Inhibitors of the plasmodial surface anion channel as antimalarials

1. A method of providing prophylaxis to an animal against malaria or treating an animal afflicted with malaria comprising administering to the animal:

(i) an effective amount of a compound of formula I:

wherein R 1 is hydrogen or alkyl and R 2 is arylalkyl, optionally substituted on the aryl with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl; or R 2 is a group of formula (II):

wherein n=0 to 6;

or R 1 and R 2 together with the N to which they are attached form a heterocycle of formula III:

wherein X is N or CH; and

Y is aryl, alkylaryl, dialkylaryl, arylalkyl, alkoxyaryl, or heterocyclic, optionally substituted with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl; and

R 3 -R 10 are hydrogen or alkyl; or a pharmaceutically acceptable salt thereof.

2. The method of claim 1 , wherein R 3 in formula I is hydrogen.

3. The method of claim 1 , wherein R 4 -R 7 in formula I are hydrogen.

4. The method of claim 1 , wherein R 1 in formula I is hydrogen or alkyl and R 2 is a group of formula II, wherein n=1 to 6.

5. The method of claim 4 , wherein n=2 to 4.

6. The method of claim 1 , wherein R I and R 2 together with the N to which they are attached form a heterocycle of formula III.

7. The method of claim 1 , wherein X in formula III is N.

8. The method of claim 7 , wherein in formula III, Y is aryl which is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, alkoxy, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl.

9. The method of claim 8 , wherein in formula III, Y is phenyl, which is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, alkoxy, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl.

10. The method of claim 9 , wherein Y is phenyl or phenyl substituted with one or more substituents selected from the group consisting of methyl, chloro, fluoro, and methoxy.

11. The method of claim 1 , wherein the compound of formula I is:

12. The method of claim 1 , wherein X in formula III is CH.

13. The method of claim 12 , wherein Y is arylalkyl or heterocyclic, which is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl.

14. The method of claim 13 , Y is benzyl or piperidinyl, which is optionally substituted with one or more substituents selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, aminoalkyl, alkylamino, alkylcarbonyl, alkoxycarbonyl, aminocarbonyl, and formyl.

15. The method of claim 12 , wherein the compound of formula I is:

16. The method of claim 1 , wherein R 1 in formula I is hydrogen and R 2 is arylalkyl, optionally substituted on the aryl with a substituent selected from the group consisting of halo, hydroxyl, nitro, cyano, amino, alkyl, aminoalkyl, alkylamino, alkylcarbonyl, and formyl.

17. The method of claim 16 , wherein R 2 is arylalkyl.

18. The method of claim 17 , wherein R 2 is phenylalkyl.

19. The method of claim 18 , wherein the phenylalkyl is phenylbutyl.

20. The method of claim 19 , wherein the compound of formula I is:

21. The method of claim 5 , wherein the compound of formula II is:

22. The method of claim 1 , wherein said animal is a human.