| abstract |
The present invention provides a novel tricyclic aromatic heterocyclic compound, a preparation method therefor, a pharmaceutical composition and an application thereof. Specifically, the present invention provides a compound as represented by the following formula I, or optical isomers, hydrates, and solvates thereof, or pharmaceutically-acceptable salts thereof. Definitions of groups are as stated in the description. The compound as represented by formula I can be used for treating diseases related to a PD-1/PD-L 1 signal pathway. |