PHOSPHORUS-CONTAINING PYRIDO[2,3-D]PYRIMIDIN-7-ONES OR THEIR PHARMACEUTICALLY ACCEPTABLE SALTS, PHARMACEUTICAL COMPOSITIONS CONTAINING THIS COMPOUND AND USE THEREOF
The invention provides a phosphorus-containing pyridine[2,3-d]pyrimidine-7-ketone compound as shown in the formula (I) or its pharmaceutically acceptable salt, and also discloses a preparation method of the compound, a pharmaceutical composition containing the phosphorus-containing pyridine[2,3-d]pyrimidine-7-ketone compound and an application thereof. The compound is a protein kinase (such as PI3K) inhibitor and can be used in treating diseases caused by abnormal protein kinase activities, such as tumour, etc.