Pyridine carbamates and their use as GLUN2B receptor modulators

1. A compound of Formula (I):

or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein:

n is 0 or 1;

R 1 , when present, is H; or R 1 , together with R 2 and the carbon atoms to which they are attached, forms a phenyl ring;

R 2 , when not forming a phenyl ring with R 1 and the carbon atoms to which they are attached, is H or C 1 -C 6 alkyl;

R 3 is H, halogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, O—C 1 -C 6 alkyl, or O—C 1 -C 6 haloalkyl;

R 4a and R 4b are, each independent from the other, H or C 1 -C 6 alkyl;

R 5 is aryl which is optionally substituted with one, two, or three substituents each of which is independently halogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, or O—C 1 -C 6 haloalkyl; pyridinyl which is optionally substituted with one substituent which is C 1 -C 6 haloalkyl; or thienyl which is optionally substituted with one substituent which is halogen or C 1 -C 6 alkyl; and

R 6a and R 6b are, each independent from the other, H or C 1 -C 6 alkyl which is optionally substituted with one substituent which is a 4 to 6 membered heterocycloalkyl; or R 6a and R 6b together with the carbon atom to which they are attached form a C 3 -C 6 cycloalkyl ring or a 4 to 6 membered heterocycloalkyl ring.

2. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, having the structure of Formula (Ia):

3. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, having the structure of Formula (Ib):

4. The compound of claim 3 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 1 is H.

5. The compound of claim 3 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 1 together with R 2 and the atoms to which they are attached forms a phenyl ring.

6. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 2 is H or C 1 -C 6 alkyl.

7. The compound of claim 6 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 2 is —CH 3 or —CH(CH 3 ) 2 .

8. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 3 is H, F, —CH 3 , —CH 2 CH 3 , —CHF 2 , —CF 2 CH 3 , —OCH 3 , or —OCHF 2 .

9. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 4a and R 4b are both H; or R 4a is H and R 4b is C 1 -C 6 alkyl.

10. The compound of claim 9 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 4a is H and R 4b is —CH 3 .

11. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is

and wherein:

each of R 7 , R 8 , and R 9 is, independent from the others, H, halogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, or O—C 1 -C 6 haloalkyl.

12. The compound of claim 11 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein each of R 7 , R 8 , and R 9 is, independent from the others H, F, Cl, —CH 3 , —CHF 2 , —CF 2 CH 3 , —CF 3 , —OCHF 2 , or —OCF 3 .

13. The compound of claim 11 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is:

14. The compound of claim 1 or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is

15. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is

16. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 6a and R 6b are both H.

17. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein one of R 6a and R 6b is H and the other is C 1 -C 6 alkyl which is optionally substituted with one substituent which is a 4 to 6 membered heterocycloalkyl.

18. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein one of R 6a and R 6b is H and the other is —CH 3 , —CH(CH 3 ) 2 , or —CH 2 R 12 , where R 12 is 4 to 6 membered heterocycloalkyl.

19. The compound of claim 18 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 12 is

20. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 6a and R 6b are both C 1 -C 6 alkyl.

21. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 6a and R 6b together with the carbon atom to which they are attached form a cyclobutyl ring or a cyclopropyl ring.

22. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 6a and R 6b together with the carbon atom to which they are attached is:

wherein * denotes the point of attachment of the ring to the remainder of the molecule.

23. The compound of claim 2 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein:

R 2 is H or —CH 3 ;

R 3 is —CH 3 , —OCH 3 , or —OCHF 2 ;

R 4a and R 4b both H;

R 5 is

wherein each of R 7 , R 8 , and R 9 is, independent from the others, H, halogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, or O—C 1 -C 6 haloalkyl; and

R 6a and R 6b are both H.

24. The compound of claim 23 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is

25. The compound of claim 3 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein:

R 1 is H;

R 2 is H;

R 3 is H, F, or —CH 3 ;

R 4a and R 4b are both H;

R 5 is

wherein each of R 7 , R 8 , and R 9 is, independent from the others, H, halogen, C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, or O—C 1 -C 6 haloalkyl; and

R 6a and R 6b are both H.

26. The compound of claim 25 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein R 5 is

27. The compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein

R 1 , when present, is H;

R 2 is H;

R 3 is H or C 1 -C 3 alkyl;

R 4a and R 4b are both H; or R 4a is H and R 4b is C 1 -C 3 alkyl;

R 5 is

and

R 6a and R 6b are both H; or one of R 6a and R 6b is H and the other is C 1 -C 3 alkyl.

28. A compound, or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein the compound is

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

(4S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-isopropyl-oxazolidin-2-one;

1-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4H-3,1-benzoxazin-2-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

5-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-6,6-dimethyl-1,3-oxazinan-2-one;

(4R)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-isopropyl-oxazolidin-2-one;

6-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

6-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-2,8-dioxa-6-azaspiro[3.4]octan-7-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

2-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4,8-dioxa-2-azaspiro[4.5]decan-3-one;

6-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-2,6-diazaspiro[3.4]octan-7-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

(4S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-isopropyl-oxazolidin-2-one;

1-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4H-3,1-benzoxazin-2-one

(R/S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one

(R*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

5-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-6,6-dimethyl-1,3-oxazinan-2-one;

(4R)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-isopropyl-oxazolidin-2-one;

6-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

(5R)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

6-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-2,8-dioxa-6-azaspiro[3.4]octan-7-one;

(R/S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one

(S*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-isopropyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

(R/S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-(morpholinomethyl)oxazolidin-2-one;

2-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4,8-dioxa-2-azaspiro[4.5]decan-3-one;

6-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-2,6-diazaspiro[3.4]octan-7-one;

3-[[5-(4-Fluoro-3-methyl-phenyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(2,4-Difluoro-3-methyl-phenyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(Trifluoromethyl)phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[4-Chloro-3-(difluoromethoxy)phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-Fluoro-4-(trifluoromethoxy)phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(1,1-Difluoroethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[6-(Trifluoromethyl)-2-pyridyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[2-(Trifluoromethyl)-4-pyridyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[4-Fluoro-3-(trifluoromethyl)phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[4-chloro-3-(difluoromethoxy)phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl] oxazolidin-2-one;

3-[Dideuterio-[5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-[3-(difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-(4-fluoro-3-methyl-phenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

(R/S)-3-[1-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]ethyl]oxazolidin-2-one;

(R/S)-3-[1-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]ethyl]-1,3-oxazinan-2-one;

3-[[5-[3-(Difluoromethyl)phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[3-(Difluoromethoxy)phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3-Chlorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3-Chloro-4-fluoro-phenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(4-Fluoro-3-methyl-phenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3,4-Difluorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(4-Fluorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3-Fluorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3,4-Difluoro-5-methyl-phenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(2,4-Difluoro-3-methyl-phenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(2,4-Difluorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(3,4-Dichlorophenyl)-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[2-Methyl-5-[3-(Trifluoromethyl)phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one

3-[[5-[4-Fluoro-3-(trifluoromethyl)phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one

3-[[5-(4-Fluoro-3-methyl-phenyl)-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(2,4-Difluoro-3-methyl-phenyl)-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(1,1-Difluoroethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl] oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(R*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

5-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

6-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

(5R)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5,5-dimethyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[4-Chloro-3-(difluoromethoxy)phenyl]-2-methyl-3-pyridyl]methyl] oxazolidin-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl] oxazolidin-2-one;

6-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

(5R)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5,5-dimethyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(R/S)-3-[[5-[3-(difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

5-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-(5-Chloro-2-thienyl)-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-Methyl-5-[5-(trifluoromethyl)-2-thienyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[5-(Difluoromethyl)-2-thienyl]-2-methyl-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-Methoxy-5-[3-(trifluoromethyl)phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-Methoxy-5-(3,4,5-trifluorophenyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(2,4-Difluoro-3-methyl-phenyl)-2-methoxy-3-pyridyl]methyl] oxazolidin-2-one;

3-[[5-(3-Fluoro-5-methyl-phenyl)-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-Methoxy-5-(m-tolyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(3,4-Dichlorophenyl)-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[4-Chloro-3-(difluoromethoxy)phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(3-Chloro-4-fluoro-phenyl)-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(3-Chlorophenyl)-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(1,1-Difluoroethyl)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(1,1-Difluoroethyl)phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(3,4-Difluoro-5-methyl-phenyl)-2-methoxy-3-pyridyl]methyl] oxazolidin-2-one;

3-[[5-[4-Fluoro-3-(trifluoromethoxy)phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(2,5-Difluoro-3-methyl-phenyl)-2-methoxy-3-pyridyl]methyl] oxazolidin-2-one;

3-[[5-[4-Chloro-3-(difluoromethyl)phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-(4-Fluoro-3-methyl-phenyl)-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

(4S)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(4R)-3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl] oxazolidin-2-one;

(4S)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(4R)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methoxy-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-(Difluoromethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[2-(Difluoromethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-(difluoromethyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-2-(difluoromethyl)-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[2-(Difluoromethyl)-5-(4-fluoro-3-methyl-phenyl)-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[2-(Difluoromethyl)-5-(4-fluoro-3-methyl-phenyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[5-[4-Chloro-3-(difluoromethoxy)phenyl]-2-(difluoromethyl)-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[4-Chloro-3-(difluoromethoxy)phenyl]-2-(difluoromethyl)-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-(Difluoromethoxy)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

(4R)-3-[[2-(Difluoromethoxy)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

3-[[2-(Difluoromethoxy)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

(4R)-3-[[2-(Difluoromethoxy)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

6-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

(5R)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(5S)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

5-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

(4S)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(4R)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(4R)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

(4S)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-4-methyl-oxazolidin-2-one;

5-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-7-oxa-5-azaspiro[2.4]heptan-6-one;

6-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-8-oxa-6-azaspiro[3.4]octan-7-one;

(5S)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

(5R)-3-[[2-(1,1-Difluoroethyl)-5-[3-(difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

3-((5-(3-(Difluoromethoxy)-4-fluorophenyl)-2-fluoropyridin-3-yl)methyl)oxazolidin-2-one; or

3-((5-(3-(Difluoromethoxy)-4-fluorophenyl)-2-fluoropyridin-3-yl)methyl)-1,3-oxazinan-2-one.

29. A compound, or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, wherein the compound is

3-[[5-[3-(Difluoromethoxy)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]oxazolidin-2-one;

(S*)-3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-5-methyl-oxazolidin-2-one;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[[5-[4-chloro-3-(difluoromethoxy)phenyl]-3-pyridyl]methyl]-1,3-oxazinan-2-one;

3-[Dideuterio-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]methyl] oxazolidin-2-one;

(R/S)-3-[1-[5-[3-(difluoromethyl)-4-fluoro-phenyl]-3-pyridyl]ethyl]oxazolidin-2-one trifluoroacetate salt;

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl] oxazolidin-2-one; or

3-[[5-[3-(Difluoromethyl)-4-fluoro-phenyl]-2-methyl-3-pyridyl]methyl]-1,3-oxazinan-2-one.

30. A pharmaceutical composition comprising: (A) the compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof, and (B) at least one pharmaceutically acceptable excipient.

31. A method of treating a subject suffering from or diagnosed with a disease, disorder, or medical condition mediated by GluN2B receptor activity, comprising administering to the subject a therapeutically effective amount of the compound of claim 1 , or a pharmaceutically acceptable salt, solvate, isotopic variant, or N-oxide thereof.

32. The method of claim 31 , wherein the disease, disorder or medical condition mediated by GluN2B receptor activity comprises bipolar disorder, major depressive disorder, treatment-resistant depression, a mood disorder, post-partum depression, seasonal affective disorder, Alzheimer's disease, Parkinson's disease, Huntington's chorea, multiple sclerosis, cognitive impairment, head injury, spinal cord injury, stroke, epilepsy, dyskinesias, amyotrophic lateral sclerosis, neurodegeneration associated with a bacterial or chronic infection, pain, diabetic neuropathy, migraine, cerebral ischemia, schizophrenia, encephalitis, autism or an autism spectrum disorder, a memory disorder, a learning disorder, obsessive compulsive disorder, attention deficit hyperactivity disorder (ADHD) or an addictive illness.

33. The method of claim 32 , wherein the disease, disorder or medical condition mediated by GluN2B receptor activity comprises bipolar disorder, a mood disorder, treatment resistant depression, major depressive disorder, or epilepsy.