Triazolone compound

A compound represented by formula (V) or a pharmaceutically acceptable salt thereof,

• wherein,
• ring A is selected from phenyl, pyridinyl, pyrrolyl, pyrazolyl, imidazolyl and 1,2,4-triazolyl, and the phenyl, pyridinyl, pyrrolyl, pyrazolyl and imidazolyl are optionally substituted by 1, 2 or 3 Ra;
• E1 is selected from CH2 and O;
• T1 is selected from CR4 and N;
• T2 is selected from CH and N;
• T3 is selected from CR and N;
• R1 is selected from CH2OH, COOH and CONH2;
• R2 is selected from C1-3 alkyl, and the C1-3 alkyl is optionally substituted by 1, 2 or 3 Rb;
• R3 and R4 are each independently selected from H, F, Cl, CN, CH3 and OCH3, and the CH3 and OCH3 are optionally substituted by 1, 2 or 3 Rc;
• R5 is selected from H, F, Cl and CN;
• R6 is selected from H and F;
• R7 is selected from H and
• each Ra is independently selected from F and Cl;
• each Rb is independently selected from F, Cl and Br;
• each Rc is independently selected from F, Cl and Br.