申请人:HOFFMANN LA ROCHE
公开号:WO2009071464A1
公开(公告)日:2009-06-11
The present invention is concerned with isoxazolo-pyrazine derivatives of formula (I) wherein X is O or NH; R1 is phenyl or pyridine-2-yl, wherein the rings may be optionally substituted with one, two or three halo; R2 is H or C1-4alkyl; R3 and R4 each are independently H, optionally substituted C1-7alkyl, optionally substituted C1-7alko.xy, CN, halo, NO2, -C(0)-Ra -C(0)-NRbRc or R3 and R4 together form an optionally substituted annelated benzo ring, or a pharmaceutically acceptable salt thereof, having affinity and selectivity for GABA A α5 receptor binding site, their manufacture, pharmaceutical compositions containing them and their use as medicaments. The active compounds of the present invention are useful as cognitive enhancer or for the treatment of cognitive disorders like Alzheimer's disease.