The disclosure relates to pyridine derivative compounds of formula (I) wherein W, X, R15, R16, R17, R18 and R19 are as defined in the specification, these compounds are modulators of metabotropic glutamate receptors - subtype 5 ('mGluR5') which are useful for the treatment of central nervous system disorders as well as other disorders modulated by mGluR5 receptors. These compounds are particularly suitable for treating or preventing central nervous system disorders selected from the group consisting of: addiction, tolerance or dependence, affective disorders, psychiatric disease, Parkinson's disease, memory impairment, Alzheimer's disease, dementia, delirium tremens, other forms of neurodegeneration, neurotoxicity, and ischemia; for treating or preventing inflammatory or neuropathic pain; for treating or preventing behaviour disorders and dependence disorders selected from the group consisting of alcohol, nicotine, cocaine, amphetamine, benzodiazepine, analgesics, opiate or other substance tolerance or dependence, bulimia nervosa, anorexia nervosa, gambling dependence, sex dependence, or obsessive compulsive disorders; for treating or preventing schizophrenia, depression and attention-deficit/hyperactivity disorder; and such other disorders modulated by mGluR5 receptors.
Alkynyl derivatives as modulators of metabotropic glutamate receptors