Isoxazole pyrazoloindane derivatives as cognition enhancing GABA-A alpha 5 subtype ligands

A compound of formula (I):

• 15
• in which:
• one of X and Y is a nitrogen atom substituted by a group R6′ and the other is a carbon atom substituted by an isoxazole group substituted on its carbon atoms by groups R3 and R4;
• either all of W1, W2, W3 and W4 are carbon or one of W1, W2, W3 and W4 is nitrogen and the rest are carbon;
• R1 and R2 are each, independently,
• (i) hydrogen, halogen, cyano, amino, nitro, hydroxy, aminocarbonyl, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2alkynyloxy, hydroxyC1-6alkyl, C1-6alkoxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylcarbonyl, C1-6alkylaminocarbonyl or di(C1-6alkyl)aminocarbonyl, each of which is unsubstituted or substituted by one, two or three halogen atoms;
• (ii) a 5-membered heteroaromatic ring containing 1, 2, 3 or 4 heteroatoms independently selected from O, N or S, at most one of the heteroatoms being oxygen or sulphur, or a 6-membered aromatic ring optionally containing one or two nitrogen atoms, said rings being unsubstituted or substituted by at least one substituent which is halogen, hydroxy, cyano, amino, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2alkynyloxy, C1-6alkoxyC1-6alkyl, hydroxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylcarbonyl or C1-6alkylaminocarbonyl, each of which substituents is itself, where possible, unsubstituted or substituted by one, two or three halogen atoms;
• (iii) a cyclic amine ring having from 4 to 7 members, one of which is nitrogen which is the point of attachment of said ring to the rest of the molecule and optionally containing 1 additional heteroatom selected from O and N, said ring being unsubstituted or substituted by at least one substituent which is halogen, hydroxy, cyano, amino, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2alkynyloxy, C1-6alkoxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylcarbonyl or C1-6alkylaminocarbonyl, each of which substituent is itself, where possible, unsubstituted or substituted by one, two or three halogen atoms;
• R3 and R4 are independently hydrogen, halogen, hydroxy, aminocarbonyl, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2-6alkynyloxy, C1-6alkoxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylthio, hydroxyC1-6alkyl, C1-6alkylaminoC1-6alkyl, C1-6alkylcarbonyl or C1-6alkylaminocarbonyl, each of which is unsubstituted or substituted by one, two or three halogen atoms;
• or a 5-membered heteroaromatic ring containing 1, 2, 3 or 4 heteroatoms independently selected from O, N and S, at most one of the heteroatoms being oxygen or sulphur, or a 6-membered aromatic ring optionally containing 1 or 2 nitrogen atoms, the rings being unsubstituted or substituted by at least one halogen, hydroxy, aminocarbonyl, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2-6alkynyloxy, hydroxyC1-6alkyl, C1-6alkoxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylcarbonyl or C1-6alkylaminocarbonyl, each of which is unsubstituted or substituted by one, two or three halogen atoms;
• R5 is hydrogen, halogen, hydroxy, aminocarbonyl, C1-6alkyl, C2-6alkenyl, C2-6alkynyl, C1-6alkoxy, C2-6alkenyloxy, C2alkynyloxy, C1-6alkoxyC1-6alkyl, aminoC1-6alkyl, C1-6alkylcarbonyl or C1-6alkylaminocarbonyl;
• and
• one of R6 and R6′ is hydrogen;
• or a pharmaceutically acceptable salt thereof