Alkynly-substituted spirocyclic sulfamides for the treatment of alzheimer's disease

1. A compound of formula I:

wherein X represents Ar, L-N(R 1 ) 2 , L-CON(R 1 ) 2 , L-CO 2 R 1 or L-CN;

L represents a hydrocarbon chain of 1–7 carbon atoms which, when the chain consists of 2 or more carbon atoms, is optionally interrupted by an oxygen atom;

R 1 represents H or R 2 ; or two R 1 groups attached to a single nitrogen atom may complete a heterocyclic ring of 3–7 members bearing 0–3 substituents selected from halogen, oxo, NO 2 , CN, CF 3 , R 2 , C 2-6 acyl, C 2-6 alkenyl, OH, OR 2 , CO 2 H, CO 2 R 2 , Ar, ArCH 2 O, and ArO;

R 2 represents C 1-6 alkyl which is optionally substituted with halogen, Ar, NO 2 , CN, CF 3 , OH or C 1-4 alkoxy;

R 14 represents H or C 1-6 alkyl, C 3-7 cycloalkyl, C 3-6 cycloalkylC 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, phenyl or benzyl, any of which optionally bear up to 3 halogen substituents or one substituent selected from CN, NO 2 , OH, C 1-4 alkoxy, CO 2 H, C 1-4 alkoxycarbonyl, C 2-6 acyl, C 2-6 acyloxy, amino, C 1-4 alkylamino, di(C 1-4 alkyl)amino, C 2-6 acylamino, carbamoyl, C 1-4 alkylcarbamoyl and di(C 1-4 alkyl)carbamoyl; and

Ar represents phenyl or heteroaryl either of which optionally bears up to 3 substituents independently selected from halogen, CF 3 , NO 2 , CN, OCF 3 , C 1-6 alkyl and C 1-6 alkoxy;

or a pharmaceutically acceptable salt thereof.

2. A compound according to claim 1 wherein X represents Ar and Ar represents optionally-substituted phenyl, pyridyl, pyrimidinyl or pyrazinyl.

3. A compound according to claim 1 wherein L is selected from —CH 2 —, —(CH 2 ) 4 —, —(CH 2 ) 5 —, —(CH 2 ) 2 —O—(CH 2 ) 2 — and —(CH 2 ) 2 —O—CH 2 —.

4. A compound according to claim 1 of formula II:

or a pharmaceutically acceptable salt thereof.

5. A compound according to claim 4 wherein X is selected from 6-membered heteroaryl, —CH 2 N(R 1 ) 2 , —(CH 2 ) 5 N(R 1 ) 2 —(CH 2 ) 4 CON(R 1 ) 2 , —(CH 2 )CO 2 R 2 , —(CH 2 ) 2 —O—CH 2 CN and —(CH 2 ) 2 —O—(CH 2 ) 2 N(R 1 ) 2 .

6. A compound according to claim 5 wherein X is selected from 2-pyridyl, 3-pyridyl, pyrazinyl, 4-trifluoropiperidin-1-ylmethyl, —(CH 2 ) 5 NH—CH 2 Ph, —(CH 2 ) 4 CONHCH 2 Ph, —(CH 2 ) 4 CO 2 H, —(CH 2 ) 2 —O—CH 2 CN and —(CH 2 ) 2 —O—(CH 2 ) 2 NH 2 .

7. A pharmaceutical composition comprising a compound according to any previous claim and a pharmaceutically acceptable carrier.

8. A method of treatment of a subject suffering from Alzheimer's disease which comprises administering to that person an effective amount of a compound according to any of claims 1 – 6 .