摘要 |
The present invention relates to ethynyl derivatives of formula (I), wherein, Y is N or C-R3;and R3 is hydrogen, methyl, halogen or nitrile; R1 is phenyl or pyridinyl, which are optionally substituted by halogen, lower alkyl or lower alkoxy; R2/R2' are independently from each other hydrogen, lower alkyl or lower alkyl substituted by halogen, or R2 and R2' may form together with the N-atom to which they are attached a morpholine ring, a piperidine ring or an azetidine ring, which are unsubstituted or substituted one or more substituents selected from lower alkoxy, halogen, hydroxy or methyl; R4/R4' are independently from each other hydrogen or lower alkyl, or R4 and R4' form together a C3-5 cycloalkyl-, tetrahydrofuran- or an oxetane-ring; or to a pharmaceutically acceptable acid addition salt, to a racemic mixture, or to its corresponding enantiomer and/or optical isomer and/or stereoisomer thereof. It has now surprisingly been found that the compounds of general formula (I) are positive allosteric modulators (PAM) of the metabotropic glutamate receptor subtype 5 (mGluR5). |