Dual binding site acetylcholinesterase inhibitors for the treatment of alzheimer's disease

A compound represented by the general formula (I)

• wherein:
• X is the following radical:
• L is independently selected from —C(R)(R″)—, —CO—, —O— or —NR′—
• n is zero, one, two, three, four, five, six, seven, eight, nine or ten
• R and R″ are independently selected from hydrogen, alkyl, aryl, heteroaryl, halo, haloalkyl, alkoxy, hydroxyl, nitro and alkylthio
• D is independently selected from —C(R9)—, ═C—, or —N—
• A1, A2, A3, A4, A5, A7, A8, E and G are independently selected from —CO—, —C(R10)(R11)—, ═C(R10)—, —N(R12)—, ═N—, —O—, 13 S(O)t—
• R1, R2, R3, R4, R9, R10 and R11 are independently selected from hydrogen, alkyl, alkoxy, hydroxyl, alkylthio, cycloalkyl, haloalkyl, halo, aryl, -(Z)n-aryl, heteroaryl, —O(R7), —C(O)R7, —C(O)OR7, —S(O)t, cyano, nitro and mercapto, aryl substituted by alkyl, alkoxy, hydroxy, halo, haloalkyl, nitro or alkylthio;
• and heteroaryl substituted by alkyl, alkoxy, hydroxy, halo, haloalkyl, nitro or alkylthio
• Z is independently selected from —C(R7)(R8)—, —C(O)—, —O—, —C(═NR7)—, —S(O)t, N(R7)—
• R7 and R8 are independently selected from hydrogen, alkyl, alkoxy, alkylthio, cycloalkyl, haloalkyl, halo, aryl, heteroaryl, cyano, nitro, mercapto, aryl substituted by alkyl, alkoxy, hydroxy, halo, haloalkyl, nitro or alkylthio;
• and heteroaryl substituted by alkyl, alkoxy, hydroxy, halo, haloalkyl, nitro or alkylthio
• t is zero, one or two;
• with the exclusion of the following two compounds: