Gamma-secretase inhibitors

1. A compound according to formula I:

wherein

n is 1 or 2;

X represents CN, N 3 , OH, CO 2 H, CO 2 R 1 , CON(R 2 ) 2 , SO 2 R 1 , SO 2 N(R 2 ) 2 or OSO 2 N(R 2 ) 2 ;

R 1 represents CF 3 , C 1-6 alkyl, C 2-6 alkenyl, C 3-9 cycloalkyl or C 3-6 cycloalkylC 1-6 alkyl, any of which optionally bear up to 2 substituents selected from halogen, CN, CF 3 , OR 3 , aryloxy, COR 3 , CO 2 R 3 , OCOR 4 , SO 2 R 4 , N(R 5 ) 2 , and CON(R 5 ) 2 ,

or R 1 represents aryl or arylC 1-6 alkyl;

each R 2 independently represents H or C 1-6 alkyl, C 2-6 alkenyl, C 3-9 cycloalkyl or C 3-6 cycloalkylC 1-6 alkyl, any of which optionally bear up to 2 substituents selected from halogen, CN, CF 3 , OR 3 , COR 3 , CO 2 R 3 , OCOR 4 , SO 2 R 4 and CON(R 5 ) 2 ;

R 3 represents H or C 1-4 alkyl;

R 4 represents C 1-4 alkyl;

R 5 represents H or C 1-4 alkyl;

the two R 6 groups and the nitrogen to which they are attached complete an N-heterocyclyl group that is six-membered which is attached through N, wherein the one nitrogen is the only heteroatom, or

the two R 6 groups and the nitrogen to which they are attached complete an N-heterocyclyl group that is five-membered which is attached through N or a heteroaryl group that is five-membered consisting of carbon and nitrogen atoms which is attached through N;

Ar 2 represents phenyl which bears 0-3 substituents independently selected from halogen, CN, NO 2 , CF 3 , CHF 2 , OH, OCF 3 , CHO, CH═NOH, C 1-4 alkoxy, C 1-4 alkoxycarbonyl, C 2-6 acyl, C 2-6 alkenyl and C 1-4 alkyl which optionally bears a substituent selected from halogen, CN, NO 2 , CF 3 , OH and C 1-4 alkoxy;

“aryl” at every occurrence thereof refers to phenyl or heteroaryl which optionally bear up to 3 substituents selected from halogen, CN, NO 2 , CF 3 , OCF 3 , OH, COR 3 , CO 2 R 3 , OCOR 4 , N(R 5 ) 2 , CON(R 5 ) 2 and optionally-substituted C 1-6 alkyl, C 1-6 alkoxy, C 2-6 alkenyl or C 2-6 alkenyloxy wherein the substituent on the optionally-substituted C 1-6 alkyl, C 1-6 alkoxy, C 2-6 alkenyl or C 2-6 alkenyloxy is selected from halogen, CN, CF 3 , phenyl, OR 3 , CO 2 R 3 , OCOR 3a , N(R 5 ) 2 and CON(R 5 ) 2 ; and

“N-heterocyclyl” at every occurrence thereof refers to a heterocyclic ring system, said ring system being non-aromatic and consisting of the indicated number of atoms, and optionally bearing up to 3 substituents selected from oxo, halogen, CN, NO 2 , CF 3 , OCF 3 , OR 3 , COR 3 , CO 2 R 3 , OCOR 4 , OSO 2 R 4 , N(R 5 ) 2 , CON(R 5 ) 2 and optionally-substituted phenyl, C 1-6 alkyl, C 1-6 alkoxy, C 2-6 alkenyl or 6alkenyloxy wherein the substituent on the optionally-substituted phenyl, C 1-6 alkyl, C 1-6 alkoxy, C 2-6 alkenyl or C 2-6 alkenyloxy is selected from halogen, CN, CF 3 , OR 3 , CO 2 R 3 , OCOR 4 , N(R 5 ) 2 and CON(R 5 ) 2 ;

or a pharmaceutically acceptable salt thereof.

2. A compound according to claim 1 wherein X represents CO 2 H, CO 2 R 1 , CON(R 2 ) 2 , SO 2 R 1 or SO 2 N(R 2 ) 2 .