Compounds having both effects of bet bromodomain protein inhibition and pd-l1 gene regulation

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

• wherein,
• R1, R2 and R3 are each independently selected from C1-3 alkyl optionally substituted with 1, 2 or 3 Ra;
• R4 is selected from the group consisting of H, F, Cl, Br, I, OH, and NH2;
• R5 is selected from the group consisting of H, OH, NH2, CN, C1-6 alkyl, C1-6 alkylamino, C1-6 alkoxy and 4- to 6-membered heterocycloalkyl, wherein the C1-6 alkyl, C1-6 alkylamino, C1-6 alkoxy and 4- to 6-membered heterocycloalkyl are each independently optionally substituted with 1, 2 or 3 Rb;
• Z is selected from the group consisting of O, NR6 and CHR6;
• R6 is selected from the group consisting of H and C1-3 alkyl optionally substituted with 1, 2 or 3 Rc;
• or R5, R6 and the atoms to which they are attached together form 5- to 6-membered heterocycloalkenyl or 5- to 6-membered heteroaryl, wherein the 5- to 6-membered hetercyclooalkenyl and 5- to 6-membered heteroaryl are each independently optionally substituted with 1, 2 or 3 Rd;
• Ra, Rc, and Rd are each independently selected from the group consisting of F, Cl, Br, I, OH, NH2, and CH3;
• Rb is selected from the group consisting of F, Cl, Br, I, OH, NH2, CN, C1-3 alkyl and C1-3 alkoxy, wherein the C1-3 alkyl and C1-3 alkoxy are each independently optionally substituted with 1, 2 or 3 R;
• R is each independently selected from the group consisting of F, Cl, Br, I, OH, NH2 and CH3;
• the 4- to 6-membered heterocycloalkyl, 5- to 6-membered heterocycloalkenyl and 5- to 6-membered heteroaryl each contain 1, 2, 3 or 4 heteroatoms or heteroatom groups independently selected from the group consisting of —NH—, —O—, —S— and N.