N-aryl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide herbicides

• US 5,571,775 A
• Filed: 06/06/1995
• Issued: 11/05/1996
• Est. Priority Date: 07/11/1994
• Status: Expired due to Fees

• Current Assignee: DowElanco Co. (Corteva, Inc.)
• Original Assignee: DowElanco Co. (Corteva, Inc.)
• Inventors: Bradley, Kimberly B., Benk o, Zolt an, Ehr, Robert J., Arndt, Kim E., Van Heertum, John C., Kleschick, William A., Costales, Mark J., Jachetta, John J., Reifschneider, Walter
• Primary Examiner(s): Chang, Ceila
• Assistant Examiner(s): HUANG, EVELYN MEI
• Application Number:
  US08/466,510
• Time in Patent Office: 518 Days
• Field of Search: 546/119, 504/246
• US Class Current: 504/246
• CPC Class Codes: A01N 43/90 having two or more relevant hetero rings, condensed among themselves or with a common carbocyclic ring system
• CPC Class Codes: C07D 471/04 Ortho-condensed systems

Abstract

Substituted N-aryl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide compounds, such as N-(2,6-difluorophenyl)-5-methoxy-7-methyl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide, N-(4-bromo-1-methyl-3-pyrazoly)-8-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide, and N-(2-fluoro-4-methyl-3-pyridinyl)-8-ethoxy-6-chloro[1,2,4]triazolo[1,5-a]-pyridine-2-sulfonamide, were prepared by condensation of a 2-chlorosulfonyl[1,2,4]triazolo[1,5-a]pyridine compound with an aryl amine. The compounds prepared were found to possess excellent herbicidal activity on a broad spectrum of vegetation at low application rates.

Claims

1. An N-aryl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide compound of the formula:

##STR13## wherein W, X, Y, and Z each independently represents H, CH₃, CH₂ CH₃, CH₂ OCH₃, CF₃, F, Cl, Br, I, OCH₂ CF₃, S(C₁ -C₃)alkyl, or O(C₁ -C₃)alkyl optionally monosubstituted with F, Cl, or OCH₃, with the proviso that at least one of W, X, Y, and Z represents H;

V represents H, COR'"'"', CO₂ R", or CONR'"'"'"₂ ;

Ar represents an aromatic moiety one of the formulas;

##STR14## A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ;

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H;

A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ;

A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position;

B" represents H when the point of attachment is the 3-or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position;

T represents H or F;

n represents 0, 1, or 2;

R'"'"' represents (C₁ -C₄)alkyl optionally singly to completely substituted with fluorine;

R" represents (C₁ -C₄)alkyl, (C₃ -C₄)alkenyl, or (C₃ -C₄)alkynyl;

R'"'"'" represents H or (C₁ -C₄)alkyl; and

when V represents H, the agriculturally acceptable salts thereof.

2. A compound according to claim 1 wherein V represents H or an agriculturally acceptable salt thereof.

3. A compound according to claim 1 wherein two of W, X, Y, and Z represent H.

4. A compound according to claim 1 wherein one or both of W and Z represents OCH₃ or wherein W represents OCH₂ CH₃ or OC₃ H₇ (i).

5. A compound according to claim 4 wherein W represents methoxy, ethoxy, or isopropoxy, X and Z each represent hydrogen, and Y represents methyl or a halogen;

or wherein W represents methoxy or ethoxy, X and Y each represent hydrogen, and Z represents methyl, methoxy, or a halogen;

or wherein Z represents methoxy or ethoxy, W and Y each represent hydrogen, and X represents methyl, trifluoromethyl, or a halogen.

6. A compound according to claim 1 wherein Ar represents:

##STR15## wherein A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ; and

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H.

7. A compound according to claim 6 wherein A represents F, Cl, Br, CF₃, NO₂, or CO₂ CH₃ ;

B represents F, Cl, Br, OCH₃, or CH₃, and J represents H; and

D represents H or CH₃.

8. A compound according to claim 1 wherein Ar represents:

##STR16## wherein A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ; and

n represents 0, 1, or 2.

9. A compound according to claim 8 wherein A'"'"' represents CH₃, O(C₁ -C₃)alkyl, F, Cl, Br, or I;

B'"'"' represents F, Cl, Br, I, CH₃, C₂ H₅, CF₃, O(C₁ -C₃)alkyl, OCH(CH₃)CF₃, OCH₂ CH₂ F, OCH₂ CHF₂, or CO₂ (C₁ -C₃)alkyl; and

D'"'"' represents H.

10. A compound according to claim 9 wherein A'"'"' represents Br, Cl, F, or OCH₃, B'"'"' represents CH₃, OCH₃, OC₂ H₅, OC₃ H₇ (n), OC₃ H₇ (i), OCH(CH₃)CF₃, or OCH₂ CH₂ F, and D'"'"' represents H;

or wherein A'"'"' represents OCH₃ or OC₂ H₅, B'"'"' represents CO₂ (C₁ -C₂)alkyl, Br, Cl, or F, and D'"'"' represents H.

11. A compound according to claim 1 wherein Ar represents:

##STR17## wherein A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position; and

B" represents H when the point of attachment is the 3- or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position.

12. A compound according to claim 11 wherein A" represents Cl, Br, I, or CF₃ and B" represents H.

13. A compound according to claim 1 wherein Ar represents:

##STR18## wherein T represents H or F.

14. A compound according to claim 13 wherein T represents 4-F.

15. A compound according to claim 1 which is N-(4-bromo-1-methyl-3-pyrazolyl)-8-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

16. A compound according to claim 1 which is N-(2,6-dichlorophenyl)-6-bromo-8-methoxy[1,2,4]triazolo1,5-a]pyridine-2-sulfonamide.

17. A compound according to claim 1 which is N-(2,6-difluorophenyl)-8-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

18. A compound according to claim 1 which is N-(2-fluoro-4-methyl-3-pyridinyl)-7-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

19. A compound according to claim 1 which is N-(2-chloro-4-methyl-3-pyridinyl)-5-methoxy-7-methyl1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

20. An herbicidal composition comprising an agriculturally acceptable adjuvant or carrier and an herbicidally effective amount of an N-aryl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide compound of the formula:

##STR19## wherein W, X, Y, and Z each independently represents H, CH₃, CH₂ CH₃, CH₂ OCH₃, CF₃, F, Cl, Br, I, OCH₂ CF₃, S(C₁ -C₃)alkyl, or O(C₁ -C₃)alkyl optionally monosubstituted with F, Cl, or OCH₃ with the proviso that at least one of W, X, Y, and Z represents H;

V represents H, COR'"'"', CO₂ R", or CONR'"'"'"₂ ;

Ar represents an aromatic moiety one of the formulas;

##STR20## A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ;

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H;

A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ;

A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position;

B" represents H when the point of attachment is the 3- or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position;

T represents H or F;

n represents 0, 1, or 2;

R'"'"' represents (C₁ -C₄)alkyl optionally singly to completely substituted with fluorine;

R" represents (C₁ -C₄)alkyl, (C₃ -C₄)alkenyl, or (C₃ -C₄)alkynyl;

R'"'"'" represents H or (C₁ -C₄)alkyl; and

when V represents H, the agriculturally acceptable salts thereof.

21. A composition according to claim 20 wherein V represents H or an agriculturally acceptable salt thereof.

22. A composition according to claim 20 wherein two of W, X, Y, and Z represent H.

23. A composition according to claim 20 wherein one or both of W and Z represents OCH₃ or wherein W represents OCH₂ CH₃ or OC₃ H₇ (i).

24. A composition according to claim 23 wherein W represents methoxy, ethoxy, or isopropoxy, X and Z each represent hydrogen, and Y represents methyl or a halogen;

or wherein W represents methoxy or ethoxy, X and Y each represent hydrogen, and Z represents methyl, methoxy, or a halogen;

or wherein Z represents methoxy or ethoxy, W and Y each represent hydrogen, and X represents methyl, trifluoromethyl, or a halogen.

25. A composition according to claim 20 wherein Ar represents:

##STR21## wherein A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ; and

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H.

26. A composition according to claim 25 wherein A represents F, Cl, Br, CF₃, NO₂, or CO₂ CH₃ ;

B represents F, Cl, Br, OCH₃, or CH₃, and J represents H; and

D represents H or CH₃.

27. A composition according to claim 20 wherein Ar represents:

##STR22## wherein A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ; and

n represents 0, 1, or 2.

28. A composition according to claim 27 wherein A'"'"' represents CH₃, O(C₁ -C₃)alkyl, F, Cl, Br, or I;

B'"'"' represents F, Cl, Br, I, CH₃, C₂ H₅, CF₃, O(C₁ -C₃)alkyl, OCH(CH₃)CF₃, OCH₂ CH₂ F, OCH₂ CHF₂, or CO₂ (C₁ -C₃)alkyl; and

D'"'"' represents H.

29. A composition according to claim 28 wherein A'"'"' represents Br, Cl, F, or OCH₃, B'"'"' represents CH₃, OCH₃, OC₂ H₅, OC₃ H₇ (n), OC₃ H₇ (i), OCH(CH₃)CF₃, or OCH₂ CH₂ F, and D'"'"' represents H;

or wherein A'"'"' represents OCH₃ or OC₂ H₅, B'"'"' represents CO₂ (C₁ -C₂)alkyl, Br, Cl, or F, and D'"'"' represents H.

30. A composition according to claim 20 wherein Ar represents:

##STR23## A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position; and

B" represents H when the point of attachment is the 3- or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position.

31. A composition according to claim 30 wherein A" represents Cl, Br, I, or CF₃ and B" represents H.

32. A composition according to claim 20 wherein Ar represents:

##STR24## wherein T represents H or F.

33. A composition according to claim 32 wherein T represents 4-F.

34. A composition according to claim 20 wherein the compound is N-(4-bromo-1-methyl-3-pyrazolyl)-8-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

35. A composition according to claim 20 wherein the compound is N-(2,6-dichlorophenyl)-6-bromo-8-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

36. A composition according to claim 20 wherein the compound is N-(2,6-difluorophenyl)-8-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

37. A composition according to claim 20 wherein the compound is N-(2-fluoro-4-methyl-3-pyridinyl)-7-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

38. A composition according to claim 20 wherein the compound is N-(2-chloro-4-methyl-3-pyridinyl)-5-methoxy-7-methyl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

39. A method of controlling undesirable vegetation which comprises applying to said vegetation or to the locus thereof an herbicidally effective amount of an N-aryl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide compound of the formula:

##STR25## wherein W, X, Y, and Z each independently represents H, CH₃, CH₂ CH₃, CH₂ OCH₃, CF₃, F, Cl, Br, I, OCH₂ CF₃, S(C₁ -C₃)alkyl, or O(C₁ -C₃)alkyl optionally monosubstituted with F, Cl, or OCH₃ with the proviso that at least one of W, X, Y, and Z represents H;

V represents H, COR'"'"', CO₂ R", or CONR'"'"'"₂ ;

Ar represents an aromatic moiety one of the formulas;

##STR26## A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ;

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H;

A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ;

A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position;

B" represents H when the point of attachment is the 3- or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position;

T represents H or F;

n represents 0, 1, or 2;

R'"'"' represents (C₁ -C₄)alkyl optionally singly to completely substituted with fluorine;

R" represents (C₁ -C₄)alkyl, (C₃ -C₄)alkenyl, or (C₃ -C₄)alkynyl;

R'"'"'" represents H or (C₁ -C₄)alkyl; and

when V represents H, the agriculturally acceptable salts thereof.

40. A method according to claim 39 wherein V represents H or an agriculturally acceptable salt thereof.

41. A method according to claim 39 wherein two or three of W, X, Y, and Z represent H.

42. A method according to claim 39 wherein one or both of W and Z represents OCH₃ or wherein w represents OCH₂ CH₃ or OC₃ H₇ (i).

43. A method according to claim 42 wherein W represents methoxy, ethoxy, or isopropoxy, X and Z each represent hydrogen, and Y represents methyl or a halogen;

or wherein W represents methoxy or ethoxy, X and Y each represent hydrogen, and Z represents methyl, methoxy, or a halogen;

or wherein Z represents methoxy or ethoxy, W and Y each represent hydrogen, and X represents methyl, trifluoromethyl, or a halogen.

44. A method according to claim 39 wherein Ar represents:

##STR27## wherein A represents F, Cl, Br, CO₂ R", CONR'"'"'"₂, (C₁ -C₂)haloalkyl, NO₂, CN, SOR'"'"', or SO₂ R'"'"';

B represents H, CH₃, C₂ H₅, F, Cl, Br, CN, OR'"'"', SR'"'"', NR'"'"'"₂, phenyl, or phenoxy, each phenyl and phenoxy optionally possessing 1 to 3 substituents selected from the group consisting of F, Cl, Br, CN, CF₃, NO₂, and CH₃ ; and

D and J each independently represents H or CH₃ with the proviso that at least one of D and J represents H.

45. A method according to claim 44 wherein A represents F, Cl, Br, CF₃, NO₂, or CO₂ CH₃ ;

B represents F, Cl, Br, OCH₃, or CH₃, and J represents H; and

D represents H or CH₃.

46. A method according to claim 39 wherein Ar represents:

##STR28## wherein A'"'"' and B'"'"' each independently represents H, R'"'"', OR'"'"', OCH₂ CH₂ Cl, OCH₂ CH₂ OCH₃, S(O)_n R'"'"', F, Cl, Br, I, CN, NO₂, C₆ H₅, CO₂ R", or CONR'"'"'"₂ with the proviso that not more than one of A'"'"' and B'"'"' represents H;

D'"'"' represents H, F, Cl, Br, I, CF₃, or CH₃ ; and

n represents 0, 1, or 2.

47. A method according to claim 46 wherein A'"'"' represents CH₃, O(C₁ -C₃)alkyl, F, Cl, Br, or I;

B'"'"' represents F, Cl, Br, I, CH₃, C₂ H₅, CF₃, O(C₁ -C₃)alkyl, OCH(CH₃)CF₃, OCH₂ CH₂ F, OCH₂ CHF₂, or CO₂ (C₁ -C₃)alkyl; and

D'"'"' represents H.

48. A method according to claim 47 wherein A'"'"' represents Br, Cl, F, or OCH₃, B'"'"' represents CH₃, OCH₃, OC₂ H₅, OC₃ H₇ (n), OC₃ H₇ (i), OCH(CH₃)CF₃, or OCH₂ CH₂ F, and D'"'"' represents H;

or wherein A'"'"' represents OCH₃ or OC₂ H₅, B'"'"' represents CO₂ (C₁ -C₂)alkyl, Br, Cl, or F, and D'"'"' represents H.

49. A method according to claim 39 wherein Ar represents:

##STR29## A" represents F, Cl, Br, I, CF₃, SCF₃, CN, CO₂ R", or CONR'"'"'"₂ and is located in the 4-position when the point of attachment is the 3- or 5-position and represents F, Cl, Br, I, CF₃, or CH₃ and is located in the 3- or 5-position when the point of attachment is the 4-position; and

B" represents H when the point of attachment is the 3- or 5-position and represents H, Cl, Br, F, CH₃, or OCH₃ and is located the 3- or 5-position not occupied by A" when the point of attachment is the 4-position.

50. A method according to claim 49 wherein A" represents Cl, Br, I, or CF₃ and B" represents H.

51. A method according to claim 39 wherein Ar represents:

##STR30## wherein T represents H or F.

52. A method according to claim 51 wherein T represents 4-F.

53. A method according to claim 39 wherein the compound is N-(4-bromo-1-methyl-3-pyrazolyl)-8-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

54. A method according to claim 39 wherein the compound is N-(2,6-dichlorophenyl)-6-bromo-8-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

55. A method according to claim 39 wherein the compound is N-(2,6-difluorophenyl)-8-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

56. A method according to claim 39 wherein the compound is N-(2-fluoro-4-methyl-3-pyridinyl)-7-chloro-5-methoxy[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.

57. A method according to claim 39 wherein the compound is N-(2-chloro-4-methyl-3-pyridinyl)-5-methoxy-7--methyl[1,2,4]triazolo[1,5-a]pyridine-2-sulfonamide.