| abstract |
Disclosed are benzomorpholine derivatives as represented by the following formula (I) and pharmaceutical compositions comprising the derivatives as well as methods of preparation thereof, R 1 , R 2 and R 3 are as defined in the specification. The benzomorpholine derivatives of formula (I) are an inhibitor of phosphatidylinositol 3-kinases (PI3K), and have a good inhibitory effect on PI3K and on cancer cell proliferation, thereby serving as a therapeutic agent for the treatment of tumors. |