Isoxazole-pyridine derivatives as modulators of GABA

A compound of formula I ** ** in Formula X is O or NH; R1 is a) C1-7 alkyl or C1-7 alkoxy, each optionally substituted with 1, 2, 3 or 4 substituents seleccionadosindependientemente the group consisting of halogen, cyano, hydroxy and C1-7 alkoxy, b) cycloalkyl C3- 7 oheterociclilo, each optionally substituted with 1, 2, 3 or 4 substituents independently selected theGroup consisting of halogen, cyano, hydroxy, C1-7 alkyl and C1-7 alkoxy; R2 is hydrogen or C1-7 which may optionally be substituted with 1, 2, 3 or 4 substituents seleccionadosindependientemente the group consisting of halogen, cyano and C1-7 alkyl; R3 is hydrogen or C1-7 which may optionally be substituted with 1, 2, 3 or 4 substituents seleccionadosindependientemente the group consisting of halogen, cyano, hydroxy and C1-7 alkyl; R4 is C1-7 alkyl, C3-7 cycloalkyl, heterocyclyl or heteroaryl, each optionally substituted with 1, 2, 3 or 4sustituyentes independently selected from the group consisting of halogen, cyano, hydroxy, oxo, alkoxy C1 C1-7y -7, or R3 and R4, together with the nitrogen atom to which they are attached, form heterocyclyl optionally substituted with 1, 2, 3 or 4 substituents independently selected from the group consisting dehalogeno, cyano, hydroxy, alkyl C1-7, C1-7 alkoxy and oxo; and pharmaceutically acceptable salts thereof. wherein "heterocyclyl" refers to a saturated monocyclic monovalent 3 to 7 membered or parcialmenteinsaturado containing one, two or three heteroatoms in the ring selected from N, oo S, and wherein "heteroaryl" refers to a monocyclic aromatic ring of 5 to 6 members or a bicyclic ring of 9 to 10miembros which can comprise 1, 2 or 3 atoms selected from nitrogen, oxygen and / or sulfur.