The present invention relates to ethynyl derivatives of formula I wherein Y is N or CH R1 is fluoro or chloro or to a pharmaceutically acceptable acid addition salt thereof. The compounds of general formula I are metabotropic glutamate receptor antagonists (negative allosteric modulators) for use in the treatment of anxiety and pain, depression, Fragile-X syndrome, autism spectrum disorders, Parkinson’s disease, and gastroesophageal reflux disease (GERD).
Ethynyl derivatives