Potassium channel inhibitors

1. A compound of formula I,

or a pharmaceutically acceptable salt, or an optical isomer thereof, wherein:

A is

a heteroaryl ring, wherein the point of attachment to the heteroaryl ring is a carbon atom, and the heteroaryl ring is

a 6-membered unsaturated monocyclic ring with 1 N and 5 carbon atoms and three double bonds,

said heteroaryl ring is unsubstituted, mono-substituted with R 4 , disubstituted with groups independently selected from R 4 , trisubstituted with groups independently selected from R 4 , or tetrasubstituted with groups independently selected from R 4 ;

B is a heteroaryl ring, wherein the point of attachment to the heteroaryl ring is a carbon atom or a nitrogen atom, and wherein the heteroaryl ring is

a 6-membered unsaturated monocyclic ring with 1 N and 5 carbon atoms and three double bonds,

said heteroaryl ring is unsubstituted, mono-substituted with R 4 , disubstituted with groups independently selected from R 4 , trisubstituted with groups independently selected from R 4 , or tetrasubstituted with groups independently selected from R 4 ;

C is a phenyl ring, wherein

said phenyl ring is unsubstituted, mono-substituted with R 4 , disubstituted with groups independently selected from R 4 , trisubstituted with groups independently selected from R 4 , or tetrasubstituted with groups independently selected from R 4 ;

D is —NH-A 1 , wherein A 1 is a monocyclic unsaturated ring containing one N atom and 5 carbon atoms in the ring and three double bonds;

X is H, F, C 1-6 alkyl, CF 3 and CN;

Y is selected from the group consisting of H, F, C 1-6 alkyl, CN, and CF 3 ;

Z is selected from the group consisting of H, OR 5 , NR 5 R 5 , F, CN, S(O) 0-2 R 5 , C(O)OR 5 , and C(O)N(R 5 ) 2 ;

R a , in each instance in which it appears, is independently selected from the group consisting of

1) hydrogen,

2) C 1 -C 6 alkyl,

3) halogen,

4) aryl,

5) heterocycle,

6) C 3 -C 10 cycloalkyl,

7) OR 5 , and

8) CH 2 OR 5 ,

said alkyl, aryl, heterocycle and cycloalkyl is unsubstituted or substituted with at least one substituent selected from R 6 ;

R 4 , in each instance in which it appears, is independently selected from the group consisting of

1) hydrogen,

2) halogen,

3) NO 2 ,

4) CN,

5) CR 4 ═C(R 5 ) 2 ,

6) C≡CR 5 ,

7) (CR a 2 ) n OR 5 ,

8) (CR a 2 ) n N(R 5 ) 2 ,

9) (CR a 2 ) n C(O)R 5 ,

10) (CR a 2 ) n C(O)OR 5 ,

11) (CR a 2 ) n R 5 ,

12) (CR a 2 ) n S(O) m R 5 ,

13) (CR a 2 ) n S(O) m N(R 5 ) 2 ,

14) OS(O) m R 5 ,

15) N(R 5 )C(O)R 5 ,

16) N(R 5 )S(O) m R 5 ,

17) (CR a 2 ) n N(R 6 )R 5 ,

18) (CR a 2 ) n N(R 5 )(CR a 2 ) n C(O)N(R 5 ) 2 ,

19) (CR a 2 ) n N(R 5 )(CR a 2 ) n C(O)OR 5 ,

20) N(R 5 )(CR a 2 ) n R 5 ,

21) N(R 5 )(CR a 2 ) n N(R 5 ) 2 ,

22) (CR a 2 ) n C(O)N(R 5 ) 2 ,

23) (CR a 2 ) n C(O)NH(CR a 2 ) n R 5 ,

24) (CR a 2 ) n C(O)NHC(R 5 ) 2 (CR a 2 ) n N(R 5 ) 2 and

25) C(O)NH(CR a 2 )(CR a 3 );

R 5 , in each instance in which it appears, is independently selected from the group consisting of

1) hydrogen,

2) unsubstituted or substituted C 1 -C 6 alkyl,

3) unsubstituted or substituted C 3 -C 10 cycloalkyl,

4) unsubstituted or substituted aryl,

5) unsubstituted or substituted heterocycle,

6) CF 3 ,

7) unsubstituted or substituted C 2 -C 6 alkenyl, and

8) unsubstituted or substituted C 2 -C 6 alkynyl,

or in the case where R 5 is attached to a nitrogen atom that is disubstituted with R 5 , each R 5 is independently selected from C 1 -C 6 alkyl, and the nitrogen atom together with each R 5 form a ring;

R 6 , in each instance in which it appears, is independently selected from the group consisting of

1) hydrogen,

2) unsubstituted or substituted C 1 -C 6 alkyl,

3) halogen,

4) OR 5 ,

5) CF 3 ,

6) unsubstituted or substituted aryl,

7) unsubstituted or substituted C 3 -C 10 cycloalkyl,

8) unsubstituted or substituted heterocycle,

9) S(O) m N(R 5 ) 2 ,

10) C(O)OR 5 ,

11) C(O)R 5 ,

12) CN,

13) C(O)N(R 5 ) 2 ,

14) N(R 5 )C(O)R 5 ,

15) N(R 5 )C(O)OR 5 ,

16) N(R 5 )C(O)N(R 5 ) 2 ,

17) OC(O)N(R 5 ) 2 ,

18) S(O) m R 5 ,

19) OS(O) m R 5 ,

20) NO 2 ,

21) N(R 5 ) 2 ;

22) SC(O)R 5 ,

23) N(R 5 )S(O) m R 5 ,

m is independently 0, 1 or 2; and

n, in each instance in which it occurs, is independently selected from 0, 1, 2, 3, 4, 5 or 6.

2. A compound of claim 1 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, wherein:

Z is H or —OH.

3. A compound of claim 2 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, wherein

B is selected from the group consisting of

4. A compound of claim 3 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, wherein

A is

5. A compound of claim 4 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, wherein

C-D is

6. A compound of claim 5 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, wherein D is selected from the group consisting of hydrogen,

7. A compound of claim 6 , or a pharmaceutically acceptable salt thereof, or an optical isomer thereof, selected from the group consisting of

N-[2-(2,2-dipyridin-3-ylethyl)phenyl]pyridin-2-amine,

N-(6-{[2-(2,2-dipyridin-3-ylethyl)phenyl]amino}pyridin-2-yl)methanesulfonamide,

N-[2-(2,2-dipyridin-3-ylethyl)phenyl]pyridin-3-amine,

N-[2-(2,2-dipyridin-3-ylethyl)phenyl]pyridin-4-amine,

N 2 -[2-(2,2-dipyridin-3-ylethyl)phenyl]pyridine-2,5-diamine,

6-{[2-(2,2-dipyridin-3-ylethyl)phenyl]amino}nicotinonitrile,

2-{[2-(2,2-dipyridin-3-ylethyl)phenyl]amino}nicotinonitrile,

6-{[2-(2,2-dipyridin-3-ylethyl)phenyl]amino}pyridine-2-carbonitrile,

N-[3-(2,2-dipyridin-3-ylethyl)phenyl]pyridin-2-amine,

N-[3-(2,2-dipyridin-3-ylethyl)phenyl]pyridin-3-amine, and

N-[2-(2,2-dipyridin-3-ylethyl)-5-fluorophenyl]pyridin-3-amine.

8. A pharmaceutical formulation comprising a pharmaceutically acceptable carrier and the compound of Formula (I) according to claim 1 or a pharmaceutically acceptable crystal form or hydrate thereof.