1,4-disubstituted 3-cyano-pyridone derivatives and their use as positive allosteric modulators of mGluR2-receptors

A method for treating a central nervous system disorder in a human, wherein the central nervous system disorder is an anxiety disorder selected from the group consisting of agoraphobia, generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD), panic disorder, posttraumatic stress disorder (PTSD), social phobia and other phobias, or a psychotic disorder selected from the group consisting of schizophrenia, schizoaffective disorder and schizophreniform disorder, the method comprising administering to the human an effective amount of a compound of formula

• including any stereochemically isomeric form thereof, wherein
• R1 is C4-6alkyl, or C1-3alkyl substituted with C3-7cycloalkyl;
• R2 is hydrogen or halo;
• A is pyridinyl substituted with one or two substituents, each substituent independently selected from halo or C1-4alkyl;
• n is an integer of value 1 or 2;
• or a pharmaceutically acceptable salt thereof;
• provided that if R2 is 2-fluoro then A is not 3-pyridinyl substituted with one or two substituents, each substituent independently selected from halo or C1-4alkyl;
• and
• provided that the compound is other than
• —R1
• R2
• —A
• H
• H
• H
• H