Isochroman compound

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

• wherein T is N or CH;
• R1 and R2 are each independently H, F, Cl, Br, I, or C1-3 alkyl, wherein the C1-3 alkyl is optionally substituted by 1, 2, or 3 Ra;
• each Ra is independently F, Cl, Br, I, —CN, —OH or —NH2;
• R3 and R4 are each independently H, F, Cl, Br, I, CN, C1-3 alkyl, C1-3 alkoxy,
• wherein the C1-3 alkyl is optionally substituted by 1, 2 or 3 Re;
• Rb and Rc are each independently H, —CH3, —CH2CH3, —(CH2)2CH3 or —CH(CH3)2;
• Rd is —CH3, —CH2CH3, —(CH2)2CH3 or —CH(CH3)2;
• each Re is independently F, Cl, Br, I, —CN, —OH or —NH2.