The present invention relates to pyridopyrimidine derivatives, a preparation method thereof and medical use thereof. Specifically, the present invention relates to a pyridopyrimidine derivative represented by the general formula (I), a preparation method thereof, a pharmaceutical composition containing the same and the use thereof as a therapeutic agent, particularly as a TLR8 agonist. The definition of each groups of formula (I) is as defined in the specification.本發明涉及吡啶并嘧啶類衍生物、其製備方法及其在醫藥上的應用。具體而言，本發明涉及一種通式(I)所示的吡啶并嘧啶類衍生物、其製備方法及含有該衍生物的醫藥組成物以及其作為治療劑，特別是作為TLR8激動劑的用途，其中通式(I)的各取代基與說明書中的定義相同。
