Anti-tumor agent for undifferentiated gastric cancer

Compounds represented by the following formula (I), or salts thereof pharmacologically acceptable or solvate thereof may be against undifferentiated gastric cancer, exhibit more effectively the effect. Further, the compound represented by the following formula (I), or a pharmaceutically acceptable salt or solvate thereof, is expressed cells and mutant FGFR2 overexpressing FGFR2 the living body comprising at least one selected from the group consisting of cells, can be exhibited more effectively effect. The general formula (I)