CHLORINATED TETRALIN COMPOUNDS AND PHARMACEUTICAL COMPOSITIONS

1 . A compound of Formula I:

or a pharmaceutically acceptable salt thereof, wherein R 1 , R 2 , R 3 and R 4 are independently hydrogen or halogen, and at least one of R 1 , R 2 , R 3 and R 4 is chloro.

2 . The compound of claim 1 , wherein the compound of Formula I is selected from the group consisting of:

(S)-2-(((S)-7-chloro-6-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide;

(S)-2-(((S)-6-chloro-8-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide; and

(S)-2-(((S)-8-chloro-6-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide.

3 . A pharmaceutical composition comprising a compound of Formula I:

or a pharmaceutically acceptable salt thereof, wherein R 1 , R 2 , R 3 and R 4 are independently hydrogen or halogen, and at least one of R 1 , R 2 , R 3 and R 4 is chloro.

4 . A pharmaceutical composition according to claim 3 comprising a compound selected from the group consisting of:

(S)-2-(((S)-7-chloro-6-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide;

(S)-2-(((S)-6-chloro-8-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide; and

(S)-2-(((S)-8-chloro-6-fluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino)propan-2-yl)-1H-imidazol-4-yl)pentanamide dihydrobromide.

5 . A pharmaceutical composition comprising a compound of Formula IA which is

or a pharmaceutically acceptable salt thereof.

6 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 1 μg to about 500 μg.

7 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 5 μg to about 500 μg.

8 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 10 μg to about 250 μg.

9 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 10 μg to about 100 μg.

10 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 10 μg to about 50 μg.

11 . The pharmaceutical composition according to claim 5 , wherein the compound of Formula IA is present in an amount of about 12.5 μg to about 50 μg.

12 . The pharmaceutical composition according to claim 5 , further comprising a gamma-secretase inhibitor selected from the group consisting of nirogacestat, or a pharmaceutically acceptable salt thereof, crenigacestat, or a pharmaceutically acceptable salt thereof, AL101, or a pharmaceutically acceptable salt thereof, AL102, or a pharmaceutically acceptable salt thereof, semagacestat, or a pharmaceutically acceptable salt thereof, avagacestat, or a pharmaceutically acceptable salt thereof, and ianabecestat, or a pharmaceutically acceptable salt thereof.

13 . The pharmaceutical composition according to claim 5 , further comprising nirogacestat, or a pharmaceutically acceptable salt thereof.

14 . The pharmaceutical composition according to claim 5 , further comprising a pharmaceutically acceptable carrier.

15 . The pharmaceutical composition according to claim 5 , wherein the pharmaceutical composition is for oral administration.

16 . The pharmaceutical composition according to claim 5 , wherein the pharmaceutical composition is a tablet.