| abstract |
The present invention relates to compounds of the general formula wherein R1 is -(CH2)n-aryl or -(CH2)n-heteroaryl, wherein such groups are unsubstituted or substituted by one or more substituents, selected from the group consisting of halogen, lower alkyl substituted by halogen, lower alkoxy, lower alkyl, cyano, nitro, -O-lower alkyl substituted by halogen or morpholinyl; R2 is -(CH2)n-aryl or -(CH2)n-heteroaryl, wherein such groups are unsubstituted or substituted by one or more substituents, selected from the group consisting of lower alkyl, lower alkoxy, halogen or -N(lower alkyl)2; R3 is hydrogen or lower alkyl; R4 is -(CH2)n-aryl or -(CH2)n-heteroaryl, wherein such groups are unsubstituted or substituted by one or more substituents, selected from the group consisting of halogen or lower alkoxy, or is lower alkyl, -(CH2)n-cycloalkyl; or R3 and R4 form together with the N-atom a heterocyclic ring; n is 0, 1 or 2; and to pharmaceutically acceptable acid addition salts thereof. It has been found that the compounds of general formula I or their tautomeric forms are good inhibitors of the glycine transporter 1 (GIyT-1), and that they have a good selectivity to glycine transporter 2 (GIyT-2) inhibitors, useful for the treatment of schizophrenia. |