Thienopyrimidinone NMDA receptor modulators and uses thereof

1. A method of treating a neurological disorder selected from schizophrenia, depression, an autism spectrum disorder, and Rett syndrome in a patient in need thereof, comprising administering to the patient an effective amount of a compound represented by Formula I:

and pharmaceutically acceptable salts, stereoisomers and prodrugs thereof, wherein:

R 1 and R 2 , together with the nitrogen to which they are attached, form a 4-6 membered heterocyclic ring substituted on a carbon not adjacent to the nitrogen by one, two or more substituents each independently selected from the group consisting of halogen, cyano, oxo, hydroxyl and C 1-6 alkyl (optionally substituted by one, two or three halogens);

R 3 is selected from the group consisting of phenyl, naphthyl, heteroaryl, heterocyclyl and C 3-6 cycloalkyl; wherein R 3 may optionally be substituted with one, two or three substituents each independently selected from C 1-4 alkyl, halogen, hydroxyl, cyano, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, C 1-6 alkylcarbonyl, R a R b N—SO 2 —, NR a R b , C(O)OH, C 1-4 alkoxycarbonyl, and NR a R b carbonyl; and wherein C 1-4 alkyl, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, and C 1-6 alkylcarbonyl may be optionally substituted by one or more substituents each independently selected from halogen, hydroxyl, cyano, and NR a R b ;

R 66 and R 67 are each independently selected from the group consisting of hydrogen, halogen, C 1-4 alkyl (optionally substituted by one, two, three substituents selected from halogen, hydroxyl, cyano and NR a R b ), and phenyl (optionally substituted by one, two or three halogens); and

R a and R b are independently selected, for each occurrence, from the group consisting of hydrogen, hydroxyl, and C 1-3 alkyl; or R a and R b , together with the nitrogen to which they are attached, form a 4-6 membered heterocyclic ring which may have an additional heteroatom selected from O, S, or N.

2. The method of claim 1 , wherein R 3 is selected from the group consisting of phenyl and heteroaryl; wherein R 3 is optionally substituted with one, two or three substituents each independently selected from the group consisting of C 1-4 alkyl, halogen, hydroxyl, cyano, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, C 1-6 alkylcarbonyl, R a R b N—SO 2 —, NR a R b , C(O)OH, C 1-4 alkoxycarbonyl, and NR a R b carbonyl; wherein C 1-4 alkyl, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, and C 1-6 alkylcarbonyl may be optionally substituted by one or more substituents each independently selected from halogen, hydroxyl, cyano, and NR a R b .

3. The method of claim 1 , represented by:

wherein

R 55 is selected from the group consisting of hydroxyl, fluorine, methyl, CF 3 , phenyl and hydroxyl; and wherein p is 1 or 2.

4. The method of claim 1 , represented by:

wherein

R 55 is selected from the group consisting of hydroxyl, fluorine, methyl, CF 3 , phenyl and hydroxyl; and wherein p is 1 or 2.

5. The method of claim 1 , wherein R 3 is phenyl, pyrimidinyl or pyridinyl, each optionally substituted by one or two substituents each independently selected from halogen and C 1-3 alkyl (optionally substituted by one, two or three halogens).

6. The method of claim 5 , represented by:

wherein

R 33 is selected from the group consisting of fluorine, chlorine, CF 3 and methyl; and wherein q is 0, 1, 2 or 3.

7. The method of claim 1 , wherein the neurological disorder is selected from schizophrenia, depression, an autism spectrum disorder, and Rett syndrome.

8. A method of treating a neurological disorder selected from schizophrenia, depression, an autism spectrum disorder, and Rett syndrome in a patient in need thereof, comprising administering to the patient an effective amount of a compound selected from the group consisting of: 5-[6-chloro-5-(trifluoromethyl)pyridin-3-yl]-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-3-{2-[(3S)-3-fluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-3-{2-[(3R)-3-fluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-3-{2-[(3R,4S)-3,4-difluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-{2-[(3R,4S)-3,4-difluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-{2-[(3S)-3-fluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-{2-[(3R)-3-fluoropyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(5,6-dichloropyridin-3-yl)-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[3-chloro-4-(trifluoromethyl)phenyl]-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-fluoro-3-(trifluoromethyl)phenyl]-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chloro-3-fluorophenyl)-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3-chloro-4-fluorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl 3-fluoropyrrolidine-1-carboxylate; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[(E)-(pyrrolidin-1-ylmethylidene)amino]-3H,4H-thieno[2,3-d]pyrimidin-4-one; N-{5-[4-chloro-3-(trifluoromethyl)phenyl]-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl}cyclopentanecarboxamide; 5-(4-chloro-3-fluorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl pyrrolidine-1-carboxylate; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-{3-oxo-3-[2-(trifluoromethyl)pyrrolidin-1-yl]propyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; N-[5-(3-chloro-4-fluorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]cyclopentanecarboxamide; 5-(3-chloro-4-fluorophenyl)-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; (E)-N′-{5-[4-chloro-3-(trifluoromethyl)phenyl]-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl}-N,N-dimethylmethanimidamide; 5-(3-chloro-4-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethoxy]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[3-(3-fluoropyrrolidin-1-yl)-3-oxopropyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[3-oxo-3-(pyrrolidin-1-yl)propyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; N-[5-(3-chloro-4-fluorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]pyrrolidine-1-carboxamide; 5-(3-chloro-4-fluorophenyl)-3-[1-oxo-1-(pyrrolidin-1-yl)propan-2-yl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3-chloro-4-fluorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl pyrrolidine-1-carboxylate; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethoxy]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl pyrrolidine-1-carboxylate; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-{[2-oxo-2-(pyrrolidin-1-yl)ethyl]amino}-3H,4H-thieno[2,3-d]pyrimidin-4-one; N-{5-[4-chloro-3-(trifluoromethyl)phenyl]-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl}pyrrolidine-1-carboxamide; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[1-oxo-1-(pyrrolidin-1-yl)propan-2-yl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-[3-(trifluoromethyl)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[2-fluoro-5-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(2-chloro-4-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-6-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3-chloro-4-fluorophenyl)-6-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(2-chlorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-[3-(trifluoromethoxy)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[2-methyl-4-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-6-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-(dimethylamino)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-fluoro-3-(trifluoromethyl)phenyl]-6-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[3,5-bis(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-fluoro-3-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-[2-(trifluoromethyl)pyridin-4-yl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(2,3-dichlorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[2-methoxy-5-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; ethyl 2-[5-(4-chlorophenyl)-2-methyl-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]acetate; 5-(4-chlorophenyl)-2-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-2-methyl-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[2-chloro-4-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-2-(trifluoromethyl)-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-difluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-methoxyphenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-(pyrimidin-5-yl)-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-6-methyl-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-2-(trifluoromethyl)-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(5-fluoropyridin-3-yl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[2-fluoro-4-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3,4-dichlorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(6-methoxypyridin-3-yl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-6-methyl-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[4-chloro-3-(trifluoromethyl)phenyl]-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-tert-butylphenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-[4-(trifluoromethoxy)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(1-methyl-1H-pyrazol-5-yl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 4-{4-oxo-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-5-yl}benzonitrile; 5-(3-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(3-chloro-4-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-(pyridin-4-yl)-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chloro-3-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-methylphenyl)-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-fluorophenyl)-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-5-[4-(trifluoromethyl)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(piperidin-1-yl)ethyl]-5-[4-(trifluoromethyl)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-methylphenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-fluorophenyl)-3-[2-oxo-2-(piperidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-fluorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 6-(4-chlorophenyl)-3-[2-(4,4-difluoropiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 6-(4-chlorophenyl)-3-[2-(morpholin-4-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-methylphenyl)-3-[2-oxo-2-(piperidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-5-[4-(trifluoromethyl)phenyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 2-[6-(4-chlorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]-N-cyclopropylacetamide; 6-(4-chlorophenyl)-3-[2-oxo-2-(piperidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(3-fluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 6-(4-chlorophenyl)-3-[2-oxo-2-(pyrrolidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(4-hydroxy-4-phenylpiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(4,4-difluoropiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 2-[5-(4-chlorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]-N,N-diethylacetamide; 5-(4-chlorophenyl)-3-[2-(2,6-dimethylpiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-{2-oxo-2-[2-(trifluoromethyl)pyrrolidin-1-yl]ethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-{2-[(2S)-2-methylpyrrolidin-1-yl]-2-oxoethyl}-3H,4H-thieno[2,3-d]pyrimidin-4-one; 2-[5-(4-chlorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]-N-cyclobutylacetamide; 5-(4-chlorophenyl)-3-[2-oxo-2-(piperidin-1-yl)ethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 2-[5-(4-chlorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]-N-(1-methylpyrrolidin-3-yl)acetamide; 5-(4-chlorophenyl)-3-[2-(3-hydroxypyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 2-[5-(4-chlorophenyl)-4-oxo-3H,4H-thieno[2,3-d]pyrimidin-3-yl]-N-cyclopropylacetamide; 5-(4-chlorophenyl)-3-[2-(morpholin-4-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(4-methylpiperazin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(4-fluoropiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(4-chlorophenyl)-3-[2-(4-hydroxypiperidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(5-chloro-6-fluoropyridin-3-yl)-3-[2-(3,4-difluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-(5,6-dichloropyridin-3-yl)-3-[2-(3,4-difluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; 5-[6-chloro-5-(trifluoromethyl)pyridin-3-yl]-3-[2-(3,4-difluoropyrrolidin-1-yl)-2-oxoethyl]-3H,4H-thieno[2,3-d]pyrimidin-4-one; and pharmaceutically acceptable salts thereof.

9. A method of treating a neurological disorder selected from schizophrenia, depression, an autism spectrum disorder, and Rett syndrome in a patient in need thereof, comprising administering to the patient an effective amount of a compound represented by Formula II:

and pharmaceutically acceptable salts, stereoisomers and prodrugs thereof, wherein:

L 1 is selected from the group consisting of —(CR 11 R 22 ) n —, —O—, —NR a —, —(CR 11 R 22 ) n NR a —, —(CR 11 R 22 ) n O—, and —H(C═N)—;

R 11 and R 22 are each independently selected for each occurrence from the group consisting of hydrogen and C 1-4 alkyl;

n is 1 or 2;

R 1 and R 2 , together with the nitrogen to which they are attached, form a 4-6 membered heterocyclic ring substituted on a carbon not adjacent to the nitrogen by one, two or more substituents each independently selected from the group consisting of halogen, cyano, oxo, hydroxyl and C 1-6 alkyl (optionally substituted by one, two or three halogens);

R 3 is selected from the group consisting of phenyl, naphthyl, heteroaryl, heterocyclyl and C 3-6 cycloalkyl, wherein R 3 is optionally substituted with one, two or three substituents each independently selected from C 1-4 alkyl, halogen, hydroxyl, cyano, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, C 1-6 alkylcarbonyl, R a R b N—SO 2 —, NR a R b , C(O)OH, C 1-4 alkoxycarbonyl, and NR a R b carbonyl, wherein C 1-4 alkyl, C 1-4 alkoxy, C 2-6 alkenyl, C 2-6 alkynyl, C 3-6 cycloalkyl, C 1-6 alkyl-S(O) 2 —, and C 1-6 alkylcarbonyl may be optionally substituted by one or more substituents each independently selected from halogen, hydroxyl, cyano, and NR a R b ;

R 66 and R 67 are each independently selected from the group consisting of hydrogen, halogen, C 1-4 alkyl (optionally substituted by one, two, three substituents selected from halogen, hydroxyl, cyano and NR a R b ), and phenyl (optionally substituted by one, two or three halogens); and

R a and R b are independently selected, for each occurrence, from the group consisting of: hydrogen, hydroxyl, and C 1-3 alkyl; or R a and R b , together with the nitrogen to which they are attached, form a 4-6 membered heterocyclic ring which may have an additional heteroatom selected from O, S, or N.

10. The method of claim 9 , wherein L 1 is —CH 2 —.

11. The method of claim 1 , wherein treating the neurological disorder schizophrenia comprises treating cognitive impairment associated with schizophrenia.

12. The method of claim 8 , wherein treating the neurological disorder schizophrenia comprises treating cognitive impairment associated with schizophrenia.

13. The method of claim 9 , wherein treating the neurological disorder schizophrenia comprises treating cognitive impairment associated with schizophrenia.

14. The method of claim 1 , wherein the autism spectrum disorder is Phelan-McDermid Syndrome.

15. The method of claim 8 , wherein the autism spectrum disorder is Phelan-McDermid Syndrome.

16. The method of claim 9 , wherein the autism spectrum disorder is Phelan-McDermid Syndrome.