Modulators of cystic fibrosis transmembrane conductance regulator

1. A compound of formula I or formula II:

or a pharmaceutically acceptable salt thereof, wherein:

each R X is independently hydrogen, halo, CF 3 , C 1 -C 4 alkyl, or —OC 1 -C 4 alkyl; provided that both R X are not simultaneously hydrogen; or

the two R X , taken together form ring (a):

X is CH 2 , CF 2 , CH 2 —CH 2 , or CF 2 —CF 2 ;

ring A is 3-7 membered monocyclic cycloalkyl ring;

R AA and R BB , taken together with the nitrogen atom, form a pyrrolidinyl ring substituted with OR′;

R′ is hydrogen or C 1 -C 6 aliphatic, wherein up to two carbon units of said aliphatic are optionally and independently replaced by —CO—, —CS—, —COCO—, —CONR—, —CONRNR—, —CO 2 —, —OCO—, —NRCO 2 —, —O—, —NRCONR—, —OCONR—, —NRNR, —NRNRCO—, —NRCO—, —S—, —SO, —SO 2 —, —NR—, —SO 2 NR—, NRSO 2 —, or —NRSO 2 NR—;

R is hydrogen or C 1 -C 6 aliphatic;

Z is halo, CN, COOH, CF 3 , or difluoromethylenedioxy; and

q is 0-3.

2. The compound according to claim 1 , wherein two R X taken together form ring (a) and X is CH 2 .

3. The compound according to claim 1 , wherein two R X taken together form ring (a) and X is CF 2 .

4. The compound according to claim 1 , wherein one R X is hydrogen and the other R X is halo, CF 3 , C 1 -C 4 alkyl, or —OC 1 -C 4 alkyl.

5. The compound according to claim 1 , wherein one R X is hydrogen and the other R X is 4-methoxy.

6. The compound according to any one of claims 1 - 5 , wherein ring A is cyclopropyl, cyclopentyl, or cyclohexyl.

7. The compound according to claim 6 , wherein ring A is cyclopropyl or cyclopentyl.

8. The compound according to claim 6 , wherein ring A is cyclopropyl.

9. The compound according to claim 1 wherein R′ is hydrogen.

10. The compound according to claim 1 , wherein R′ is C 1-6 alkyl.

11. The compound according to claim 1 , wherein R AA and R BB , taken together, form a pyrrolidinyl with an OH substituent.

12. The compound according to claim 1 , wherein Z is selected from halo, CF 3 , or difluoromethylenedioxy.

13. The compound according to claim 1 , wherein q is 0.

14. The compound according to claim 1 , wherein q is 1.

15. The compound according to claim 1 , wherein R is hydrogen.

16. The compound according to claim 1 , wherein compounds of formula I or formula II comprise one or more, and preferably all, of the following features:

two R X taken together form ring (a);

X is CH 2 ;

ring A is cyclopropyl;

R is hydrogen;

q is 1; and

Z is halo, CF 3 , or difluoromethylenedioxy.

17. The compound according to claim 1 , wherein R AA and R BB in formula I, taken together with the nitrogen atom, form the following ring (i):

18. The compound according to claim 1 , wherein R AA and R BB in formula I, taken together with the nitrogen atom, form the following ring (ii):

19. A compound selected from

20. A pharmaceutical composition comprising:

(i) a compound according to claim 1 or 19 ; and

(ii) a pharmaceutically acceptable carrier.

21. The composition of claim 20 , optionally further comprising a CFTR potentiator.

22. A kit for use in measuring the activity of CFTR or a fragment thereof in a biological sample in vitro or in vivo, comprising:

(i) a first composition comprising a compound according to claim 1 ; and

(ii) instructions for:

a) contacting the composition with the biological sample;

b) measuring activity of said CFTR or a fragment thereof.

23. The kit according to claim 22 , further comprising instructions for

a) contacting an additional composition with the biological sample;

b) measuring the activity of said CFTR or a fragment thereof in the presence of said additional composition, and

c) comparing the activity of the CFTR in the presence of the additional composition with the density of the CFTR in the presence of said first composition.

24. The kit according to claim 23 , wherein the kit is used to measure the density of CFTR.

25. A compound of formula I′ or formula II′:

wherein:

R X is independently hydrogen, halo, CF 3 , C 1 -C a alkyl, or —OC 1 -C 4 alkyl; provided that both R X are not simultaneously hydrogen; or

the two R X , taken together form ring (a):

X is CH 2 , CF 2 , CH 2 —CH 2 , or CF 2 —CF 2 ;

ring A is 3-7 membered monocyclic cycloalkyl ring;

Z is halo, CN, COOH, CF 3 , or difluoromethylenedioxy;

q is 0-3;

L is a linker selected from C(O) or SO 2 ;

p is 0 or 1;

R is H or C 1 -C 6 aliphatic; and

CA is a suitable chiral auxiliary, wherein CA, L, p, and the oxygen atom linked thereto, taken together, is (+)-10-camphorsulfonate, (1S,4R)-(−)-ω-camphanic ester, (1R,2S,5R)-(−) mentholcarbonate, (1S,2R,5S)-(+)-mentholcarbonate, (1R,2R)-1-phenyl-2-cyclopropylester, or (3R)-tetrahydrofuran-3-carbonate.