| abstract |
Disclosed is a compound represented by the general formula [I] below or a pharmaceutically acceptable salt or ester thereof. [I] [In the formula, the ring A represents a five-membered aromatic heterocyclic group containing at least one heteroatom selected from a nitrogen atom or the like; A1 and A2 represent nitrogen atoms or the like; all of X2, X3, X4 and X5 represent carbon atoms, or one of X2, X3, X4 and X5 represents a nitrogen atom and the rest represent carbon atoms; R1 represents a hydrogen atom or the like; R2, R3, R4 and R5 represent hydrogen atoms or the like; R6 and R6' represent hydrogen atoms or the like; R7 represents an aryl group or the like; and R8 represents an amino group or a hydroxy group. |