Heterocyclic compound

A compound of the formula (I) or a salt thereof:

• wherein
• A2 and A3 are N and A1 is CH, or A1 and A3 are N and A2 is CH,
• B's are CH and n is 0,
• R1 is -L1-L2-Y, wherein -L1-L2-is —NH— or —O—,
• R2 is halogen, —OH, —O-lower alkyl, —CN, or lower alkyl which may be substituted with one or more substituents selected from the group consisting of halogen, —OH, —O— lower alkyl, and —CN,
• Y is a non-aromatic heterocycle which may be substituted with one or more substituents selected from the Group D1, and
• the Group D1 consists of:
• -L5a-non-aromatic heterocycle which may be substituted with one or more substituents selected from the group consisting of lower alkyl, —C(O)O-lower alkyl, —C(O)-lower alkyl, and oxo, wherein L5a represents a bond or —C(O)—.