IP Library Granted Patent US 12,398,162
Granted Patent B2
US 12,398,162 · App. 17/686,726 · Granted Aug 26, 2025

Guanine analogs as telomerase substrates and telomere length affectors

Inventors: Sergei M. Gryaznov (San Mateo, CA); Ronald A. Pruzan (Palo Alto, CA); Krisztina Pongracz (Oakland, CA)
Assignee: Geron Corporation
C07F9/65616C07D473/18
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Quick Facts
Patent No.
US 12,398,162
App. No.
17/686,726
Granted
Aug 26, 2025
Kind
B2
Abstract

This invention relates to compounds useful for inhibiting telomere elongation. More specifically, the invention provides nucleotide analogs that are incorporated into telomeres by telomerase thereby inhibiting elongation of telomeres. The compounds are use in treating cancer and other cell proliferative diseases.

Claims (112)

1. A method for inhibiting telomere elongation or shortening telomere length, the method comprising:

contacting a cell or a tissue with a compound of formula (III):

wherein

R 1 and R 2 are independently selected from —NR 1a R 1b and OR 1c ; wherein

R 1a and R 1b are independently selected from hydrogen, optionally substituted C 1-20 alkyl, optionally substituted polyamine, and —CH(R 1d )—C(O) OR 1e , wherein

R 1d is selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl, and substituted heteroarylalkyl; and

R 1e is hydrogen or C 1-6 alkyl;

R 1c is selected from hydrogen, alkyl, and aryl;

wherein at least one of R 1 and R 2 is —NR 1a R 1b ;

R 3a and R 3b are independently selected from hydrogen and halo;

W is O, S, or NH;

R 4a and R 4b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 5a and R 5b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 6a and R 6b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 7 is hydrogen or fluoro; and

X is O, S, or NH;

or a salt, hydrate, solvate, or tautomer thereof.

2. The method of claim 1 , wherein:

R 1 is different from R 2 ; or

one of R 1 and R 2 carries a positive charge and the other carries a negative charge; or

R 1 is —NR 1a R 1b and R 2 is OR 1c .

3. The method of claim 1 , wherein:

one of R 1a and R 1b is C 1-20 alkyl and R 2 is OH; or

one of R 1a and R 1b is a polyamine and R 2 is OH; or

one of R 1a and R 1b is —(CH 2 ) n NH(CH 2 ) n NHR x , wherein R x is hydrogen or —(CH 2 ) n NH 2 and n is independently a number from 2 to 4; or

one of R 1a and R 1b is —(CH 2 ) n NHR x , wherein R x is hydrogen or —(CH 2 ) n NH 2 and n is independently a number from 2 to 4; or

one of R 1a and R 1b is —CH(R 1d )—C(O)OR 1e and R 2 is OH.

4. The method of claim 1 , wherein:

R 1d is selected from hydrogen, alkyl, substituted alkyl, heteroaryl, and substituted heteroaryl; or

R 1d is a positively charged amino acid side chain; or

—CH(R 1d )—C(O)OR 1e is an amino acid selected from lysine, arginine, and histidine.

5. The method of claim 1 , wherein:

R 3a and R 3b are hydrogen; or

one of R 3a and R 3b is halo.

6. The method of claim 1 , wherein W is O.

7. The method of claim 1 , wherein R 4a and R 4b are hydrogen.

8. The method of claim 1 , wherein one of R 5a and R 5b is —OH; or

one of R 5a and R 5b is selected from —NH 2 and N 3 ; or

one of R 5a and R 5b is —CH═CH 2 ; or

one of R 5a and R 5b is C 1-2 alkyl; or

one of R 5a and R 5b is C 1-2 alkyl, substituted with —OH, —NH 2 , or N 3 .

9. The method of claim 1 , wherein R 6a and R 6b are hydrogen.

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

11. The method of claim 1 , wherein R 7 is fluoro.

12. The method of claim 1 , wherein X is O.

13. The method of claim 1 , wherein the method is a method for inhibiting telomere elongation.

14. The method of claim 13 , wherein the cell is a cancer cell.

15. The method of claim 1 , wherein the method is a method for shortening telomere length.

16. A method for inhibiting telomere elongation or shortening telomere length, the method comprising:

contacting a cell or a tissue with a compound of formula (IV):

wherein

X 1 is NH or O;

X 2 is NH or O;

R 30 is hydrogen, optionally substituted C 1-20 alkyl, optionally substituted C 2-20 alkenyl, or optionally substituted C 2-20 alkynyl;

R 1 is selected from —NR 1a R 1b and OR 1c ; wherein

R 1a and R 1b are independently selected from hydrogen, optionally substituted C 1-20 alkyl, optionally substituted polyamine, and —CH(R 1d )—C(O)OR 1e , wherein

R 1d is selected from hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl, and substituted heteroarylalkyl; and

R 1e is hydrogen or C 1-6 alkyl;

R 1c is selected from hydrogen, alkyl, and aryl;

R 3a and R 3b are independently selected from hydrogen and halo;

W is O, S, or NH;

R 4a and R 4b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 5a and R 5b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 6a and R 6b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 7 is hydrogen or fluoro; and

X 3 is O, S, or NH;

or a salt, hydrate, solvate, or tautomer thereof.

17. The method of claim 16 , wherein X 1 and X 2 are O.

18. The method of claim 16 , wherein R 30 is C 1-20 alkyl.

19. The method of claim 16 , wherein:

R 1 carries a positive charge or a negative charge; or

R 1 is —NR 1a R 1b .

20. The method of claim 19 , wherein:

one of R 1a and R 1b is C 1-20 alkyl; or

one of R 1a and R 1b is a polyamine;

one of R 1a and R 1b is —(CH 2 ) n NH(CH 2 ) n NHR x , wherein R x is hydrogen or —(CH 2 ) n NH 2 and n is independently a number from 2 to 4;

one of R 1a and R 1b is —(CH 2 ) n NHR x , wherein R x is hydrogen or —(CH 2 ) n NH 2 and n is independently a number from 2 to 4; or

one of R 1a and R 1b is —CH(R 1d )—C(O)OR 1e .

21. The method of claim 16 , wherein:

R 1d is selected from hydrogen, alkyl, substituted alkyl, heteroaryl, and substituted heteroaryl; or

R 1d is a positively charged amino acid side chain; or

CH(R 1d )—C(O)OR 1e is an amino acid selected from lysine, arginine, and histidine.

22. The method of claim 16 , wherein:

R 3a and R 3b are hydrogen; or

one of R 3a and R 3b is halo.

23. The method of claim 16 , wherein W is O.

24. The method of claim 16 , wherein R 4a and R 4b are hydrogen.

25. The method of claim 16 , wherein:

one of R 5a and R 5b is —OH; or

one of R 5a and R 5b is selected from —NH 2 and N 3 ; or

one of R 5a and R 5b is —CH═CH 2 ; or

one of R 5a and R 5b is C 1-2 alkyl; or

one of R 5a and R 5b is C 1-2 alkyl, substituted with —OH, —NH 2 , or N 3 .

26. The method of claim 16 , wherein R 6a and R 6b are hydrogen.

27. The method of claim 16 , wherein R 7 is hydrogen.

28. The method of claim 16 , wherein R 7 is fluoro.

29. The method of claim 16 , wherein X is O.

30. The method of claim 16 , wherein the method is a method for inhibiting telomere elongation.

31. The method of claim 30 , wherein the cell is a cancer cell.

32. The method of claim 16 , wherein the method is a method for shortening telomere length.

33. A method for inhibiting telomere elongation or shortening telomere length, the method comprising contacting a cell with a compound of formula (VI):

wherein

R 1 and R 2 are independently —OCH(R 1b )OC(O)OR 1a ; wherein R 1a and R 1b are independently selected from hydrogen and C 1-5 alkyl;

R 3a and R 3b are independently selected from hydrogen and halo;

W is O, S, or NH;

R 4a and R 4b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 5a and R 5b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 6a and R 6b are independently selected from hydrogen, —OH, —NH 2 , N 3 , —CH═CH 2 , and optionally substituted C 1-2 alkyl, wherein alkyl is substituted with —OH, —NH 2 , N 3 , or halogen;

R 7 is hydrogen or fluoro; and

X is O, S, or NH;

or a salt, hydrate, solvate, or tautomer thereof.

34. The method of claim 33 , wherein the cell is a cancer cell.

Assignments (3)
PATENT SECURITY AGREEMENT Recorded Nov 20, 2025
From: GERON CORPORATION
To: BIOPHARMA CREDIT PLC, AS COLLATERAL AGENT
Reel/Frame 073679/0773 →
PATENT SECURITY AGREEMENT Recorded Nov 12, 2024
From: GERON CORPORATION
To: BIOPHARMA CREDIT PLC [COLLATERAL AGENT]
Reel/Frame 069341/0832 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 7, 2022
From: GRYAZNOV, SERGEI M.; PRUZAN, RONALD A.; PONGRACZ, KRISZTINA
To: GERON CORPORATION
Reel/Frame 061012/0384 →
Continuity (6)
Division 16784825 · Feb 7, 2020
Division 16016071 · Jun 22, 2018
Division 15419559 · Jan 30, 2017
Division 14366218
Provisional Application 61579575 · Dec 22, 2011
Related Publication 20220306660A1 · Sep 29, 2022
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