—, —OC(O)NH— or —NHC(O)NH—;

R 1 is triphosphate or α-thiotriphosphate;

R 2 is hydrogen or hydroxy;

R 3 and R 4 are each independently:

hydrogen, hydroxy, halo or amino; or

alkyl (C≦12) , alkenyl (C≦12) , alkynyl (C≦12) , aryl (C≦12) , aralkyl (C≦12) , heteroaryl (C≦12) , heteroaralkyl (C≦12) , alkoxy (C≦12) , aryloxy (C≦12) , aralkoxy (C≦12) , hetero-aryloxy (C≦12) , heteroaralkoxy (C≦12) , alkylamino (C≦12) , dialkylamino (C≦12) , arylamino (C≦12) , aralkyl-amino (C≦12) , or a substituted version of any of these groups; or

R 5 , R 7 , and R 8 are each independently:

hydrogen, hydroxy, halo, amino, nitro, cyano or mercapto;

alkyl (C≦12) , alkenyl (C≦12) , alkynyl (C≦12) , aryl (C≦12) , aralkyl (C≦12) , heteroaryl (C≦12) , heteroaralkyl (C≦12) , acyl (C≦12) , alkoxy (C≦12) , alkenyloxy (C≦12) , alkynyl-oxy (C≦12) , aryloxy (C≦12) , aralkoxy (C≦12) , heteroaryl-oxy (C≦12) , heteroaralkoxy (C≦12) , acyloxy (C≦12) , alkylamino (C≦12) , dialkylamino (C≦12) , alkoxy-amino (C≦12) , alkenylamino (C≦12) , alkynylamino (C≦12) , arylamino (C≦12) , aralkylamino (C≦12) , heteroaryl-amino (C≦12) , heteroaralkylamino (C≦12) , alkyl-sulphonylamino (C≦12) , amido (C≦12) , alkylthio (C≦12) , alkenylthio (C≦12) , alkynylthio (C≦12) , arylthio (C≦12) , aralkylthio (C≦12) , heteroarylthio (C≦12) , heteroaralkyl-thio (C≦12) , acylthio (C≦12) , thioacyl (C≦12) , alkyl-sulfonyl (C≦12) , arylsulfonyl (C≦12) , alkyl-ammonium (C≦12) , alkylsulfonium (C≦12) , alkyl-silyl (C≦12) , or a substituted version of any of these groups;

R 6 is a -linker-reporter;

or a salt thereof;

(iv) adding a nucleic acid replicating enzyme to the hybridized primer/target nucleic acid complex to incorporate the compound of step (iii) into the growing primer strand, wherein the incorporated compound of step (iii) terminates the polymerase reaction at an efficiency of between about 70% to about 100%;

(v) washing the solid surface to remove unincorporated components;

(vi) detecting the reporter group of the incorporated compound of step (iii);

(vii) optionally adding one or more chemical compounds to permanently cap unextended primers;

(viii) a photochemical cleavage step to remove the terminating moiety of the incorporated compound, wherein the terminating moiety has the formula:

(ix) washing the solid surface to remove the cleaved terminating moiety; and

(x) repeating steps (iii) through (ix) one or more times to identify the plurality of bases in the target nucleic acid.

3. The method of claim 1 , wherein the compound is incorporated by a nucleic acid replicating enzyme that is a DNA polymerase.

4. The method of claim 1 , wherein the photo-cleavage is performed using a wavelength of light ranging between 300 nm to 400 nm.

5. The method of claim 1 , wherein Z is —O—.

6. The method of claim 1 , wherein R 1 is a triphosphate.

7. The method of claim 1 , wherein R 1 is α-thiotriphosphate.

8. The method of claim 1 , wherein R 2 is hydrogen.

9. The method of claim 1 , wherein R 3 is alkyl (C≦12) or a substituted version thereof.

10. The method of claim 1 , wherein R 3 is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl and tert-butyl.

11. The method of claim 1 , wherein R 3 is tert-butyl.

12. The method of claim 1 , wherein R 4 is hydrogen.

13. The method of claim 1 , wherein R 5 is hydrogen.

14. The method of claim 1 , wherein the linker of the -linker-reporter is:

wherein

X is

—O—, —S—, or —NH—; or

alkanediyl (C≦12) , alkenediyl (C≦12) , alkynediyl (C≦12) , arenediyl (C≦12) , heteroarenediyl (C≦12) , or a substituted version of any of these groups; and

n is an integer from 0-12.

15. The method of claim 14 , wherein X is —C≡C—.

16. The method of claim 14 , wherein n is zero.

17. The method of claim 14 , wherein the reporter is:

18. The method of claim 1 , wherein R 7 is hydrogen.

19. The method of claim 1 , wherein R 8 is hydrogen.