Aminopyridine derivatives having Aurora A selective inhibitory action

1. A compound of Formula (I):

wherein:

n is 0 or 1;

X is O;

R l is H or C 1-2 alkyl;

R 2 is H or C 1-3 alkyl;

R 3 and R 4 are each independently H or C 1-2 alkyl, where the alkyl may be substituted with one to three of the same or different substituents selected from R 10 ;

R 5 is H or OCH 3 ; and

R 10 is F or Cl;

or a pharmaceutically acceptable salt or ester thereof

2. The compound according to claim 1 or a pharmaceutically acceptable salt or ester thereof, wherein R 1 is H or methyl.

3. The compound according to claim 2 or a pharmaceutically acceptable salt or ester thereof, wherein R 2 is H or methyl.

4. The compound according to claim 3 or a pharmaceutically acceptable salt or ester thereof, wherein R 3 and R 4 are each independently H or methyl which may be substituted with one to three of the same or different substituents selected from R 10 ; and

R 10 is F.

5. The compound according to claim 4 or a pharmaceutically acceptable salt or ester thereof, wherein the compound of Formula (I) is:

6. A compound which is:

(a) (2S)-1,1,1-trifluoropropan-2-yl (4aR,7aR)-6-[4-methyl-6-(1H-pyrazol-3-ylamino)pyrimidin-2-yl]hexahydropyrrolo[3,4-b][1,4]oxazine-4(4aH)-carboxylate; or

(b) 1,1,1-trifluoro-2-methylpropan-2-yl (4aR,7aR)-6-[4-methyl-6-(1H-pyrazol-3-ylamino)pyrimidin-2-yl]hexahydropyrrolo[3,4-b][1,4]oxazine-4(4aH)-carboxylate or a pharmaceutically acceptable salt or ester thereof.

7. A pharmaceutical composition comprising, together with pharmaceutically acceptable carrier or diluent, at least one compound according to claim 1 as active ingredient.