Patent ID: 8637557

Claim:
A compound represented by a formula (1) wherein X represents a formula —NR X1 —, a formula —C(O)NR X1 —, a formula —NR X1 C(O)NR X2 —, a formula —OC(O)NR X1 — or a formula —SO 2 NR X1 —, wherein R X1 and R X2 are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; R 1 represents an alkyl group having 1 to 6 carbon atoms, wherein the alkyl group may optionally be substituted with 1 to 5 substituents selected from the group consisting of a cycloalkyl group having 3 to 6 carbon atoms, a halogen atom, a cyano group, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, a formula —NR 11 R 12 , a formula —NR 13 COR 14 , a formula —CO 2 R 15 , a formula —CONR 16 R 17 , a formula —COR 18 , a formula —NR 19 CONR 20 R 21 , a formula —SO 2 NR 22 R 23 , a formula —SO 2 R 24 , a formula —NR 25 CO 2 R 26 , a formula —OCOR 27 and a 5- or 6-membered heterocyclic group which may optionally be substituted with an alkyl group having 1 to 6 carbon atoms, R 11 , R 12 , R 16 , R 17 , R 20 , R 21 , R 22 and R 23 are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may optionally be substituted with 1 to 3 substituents selected from a hydroxy group and an alkoxy group having 1 to 6 carbon atoms, or R 11 and R 12 , R 16 and R 17 , R 20 and R 21 , and R 22 and R 23 , together with the nitrogen atom to which they are bound, may each form a 5- or 6-membered saturated heterocyclic group (wherein the heterocyclic group may optionally be substituted with 1 to 3 substituents selected from the group consisting of a hydroxy group, an alkoxy group having 1 to 6 carbon atoms and an alkoxycarbonyl group having 2 to 7 carbon atoms), and R 13 , R 14 , R 15 , R 18 , R 19 , R 24 , R 25 , R 26 and R 27 are each independently a hydrogen atom, or an alkyl group having 1 to 6 carbon atoms which may optionally be substituted with 1 to 3 substituents selected from a hydroxy group and an alkoxy group having 1 to 6 carbon atoms; R 2 represents an alkyl group having 1 to 6 carbon atoms which may optionally be substituted with 1 to 3 halogen atoms; Y represents a single bond; and R 3 represents a pyridyl group or a pharmaceutically acceptable salt thereof, with the proviso that when X is a formula —NH—, N,4-dimethyl-5-[3-(pyridin-3-ylmethyl)-1,2,4-oxadiazol-5-yl]-1,3-thiazol-2-amine and N-ethyl-4-methyl-5-[3-(pyridin-2-yl)-1,2,4-oxadiazol-5-yl]-1,3-thiazol-2-amine are excluded.