The present invention relates to a pyridonaphthyridine compound as represented by general formula (I), which has a dual PI3K and mTOR inhibition effect, and its pharmaceutically acceptable salt, stereoisomer and deuteride thereof, wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and X are as defined in the specification； the present invention also relates to a method for preparing said compound, a pharmaceutical composition and a pharmaceutical formulation containing said compound, and uses of said compound in treating and/or preventing a proliferative disease and in the manufacture of a medicament for treating and/or preventing a proliferative disease.
